Stall Converter: Tech Question ..
Lord-Data
understanding that its effectivly a device that goes in an auto that is
effectivly similar to dropping the clutch in a manual? Basically, i'm told
it will let the engine rev up to a certain rpm, before engaging to the
wheels. If this is roughly correct, wouldnt this be pretty detrimental to
the transmission and other parts of the car? An auto's transmission woudlnt
really have been built for dropping it at high revs all the time, would it?
Also, is the device switchable? So you use it only sometimes? or would it do
it every time you took off?
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: Michael Saunders (aka, Lord-Data)
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Brenden
I have a 3500rpm histall in my car.
They just don't hit hard like dumping a clutch. My car will drive off even @
900rpm. Though it has a 3500rpm histall. The histall works like riding a
clutch. It create's a friction inefficiency. This inefficiency will make the
car move forward but not as rapidly. As when the convertor is locked up @
3500 the car will accellerate much faster than when the auto is slipping @
any rpm below 3500.
The more the histall slips the hotter the auto gets. auto gets too hot then
the auto blows up. With a histall you have to make sure your diff ratio is
suited to the application. My diff ratio is 4.11:1. This was the convertor
is locked up @ 3500 in 1st @ 60k's / @3500 @ 80k's and @ 3500 @ 100k's.
Brenden
"Lord-Data" <da...@ihug.com.au> wrote in message
news:a9daj8$ccg$1...@lust.ihug.co.nz...
Noddy
in
> understanding that its effectivly a device that goes in an auto that is
> effectivly similar to dropping the clutch in a manual? Basically, i'm told
> it will let the engine rev up to a certain rpm, before engaging to the
> wheels. If this is roughly correct, wouldnt this be pretty detrimental to
> the transmission and other parts of the car? An auto's transmission
woudlnt
> really have been built for dropping it at high revs all the time, would
it?
> Also, is the device switchable? So you use it only sometimes? or would it
do
> it every time you took off?
That's kind of the way it works, but it's a permanent fixture that's not
selectable. There is no such thing as a "stall converter", the correct term
is Torque Converter.
A torque converter is a fluid coupling between the engine and automatic
transmission, and it works a little bit like a regular clutch. It also
drives the oil pump in most automatic transmissions to provide hydraulic
pressure. Torque converters basically comprise of three fans inside the
converter body. One fan, the impellor, is fixed to the converter housing and
spins with the crankshaft when the engine is running, and it's similar in
function to a manual car's pressure plate. Another, the turbine, connects to
the splined input shaft of the auto and is kind of like a regular clutch
plate in operation. The third fan, the stator, is a smaller one that lives
in between the impellor and turbine, and it's job is to help direct oil flow
when the impellor and turbine are spinning at different speeds. The
converter body itself is a round dohnut shaped device consisting of two
half's of steel welded together, and it's full of fluid while in operation
In operation, a converter is a pretty simple device. When it turns with the
engine, the fixed impellor creates a centrifugal force on the fluid inside
it, and the spinning fluid is thrown against the blades of the turbine
which, in turn, causes the turbine to spin and drive the input shaft. When
the engine speed is low, like at idle for example, not enough force is
generated by the impellor to turn the turbine at great speed and the car can
sit motionless while in gear. However, once the rpm is increased, more force
is generated by the impellor and the turbine begins to spin. When it does,
there is a speed difference between the two known as "slip", and the stator
helps to improve the situation by directing the fluid against the turbine as
effectively as possible until both the impellor and turbine are spinning at
close to the same speed.
Conventional torque converters always have slip and most turn the turbine at
nine tenths of impellor speed, which is why most older automatically
equipped cars were always a little thirstier than their manual counterparts.
However, modern lock up converters are a different story as the impellor and
turbine are mechanically locked to each other once the car is cruising in
top gear, and they become as efficient as a regular manual.
The stall speed of a torque converter is often a point of confusion to many,
but it's a pretty simple concept. It basically refers to the maximum speed
an impellor can spin without rotating the turbine. Most factory converters
have a stall speed of around 1800 rpm or so, and this figure is the point
where torque multiplication is at it's greatest. The torque multiplication
effect of a converter is much the same as releasing the clutch pedal on a
manual at a certain rpm. If you rev the engine moderately and release the
clutch, you'll most likely drive away smoothly at a moderate pace. However,
rev the engine hard and release the clutch and you'll get quicker
acceleration as the engine is higher up in it's torque range when the clutch
is released.
The stall speed of a converter works in the same way. The higher rpm reached
before the turbine is allowed to spin creates more torque on the input
shaft, and can make an automatic transmission equipped car accelerate quite
quickly as the engine isn't "bogged down" under it's power spread when the
car starts to move. Raising the stall speed of a converter is usually
achieved by changing the angle of the blades on the turbine so they don't
"catch" as much fluid at lower rpm.
High stall speed converters can be very successful in certain applications,
but generally they're a complete waste of time on a street driven car, as
they're very impractical and have lots of disadvantages for street use. A
car so equipped can still be driven at low speeds, but having a converter
with a stall speed of 3500 rpm will mean that at rpm's below this the amount
of slip is high, and the heat generated in the converter is extreme. It's
kind of like driving a manual while riding the clutch causing it to slip.
You'll get the car to move at slower speeds with moderate acceleration, but
with an increased rpm that would otherwise be normal and wasting lots of
fuel in the process.
Years ago when I was actively involved in drag racing, I used to run an 8
inch converter with a stall speed of close to 7000rpm behind a pretty high
revving small block Chev, and that worked extremely well in conjunction with
a pneumatic trans brake. However, it was piss poor at moving the car around
at low speeds, with something like 3000 rpm being required to go a bit
faster than walking pace and the heat generated in the converter was
sensational.
Regards,
Noddy.
Lord-Data
I love finding out how things work too :)
answers my bottom line question pefectly too, do i want one :) and the
answer was no :)
Thanks again :)
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: Michael Saunders (aka, Lord-Data)
: ICQ: 514055
: MSN: gd...@msn.com
: URL: http://www.thewolfsarcade.com
: EBay: http://www.ebayshops.com.au/id=30953730
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"Noddy" <das...@optushome.com.au> wrote in message
news:a9dnk0$29vau$1...@ID-132740.news.dfncis.de...
d
a great site imho. thats where i learnt how a turbo engine works :)
d.
"Lord-Data" <da...@ihug.com.au> wrote in message
news:a9dopj$lj8$1...@lust.ihug.co.nz...
atec77(nospam)
should be under 1k and will handle a big block up to 650 +horse , you
will have to change the bell housing but its not to hard.. comment was
piss the stallie off and go for a 2k , he does know this stuff.. maybe
you will consider ?
Brenden
My cam has 610thou lift and doesn't come in till 3800. Recommended stall for
my cam is 4400rpm.
Were you aware the stock covertors are 1800rpm stall?
I'll be look @ a manual for mine @ just under $1000 a pop for an auto it's
killing me. I've popped 3 stage III auto's. 2 built at one place and another
build at a total different place.
My cars going back to the place that built my engine/auto/diff on Wed. He
reckons the governor has crap in it. If he fixes it? I am going to sell the
5000k old auto and histall. Then put a 5spd manual in.
I agree they'll take 650hp but for how long? I reckon I could pop one of
your mates autos in under 5000k's. I seemed to have popped everyone elses.
Transtyle here in Vic built 3 stage II autos for my old 253 HZ. Popped 3
went back for warranty. Got another new one and took it straight over the
road and swapped for a reco M21 manual conversion. Drove around for 3 years
without a problem.
Brenden
"atec77(nospam)" <"atec77(nospam)"@(remove)hotmail.com> wrote in message
news:3cbab984$0$11454$afc3...@news.optusnet.com.au...
DAN
news:1vKu8.12734$o66....@news-server.bigpond.net.au...
> 2000rpm stall in my auto won't allow my engine to idle. Let alone drive
off.
> My cam has 610thou lift and doesn't come in till 3800. Recommended stall
for
> my cam is 4400rpm.
>
> Were you aware the stock covertors are 1800rpm stall?
>
> I'll be look @ a manual for mine @ just under $1000 a pop for an auto it's
> killing me. I've popped 3 stage III auto's. 2 built at one place and
another
> build at a total different place.
>
> My cars going back to the place that built my engine/auto/diff on Wed. He
> reckons the governor has crap in it. If he fixes it? I am going to sell
the
> 5000k old auto and histall. Then put a 5spd manual in.
>
> I agree they'll take 650hp but for how long? I reckon I could pop one of
> your mates autos in under 5000k's. I seemed to have popped everyone elses.
>
> Transtyle here in Vic built 3 stage II autos for my old 253 HZ. Popped 3
> went back for warranty. Got another new one and took it straight over the
> road and swapped for a reco M21 manual conversion. Drove around for 3
years
> without a problem.
I've got an idea... how about you revise your driving style fuck nuckle!! A
beefed up auto with a good histall will hold shit loads more power than an
M21. What kinda ponies you putting out?
DAN
atec77(nospam)
pontiac locker ?. I don't know enough about it however I can relay the
info and he's yelling me the C10 will handle any clevo , he's running a
big block with lots more grunt than yours and a I have to suggest its a
matter of cooling and set-up.. its worth recurving the dizzy and tuning
for a degree of smoothness even if you lose 10 horse for the ability to
drive it , but if you install a good manual that will do it.
Now what are you going to use ?. the T5 and top loader wont handle the
power ?.
Brenden
Get a grip. Plenty of people running M21 behind high hp engines. I watch
them @ Spring Nats and the Easter Nat's every year.
My point with the HZ is Transtyle can't build a good Trimatic auto. All
three shuddered in reverse 10k's old Trimatic autos. Nothing more nothing
less.
As for my driving style. I built the car for street/strip. The current auto
did about 4950k's then 50k's on the dyno. Pretty much after the dyno run it
was stuffed. Whats a dyno run got to do with my driving style?
XB has 240rwhp running stock exhaust but has extractors.
As for the 253 is wasn't anything over 250max @ the fly. Nothing special
about it.
My current situation is 240rwhp/4.11 gears/C4 with 3500histall thats 5
months old max. Not one auto seems to do the job for longer than 5000k's.
Whats pissing me off is paying cash for idiots to built autos that don't
last. $3000 so far. I'd like to keep and auto but my finances can't afford
to keep paying for them.
If you've got any more constructive coments? Feel free this newsgroup is
public.
Brenden
"DAN" <ydou...@yahoo.com> wrote in message
news:GbLu8.31$Mh6....@nsw.nnrp.telstra.net...
Brenden
All my C10/4/9's don't last. Why? I am buggered. If I could find someone?
Who won't bullshit about their warranty I'd be happy. I'd possibly have a
new auto every 5000k's unless they build a good one. I have a supposed
10,000k/12month warranty on this one. I am sure warranty won't get honoured
as it never does with performance stuff.
My dad builds gearbox's for a livingnot autos though. Although the box's he
does are mainly your common garden variety box's. He reckons the toploader
will do the job easy. As for the T5 not sure. Rod Hadfield recommends a
Tremec 5 speed but @ a cost of $3940 for the box/$180 for the bellhousing
and you need need all the extra toploader stuff. Not sure what the extra's
are but Rod said he has them. Tremec's build to handle 450hp Rod Hadfield
says.
Just put the Tremec off my list. Way out of my budget.
Mechanic's checking out my auto tomorrow. Then I don't know whats going to
happen. He reckons the govenor is faulty. I won't let him rebuild it. I've
already blown too of his autos and he doesn't honour warranty.
Can anyone suggest a place that will honour a warranty on an auto? I
wouldn't know how to hurt an auto. They change gears themselves. All you
have to do is steer. I even lock mine into lower gears so the convertor
locks up and doesn't overheat the auto.
I've got the biggest B&M transcooler available too.
This auto doesn't slip in 1st or 2nd. I can start a burnout in 1st and 2nd
easy. So no clutch slip. Auto refuses to change automatically but will
manually select 1st and 2nd. Won't go into top. Top seems to be a neutral.
I've serviced the auto and replaced the modulator as it was faulty and
leaking fluid into the modulator and manifold.
Brenden
"atec77(nospam)" <"atec77(nospam)"@(remove)hotmail.com> wrote in message
news:3cbb9612$0$11448$afc3...@news.optusnet.com.au...
Brenden
a 6cyl M20. Massive difference in strength.
Brenden
"Brenden" <bw...@bigpond.net.au> wrote in message
news:x4Pu8.13082$o66....@news-server.bigpond.net.au...
atec77(nospam)
Noddy
> Should also add some people break what they think are M21's but are
actually
> a 6cyl M20. Massive difference in strength.
Not really.
The only real difference is the size of the input shaft diameter for the V8
version, and aside from that they're both about as piss weak as each other
and can be broken quite easily behind an average red motor.
Incidentally, M20 & M21 refers to the ratio's, not the type of engine it's
built for. You could get either for both 6 cylinder & V8.....
Regards,
Noddy.
Brenden
Brenden
"atec77(nospam)" <"atec77(nospam)"@(remove)hotmail.com> wrote in message
news:3cbbce45$0$11449$afc3...@news.optusnet.com.au...
Noddy
> Whats pissing me off is paying cash for idiots to built autos that don't
> last. $3000 so far. I'd like to keep and auto but my finances can't afford
> to keep paying for them.
Then perhaps it's time you found an auto rebuilder who knows his shit. The
C10 is a good transmission and the moderate power levels you're making are
well within it's limits. Still, if it were mine I'd go for an FMX, as
they're a much better transmission that can handle considerably more torque
than any of the C series boxes.
If you really want the ultimate in auto boxes without fear of failure, get
yourself an adapter and fit a Powerglide in the car. As far as auto's go,
nothing get's close to them...
Regards,
Noddy.
Noddy
> Can anyone suggest a place that will honour a warranty on an auto? I
> wouldn't know how to hurt an auto. They change gears themselves. All you
> have to do is steer. I even lock mine into lower gears so the convertor
> locks up and doesn't overheat the auto.
You don't have a lock up converter in your car unless you had one
specifically built for it, and having a 3500rpm stall speed converter in a
street driven car is the quickest way to kill an auto around :)
Regards,
Noddy.
Brenden
3500rpm histall it'd be slipping everywhere I drove. That'd kill it nice and
quick.
Thats how I killed my 2nd C10/9/4. 3.0 diff ratio. Convertor only locked up
@ illegal speeds. So I burnt out all the clutches.
Brenden
"Noddy" <das...@optushome.com.au> wrote in message
news:a9glpr$2s74o$1...@ID-132740.news.dfncis.de...
Brenden
doesn't destroy autos. Otherwise I'd throw my 3.0's back in.
I've been told by various places. The setup I have should be reliable. As
power output isn't too excessive. Though it will rise but not by much maybe
40-50hp. They've all said provided the convertor locks up your pretty safe.
If I drove past you? You'd just think I was being silly as the engine would
be sitting around 3500-4000rpm. Unfortunately thats what it takes for the
clutches to stop slipping.
Brenden
"Noddy" <das...@optushome.com.au> wrote in message
news:a9gm27$2vcf3$1...@ID-132740.news.dfncis.de...
atec77(nospam)
street and it sure did me .
Brenden
with a 3500. As it's supposed to have a 4400.
2200 would be fine provided the cam came in a 2000rpm. What cam was in your
car running a 2200?
Here's my cam specs (Cam dynamics/Crane)
MECHANICAL - Rough idle, good mid range H.P. in well developed engine. All
normal modifications required.
BASIC RPM 3800-7000
CAM USE : Strip
GRIND NO. CD248-52
PART NO : 972846
LIFTERS : 99257-16
Deg. Dur. & .050 Cam Lift Int. Exh : 248/248
Deg. Adv. Dur. Int. Exh. : 312/323
Deg. Lobe Separation : 108
Running Clearance -Hot- Int. Exh : .25/.25
Gross Valve Lift Int : .580/.606
Brenden
"atec77(nospam)" <"atec77(nospam)"@(remove)hotmail.com> wrote in message
news:3cbbe864$0$17282$afc3...@news.optusnet.com.au...
Brenden
wasn't achievable without it. In 1988 a machine shop in Dandenong had a
write up about it in Street machine. They engine dyno'd it @ 416hp.
Brenden
"Brenden" <bw...@bigpond.net.au> wrote in message
news:q6Su8.13562$o66....@news-server.bigpond.net.au...
atec77(nospam)
toss the cam and go get a stoker kit , add the correct can and suddenly
the 2200 is purfect. and Id suggest you can then run an auto.
looks to me if you making to many revs , as Ive said b4 you can move
stuff with torque , its torque that makes thing accelerate out of
corners and breaks axles..
Nodd , comments ?.
Brenden
in not a standard stroke/bore 351.
A 378 maybe in order though. About $3000 and 500-550hp later (to get this I
need the same cam). I want more power 400hp flywheel is weak as. I don't
want to have to go to the trouble of engineers certificates. Car/driveline
owes me $18,500. I like driving the car though. It's not as boring as my
Hyndai S-Coupe and EL Falcon.
Tossing the cam drops me down to 350max flywheel which isn't what I am
after. The cars actually quiet nice to drive around the street. The engines
no drama. the power/weight ratio is good. Fuel economy is good. The
driveline is just letting the engine down. I may even put a 4.86 diff in.
We'll see how it goes at the mechanics tomorrow. He keeps telling me he's
built loads of cars with this combo & mines always coming back to bite him
on the arse.
The car was built to race but not race only. It's my toy and relaxation.
Wife and kid's are stressfull.
My mate has a similar spec 351 running 3.7 gears and a 3000rpm stall. Hasn't
had a single auto drama. All built by the same place. Mines just being a
pain I reckon?
One day if I find a TE/TF V8 engineered Cortina rolling shell? I'll throw
the engine in that. I did co-own a 302 Windsor TE Cortina once. Was a fun
car.
My main aim is to eventually get the car to Calder Park. Should run 12's.
I've tested it @ only 13-13.3's. Which isn't bad as the current tyres are
woeful. Then enventually maybe run a 150hp shot of NOS then it should tumble
into 11's.
Brenden
"atec77(nospam)" <"atec77(nospam)"@(remove)hotmail.com> wrote in message
news:3cbbef21$0$11451$afc3...@news.optusnet.com.au...
Noddy
> That's why I have 4.11 diff gears. To make sure the convertor locks up and
> doesn't destroy autos. Otherwise I'd throw my 3.0's back in.
>
> I've been told by various places. The setup I have should be reliable. As
> power output isn't too excessive. Though it will rise but not by much
maybe
> 40-50hp. They've all said provided the convertor locks up your pretty
safe.
>
> If I drove past you? You'd just think I was being silly as the engine
would
> be sitting around 3500-4000rpm. Unfortunately thats what it takes for the
> clutches to stop slipping.
I don't understand what you're talking about here. Do you mean the auto's
clutches or are you talking about clutches in a specifically designed lock
up converter?
For the transmission you have, lock up converters don't exist and the only
way you could get one is to have one specifically built for it which would
be a pretty expensive exercise and something that doesn't sound like you've
done. If you're talking about clutch pack failures in the transmission
itself, then that's most likely to be your converter stall speed is too high
for the friction material being used. What ever rear axle ratio you run will
make absolutely no difference.
With a 3500rpm converter and a 4.11 rear axle, I'll bet it's a pig to drive
around town :)
Do I think you're being silly? absolutely, as there is no way I would drive
a car on the street with a converter stall speed of 3500rpm and hope the
equipment had any chance of a reasonable life, as it won't. If you want your
transmission to last longer than a few months, get rid of the ridiculous
converter and go back to something respectable of around 2000rpm stall speed
and you'll have no problems.
Regards,
Noddy.
atec77(nospam)
with a 351 clevo and it idles at 800 rpm , just a stroker . 2v heads
opened up and a mild cam . and a holley :_)
a bloody huge one.
perhaps you may need to think about an injection set-up off a
windsor.. some time
Noddy
> there you have it, not a cam suitable for a street drive id suggest.
> toss the cam and go get a stoker kit , add the correct can and suddenly
> the 2200 is purfect. and Id suggest you can then run an auto.
> looks to me if you making to many revs , as Ive said b4 you can move
> stuff with torque , its torque that makes thing accelerate out of
> corners and breaks axles..
> Nodd , comments ?.
I agree absolutely.
It sounds as if Brendan's trying to make all of his power through the bump
stick, and that ain't the way to go if it's going to be a car you drive on
the street.
Regards,
Noddy.
Noddy
> Should add this cam was installed as I wanted 400hp @ the flywheel. It
> wasn't achievable without it. In 1988 a machine shop in Dandenong had a
> write up about it in Street machine. They engine dyno'd it @ 416hp.
Firstly, you should bear in mind that cam specs only give you a general
idea, and what particular profile works well in one engine may be a pig in
yours unless you're running identical hardware everywhere else.
For the power output your aiming at, the cam profile seems to be pretty
radical and it doesn't look like something I'd pick personally. I mean, be a
bit realistic here. A standard Phase III Cleveland made close to 400
flywheel horsepower with nothing near as wild as that which allowed it to
have a reasonable idle, and it was quite possible to run "out of the box"
auto's behind them without the slightest difficulty. Perhaps you could list
the rest of your engine's specs to give us some idea?
Some engines have particular traits where they benefit from modifications in
certain areas more than others, and the Cleveland is definitely one of them.
They generally like as much compression as you can give them on the
available fuel, and they like shitloads of airflow. If you're running a
single four barrel carb, the *best* manifold you can buy is a Weiand
Xellerator, and 4V heads are the only way to travel if you wish for it to
mumbo up high.
The good thing about Clevelands is that they have very good airflow
capability as standard, and you don't need to go very radical on the
camshaft to make them work. It's very easy to over cam a Cleveland, and to
me it sounds exactly like what you're doing. The combination of good
compression, a good manifold, a pair of 4V heads, a moderate camshaft and a
decent set of pipes will give you your 400hp quite easily without the car
having to be a pig to drive or destroying automatic transmissions.
GT Falcons sorted all this shit out for you 30 years ago, and all you have
to do is look at their specs for an excellent starting point.
Regards,
Noddy.
Marty Hogan
> That's why I have 4.11 diff gears. To make sure the convertor locks up and
> doesn't destroy autos. Otherwise I'd throw my 3.0's back in.
>
> I've been told by various places. The setup I have should be reliable. As
> power output isn't too excessive. Though it will rise but not by much
maybe
> 40-50hp. They've all said provided the convertor locks up your pretty
safe.
>
> If I drove past you? You'd just think I was being silly as the engine
would
> be sitting around 3500-4000rpm. Unfortunately thats what it takes for the
> clutches to stop slipping.
Brenden, I had a similar conversation with you before, its kind of hard to
explain, but I think you have the fundamental operation of a torque
converter confused, someone else will explain it better then me, but the rpm
range means thats the rpm it will allow it to do above the rpm of the shaft
that comes out of the torque converter, it doesnt ever actually lock up,
just reaches the point that it doesnt allow any more slip, its slipping at
ALL engine rpm's, not just ones below its stall speed. Noddy will explain it
better if he can be bothered im sure :)
Brenden
would cause the engine to fuel up. Then the engine may stall. Then I'd get
piles of abuse because the cars stalled/flooded and I am stuck @ an
intersection.
Brenden
"atec77(nospam)" <"atec77(nospam)"@(remove)hotmail.com> wrote in message
news:3cbbf77c$0$11451$afc3...@news.optusnet.com.au...
Brenden
Engine specs are;
351 crank & rods
Forged pistons 10.5:1 compression ratio
Ported/polished 302 closed chamber heads 77cc's flow tested @ 600hp max.
Running 4v valves.
1.73 rocker ratio with 60thou oversize pushrods.
Roller rockers
750DP HP Holley Carb
Weiand X-Cellator single plane manifold
Engine only runs on 98+ Octane pump fuels
Timing is 34 degrees advanced.
To sort of give you an idea on how nice it runs. Cold start 2 pumps of
accellerator and it started and idles. The car has no choke.
Warm start = no accellerator at all to start.
It idles relatively smooth for the cam profile.
To get any more power I need to spend a further $3000 on a 378 stroker
bottomend or run higher compression. I've already spent $11,500 (from sump
to carb). I started from scratch. Everything had to be new. My mates had
heaps of problems with secondhand parts.
I can get my hands on a set of 4V heads but I don't think they'll flow any
better than this set already is. Current set of heads was done by WOG
engineering here in Vic.
The bottomend will hold about 7000rpm max. I've had it @ 7500 but I could
tell the power/torque curve was long gone.
Brenden
"Noddy" <das...@optushome.com.au> wrote in message
news:a9gu5p$33ss8$1...@ID-132740.news.dfncis.de...
Brenden
Driving along @ 2000rpm. I give it a bootfull. The rpms will jump rapidly to
3500 then slowly climb. As the convertor is locked up (enough pressure to
push the car forward rapidly).
But driving along @ 4000rpm if I give it a bootfull the rpm doesn't climb
rapidly as the convertor is locked up. Instead of just revving up the car
speed increases.
Brenden
Think I understand it? Maybe I've lost the plot. I know zero about auto's. I
can do manuals and engines etc but not auto's.
"Noddy" <das...@optushome.com.au> wrote in message
news:a9gspc$33tg3$1...@ID-132740.news.dfncis.de...
Brenden
(no slippage) provided the rpms are above the stall speed.
I spoke to quite a few people regarding stall convertor speed (but not
function) and diff ratio selection before begining to build the driveline. I
am begining to think I've been misinformed.
Brenden
"Marty Hogan" <rap...@as-if.com> wrote in message
news:a9h22v$36bg7$1...@ID-132934.news.dfncis.de...
Dene Oehme
>Then perhaps it's time you found an auto rebuilder who knows his shit. The
>C10 is a good transmission and the moderate power levels you're making are
>well within it's limits. Still, if it were mine I'd go for an FMX, as
>they're a much better transmission that can handle considerably more torque
>than any of the C series boxes.
My suggestion exactly for the relatively low power he is making.
Regards
Dene Oehme
http://members.ozemail.com.au/~waterline/
"Physics is physics no matter where or how you do it" Me - 20/1/2001
Dene Oehme
>As for my driving style. I built the car for street/strip.
Yet you use a trimatic?? Good choice....NOT.
>My current situation is 240rwhp/4.11 gears/C4 with 3500histall thats 5
>months old max. Not one auto seems to do the job for longer than 5000k's.
Again.... A bad choice in autos for your kind of work.
Also.. at first glance 240hp does not sound like enough power to
warrant 4:11 gears and a 3500 converter. Sounds like some
miss-matching here to me.
Dene Oehme
>Thats how I killed my 2nd C10/9/4. 3.0 diff ratio. Convertor only locked up
>@ illegal speeds. So I burnt out all the clutches.
That statement shows a fundermental missunderstanding of how an auto
works. Where, when and how the converter " locks up" will have no
direct effect on any clutch deterioration in the trans itself.
Particularly in the transmissions you are talking about.
Dene Oehme
>You don't have a lock up converter in your car unless you had one
>specifically built for it, and having a 3500rpm stall speed converter in a
>street driven car is the quickest way to kill an auto around :)
How do you figure Noddy?
Dene Oehme
>I've been told by various places. The setup I have should be reliable. As
>power output isn't too excessive. Though it will rise but not by much maybe
>40-50hp. They've all said provided the convertor locks up your pretty safe.
But your convereter never actually locks up does it. I mean.. It
doesn't have a lock up clutch so it will always be "slipping" to some
extent. The fact that they use sloppy terminology like that makes me
wonder how good they are for a start.
>If I drove past you? You'd just think I was being silly as the engine would
>be sitting around 3500-4000rpm. Unfortunately thats what it takes for the
>clutches to stop slipping.
Which clutches are slipping? In an earlier post you said it the
clutches weren't slipping.
Noddy
> Hi Noddy,
Hi Brendan...
> Engine specs are;
>
> 351 crank & rods
> Forged pistons 10.5:1 compression ratio
> Ported/polished 302 closed chamber heads 77cc's flow tested @ 600hp max.
> Running 4v valves.
> 1.73 rocker ratio with 60thou oversize pushrods.
> Roller rockers
> 750DP HP Holley Carb
> Weiand X-Cellator single plane manifold
> Engine only runs on 98+ Octane pump fuels
> Timing is 34 degrees advanced.
Sounds like a nice engine. Wish I had it in my EF :)
> To get any more power I need to spend a further $3000 on a 378 stroker
> bottomend or run higher compression. I've already spent $11,500 (from sump
> to carb). I started from scratch. Everything had to be new. My mates had
> heaps of problems with secondhand parts.
A stroker kit would probably be nice, but I don't think that's you're only
choice for improvements. The possibilities are only limited to the amount of
money you're prepared to throw at it, suffice to say that I know of a few
*very* high horsepower Clevelands. They can be a tad on the expensive side,
but you get very little for free....
> I can get my hands on a set of 4V heads but I don't think they'll flow any
> better than this set already is. Current set of heads was done by WOG
> engineering here in Vic.
I'm not familiar with them, but I will go on record as saying that a
properly prepped pair of 4V heads will outflow almost anything in existence
on any engine up to around 400 cubic inches, including the 2V's you've got
already, and if you're prepared to spend 3 grand on a stroker kit, that kind
of money would get you a banger set of well prepped heads that will make the
thing scream over 4000rpm. Of course, you'd have to factor in the cost of a
4V version of the X-Cellator or perhaps stretch your budget to allow for a
programmable EFI configuration.
The only disadvantage to 4V heads, and particularly those that flow well in
the exhaust port, is that they make normal low rpm driving somewhat
lacklustre. Still, that doesn't sound like something that would bother you
all that much given your current configuration.
I had a 4V equipped Cleveland in an XP Coupe many years ago, and it was a
nothing engine in my opinion. It ran around 11:1 compression, modified crank
for internal balance, a very good set of heads, an X-Cellator with an 850
Holley, a Viking 100H camshaft. and an excellent set of pipes made by a
friend of mine. It didn't have anything "plush" like roller rockers or
custom balancers as I couldn't afford them, and it made over 500hp on the
dyno.
Regards,
Noddy.
Dene Oehme
>get rid of the ridiculous
>converter and go back to something respectable of around 2000rpm stall speed
>and you'll have no problems.
Agreed. I'd be getting something that stalled at about 2200 and it
will work. My next step would be to get rid of the lumpy idle wanker
cam and use soemthing more reasonable.
atec77(nospam)
Dene Oehme
>Sean @ Proconvertors explained it as if the convertor did completely lockup
>(no slippage) provided the rpms are above the stall speed.
Then Sean's having you on.
>I spoke to quite a few people regarding stall convertor speed (but not
>function) and diff ratio selection before begining to build the driveline. I
>am begining to think I've been misinformed.
It's a common mistake to make. My brotherin law had a 308 HQ monaro
with 4:11s and a converter that stalls similar to yours. He bought it
as was from a guy who thought he was an expert on HP engines and so
forth. He was displeased with it's drivability in general and what he
considered to be a lack of acceleration out of an engine with
suposedly about 240 at the rear wheels. I advised him to either
change the converter to one at about 2200 or change the diff ratio to
either 3.5 or around 3.7.
One weekend we pulled out the trans and changed the converter. That
did it. A totally different car to drive. Heaps better acceleration
without revving the tits out of the engine each time and for general
driving - far more enjoyable..
Dene Oehme
>Sean @ Proconvertors explained it as if the convertor did completely lockup
>(no slippage) provided the rpms are above the stall speed.
I should have added - you can prove he's wrong for yourself.
Get the car going with the revs well above the claimed stall speed.
Then boot it but not so far as to make the trans downshift. Do the
revs suddenly jump by at least a few hundred rpm? I think so. That's
not locked then is it?
Noddy
> Sean @ Proconvertors explained it as if the convertor did completely
lockup
> (no slippage) provided the rpms are above the stall speed.
>
> I spoke to quite a few people regarding stall convertor speed (but not
> function) and diff ratio selection before begining to build the driveline.
I
> am begining to think I've been misinformed.
It sounds like it.
The stall speed of a converter basically refers to the maximum speed the
converter can be spun before the input shaft of the auto will be turned. In
other words, if you're preparing your car for a hard launch by holding the
brake and locking the driveline, you should theoretically be able to spin
the engine to 3500rpm (as is the case with your converter) before the
turbine in the converter starts to drive the input shaft and move the car.
This is called torque multiplication.
Think of it like having a manual transmission equipped car, and you want to
launch it as quickly as possible. Naturally, you'll rev the engine up higher
than normal so the rpm is at a good enough point to stop the engine from
bogging down and getting you away as quickly as possible as soon as you
release the clutch. A high stall torque converter achieves exactly the same
thing, in that it allows the engine to be revved to a good point in it's
power range before applying force to the input shaft and, hence, turning it
with as much torque as possible for a quick launch.
The downside to high stall torque converters, and it's a huge one, is that
while they're great for the times when you want a hard launch, they're shit
house at all other times as they slip their guts out under stall speed and
burn the crap out of the transmission fluid while doing so. Unlike a manual
where you can launch the car at whatever rpm you like, a high stall speed of
a converter is a fixed constant that only has any real benefit to you with
you foot flat on the throttle. At all other times they're quite useless and
can do damage to the rest of an auto in a street driven car as the fluid
gets the living shit knocked out of it in no time flat, regardless of how
big a cooler you run.
I suspect that most of your auto problems would disappear with a change of
converter stall speed.
Regards,
Noddy.
Dene Oehme
>The stall speed of a converter basically refers to the maximum speed the
>converter can be spun before the input shaft of the auto will be turned.
Yes and no. I mean... you can idle away from the lights at very light
throttle with a converter that stalls at 5000 and the car will move
off at only a few hundred rpm above idle or even at idle.
Basically the only time a converter is truely stalling is at full
throttle with the trans input shaft locked. This happens of course
when you are stalling up at the lights just before take off for a run
but rarely at any other time.
>This is called torque multiplication.
Well............ not really. Torque multiplication is occuring under
stall conditions but it is not the only time that the action of the
stator in the converter is causing torque multiplication so it would
be inaccurate to reffer to torque multiplication and converter stall
as the same thing.
>in that it allows the engine to be revved to a good point in it's
>power range before applying force to the input shaft and, hence, turning it
>with as much torque as possible for a quick launch.
but it is applying force to the input shaft the whole time. The only
thing stopping the input shaft from turning at virtually any throttle
setting is your foot on the brake pedal.
>I suspect that most of your auto problems would disappear with a change of
>converter stall speed.
As I said elsewhere. I agree and that would be my first
recomendation.
Noddy
"Dene Oehme" <wate...@ozemail.com.au> wrote in message
> How do you figure Noddy?
Mainly because something with a stall speed of around 3500rpm is going to be
burning the shit out of the fluid 99% of the time in a street driver, and
whenever you stand on the throttle hard from idle it's going to twist the
crap out of the input shaft and place a shitload of instant torque on the
trans.
Not impossible to handle with the right level of preparation and equipment,
but durability will suffer no less...
Regards,
Noddy.
Noddy
> What I mean is for example :
>
> Driving along @ 2000rpm. I give it a bootfull. The rpms will jump rapidly
to
> 3500 then slowly climb. As the convertor is locked up (enough pressure to
> push the car forward rapidly).
>
> But driving along @ 4000rpm if I give it a bootfull the rpm doesn't climb
> rapidly as the convertor is locked up. Instead of just revving up the car
> speed increases.
This is where you're getting confused.
The converter doesn't actually "lock up", but rather it free wheels until it
reaches stall speed where it creates enough centrifugal force to drive the
turbine and spin the input shaft. The engine goes from a free revving no
load condition under stall speed, to being pulled down by the load on the
crank as the impellor and turbine (the two main parts of a converter) start
to match speed and drive the car, which is what happens when you're driving
along at 2000rpm and you give it a bootful. If you're driving at 4000rpm and
give it some, the engine's not going to accelerate as quickly as the stall
speed has already been exceeded and the turbine is being driven as hard as
it can. There's no "slack" to be taken up....
Unless you specifically have a converter with a lock-up clutch device (which
I don't think you do), the converter is never locked at any speed, and
normally drives the auto's input shaft at 9/10th's of crankshaft rpm.
In other words, there is *always* slip....
Regards,
Noddy.
Noddy
"Dene Oehme" <wate...@ozemail.com.au> wrote in message
> Yes and no. I mean... you can idle away from the lights at very light
> throttle with a converter that stalls at 5000 and the car will move
> off at only a few hundred rpm above idle or even at idle.
Of course.
I should have been more specific and said that it's the maximum speed at
which the input shaft can be *held*. If it didn't turn the shaft at all, you
wouldn't be able to move the car under stall speed rpm...
> Basically the only time a converter is truely stalling is at full
> throttle with the trans input shaft locked. This happens of course
> when you are stalling up at the lights just before take off for a run
> but rarely at any other time.
Absolutely, and it's the single reason why high stall torque converters are
such a pain in the arse on a street driven car
> Well............ not really. Torque multiplication is occuring under
> stall conditions but it is not the only time that the action of the
> stator in the converter is causing torque multiplication so it would
> be inaccurate to reffer to torque multiplication and converter stall
> as the same thing.
Agreed, but I was just trying to keep it simple.
> but it is applying force to the input shaft the whole time. The only
> thing stopping the input shaft from turning at virtually any throttle
> setting is your foot on the brake pedal.
It is indeed, but most modified converters don't do much until they get
close to stall speed where they come on like the gangbusters. When they do,
you've hopefully picked a stall speed to suit your engine's output and one
that will get your car moving as quickly as possible without pulling the
engine down.
Regards,
Noddy.
Brenden
but atleast I already have stainless valves/double valve springs/etc. Only
thing I'd have to prep on the 4V's is port/polish/guides and seats.
Not including 4V head purchase that'd cost about $1000.
Stroker short motor is $3000. It's $2000 just for the crank/rods/rings and
pistons.
Then another $500-$600 for a manifold.
11:1 is a no no these days. No pump fuel has enough octane to stop the
detonation. Already been there and done that. Low rpm seems okay then high
rpm pings like crazy.
Brenden
"Noddy" <das...@optushome.com.au> wrote in message
news:a9h6jb$36u62$1...@ID-132740.news.dfncis.de...
Brenden
twin system. So figures will rise.
Brenden
"Dene Oehme" <wate...@ozemail.com.au> wrote in message
news:3cbc17b...@news.ozemail.com.au...
DAN
I think your engine builder miss matched your cam Brendan!
DAN
"atec77(nospam)" <"atec77(nospam)"@(remove)hotmail.com> wrote in message
news:3cbbf77c$0$11451$afc3...@news.optusnet.com.au...
Dene Oehme
>> How do you figure Noddy?
>
>Mainly because something with a stall speed of around 3500rpm is going to be
>burning the shit out of the fluid 99% of the time in a street driver,
One should considder (or have been told by the supplier) the extra
problems that a high stall converter bring with it. For one thing you
certainly should change the fluid a lot more often than once a year if
it is doing heavy work. When my mates and I used to drag our cars,
we used to change the fluid after each drag meeting. Most of the time
on the street you're not driving it that hard ( one would hope) so the
fluid lasts ok the rest of the time. Basically if you're just
cruising around at normal city/susburbs driving pace and
accelerations, the fluid will not deteriorate much quicker at all with
a high stall than a standard converter. Most people with high stall
converters don't tend to drive like that all the time so it needs to
be changed more often.
> and
>whenever you stand on the throttle hard from idle it's going to twist the
>crap out of the input shaft and place a shitload of instant torque on the
>trans.
But there's not really any circumstances where it will get instant
torque like when you drop the clutch in a manual. The torque always
gets applied over a period of time ( albeit fairly short sometimes)
and therefore there's not the (relatively) instant shock loading you
get on the input shaft of a manual trans. This is one reason why
input shafts on autos for a given HP range are often smaller diameter
than their manual counterparts.
Compare the input shaft diameter on a C4 or FMX to the input shaft on
Fords manual gearboxes for the same power range.
If the trans if breaking input shafts then you've chosen the wrong
trans. If it.s burning out forward clutches or destroying the sprag
clutch either the same applies or you didn't built it tough enough.
Brenden
would. The engine rebuilder and I have simulated hp on software (Dyno 2000
from www.mrgasket.com.au). We couldn't find a cam any smaller to do the same
power.
I just can't see another cheap way around this other than blowing $15000 on
a full rebuild again. There's no change of that. The money is gone.
Brenden
"DAN" <ydou...@yahoo.com> wrote in message
news:_43v8.12$xy6....@nsw.nnrp.telstra.net...
Noddy
"Dene Oehme" <wate...@ozemail.com.au> wrote in message
> One should considder (or have been told by the supplier) the extra
> problems that a high stall converter bring with it. For one thing you
> certainly should change the fluid a lot more often than once a year if
> it is doing heavy work. When my mates and I used to drag our cars,
> we used to change the fluid after each drag meeting. Most of the time
> on the street you're not driving it that hard ( one would hope) so the
> fluid lasts ok the rest of the time. Basically if you're just
> cruising around at normal city/susburbs driving pace and
> accelerations, the fluid will not deteriorate much quicker at all with
> a high stall than a standard converter. Most people with high stall
> converters don't tend to drive like that all the time so it needs to
> be changed more often.
I essentially agree with what you're saying here, but I find that the
"damage" to the fluid increases
exponetially as the stall speed goes up.
For example, if you have your average street "hottie" with a 2500rpm
converter, it's most likely not going to cause you too many problems as
that's an engine speed that you'd see often with normal daily driving.
However, 3500rpm is a diferent story for normal daily use, as the impellor &
turbine are going to be at quite different speeds for a lot of the time, and
generating a lot of heat while they are. It won't kill the fluid in five
minutes, that's for sure, but it certainly gives it a harder time than a
more respectable conveter would and it's something that needs to be taken
into account.
> But there's not really any circumstances where it will get instant
> torque like when you drop the clutch in a manual. The torque always
> gets applied over a period of time ( albeit fairly short sometimes)
> and therefore there's not the (relatively) instant shock loading you
> get on the input shaft of a manual trans. This is one reason why
> input shafts on autos for a given HP range are often smaller diameter
> than their manual counterparts.
Not "instant" as in a manual clutch dump, no, but fairly rapid and compunded
compared to a standard auto.
> Compare the input shaft diameter on a C4 or FMX to the input shaft on
> Fords manual gearboxes for the same power range.
That's true, and as you say they're "loaded" all the time in standard
applications and don't get the massive instant "bang" of a manual input
shaft, but they can run into trouble once that load goes from virtually
nothing to a huge hit and a milisecond with a big jump on the pedal.
> If the trans if breaking input shafts then you've chosen the wrong
> trans. If it.s burning out forward clutches or destroying the sprag
> clutch either the same applies or you didn't built it tough enough.
I largely agree except for the input shaft issue. I used to break Powerglide
input shafts all the time with a trans brake, but had no problems once I had
a shaft made out of a high quality material. The rest of the trans was fine
and never gave me an ounce of trouble.
Regards,
Noddy.
DAN
> To get any more power I need to spend a further $3000 on a 378 stroker
> bottomend or run higher compression. I've already spent $11,500 (from sump
> to carb). I started from scratch. Everything had to be new. My mates had
> heaps of problems with secondhand parts.
Faaarrrr out! to get 235rwhp from my lil ol 5L Holden donk it cost me half
that much!
DAN
Brenden
Same motor in a Commodore costs about $7000-$8000max. Inc new sump/manifold
and carb etc.
Brenden
"DAN" <ydou...@yahoo.com> wrote in message
news:qX6v8.37$xy6....@nsw.nnrp.telstra.net...
DAN
that's why you don't see as many hot Fords around as Holdens.
DAN
"Brenden" <bw...@bigpond.net.au> wrote in message
news:dn8v8.17344$o66....@news-server.bigpond.net.au...
Dene Oehme
>but they can run into trouble once that load goes from virtually
>nothing to a huge hit and a milisecond with a big jump on the pedal.
But they don't really do that do they. You jump on the pedal and
immidiately the car starts to move. The engine doesn't sort of free
rev up to 3500 before there's any drive. The car starts to move at
much lower revs. Also the engine may take 1/4 of a second or more to
get up to 3500 under load. So the input shaft and trans in general is
loaded up much smoother, even with high HP and high stall than
dropping the clutch in a manual. The shock loads are far less.
The only time what you've said above really applies is if someone is
stalling up the converter and instead of taking it up to the stall
speed gradually over a second or so, just instantly floors it with the
brakes on. A stupid thing to do and I'd laugh at the iminent
destruction they'd cause.
>> If the trans if breaking input shafts then you've chosen the wrong
>> trans. If it.s burning out forward clutches or destroying the sprag
>> clutch either the same applies or you didn't built it tough enough.
>
>I largely agree except for the input shaft issue. I used to break Powerglide
>input shafts all the time with a trans brake, but had no problems once I had
>a shaft made out of a high quality material.
Yea, so initially you didn't build the trans strong enough.
Brenden
weight of the Commodore against the weight of a Falcon.
Everyone goes got the lightest car they can and thenworks on the highest hp
they can produce within a budget.
Brenden
"DAN" <ydou...@yahoo.com> wrote in message
news:Cu8v8.44$xy6....@nsw.nnrp.telstra.net...
Noddy
> But they don't really do that do they. You jump on the pedal and
> immidiately the car starts to move. The engine doesn't sort of free
> rev up to 3500 before there's any drive. The car starts to move at
> much lower revs. Also the engine may take 1/4 of a second or more to
> get up to 3500 under load. So the input shaft and trans in general is
> loaded up much smoother, even with high HP and high stall than
> dropping the clutch in a manual. The shock loads are far less.
They are indeed, but they're still significantly higher than those of a
standard converter, and that's the point I was making.
> The only time what you've said above really applies is if someone is
> stalling up the converter and instead of taking it up to the stall
> speed gradually over a second or so, just instantly floors it with the
> brakes on. A stupid thing to do and I'd laugh at the iminent
> destruction they'd cause.
Me too :)
> Yea, so initially you didn't build the trans strong enough.
Maybe, but it definitely wasn't the wrong trans for the job.
Regards,
Noddy.
Kieron Murphy
wrote:
>Yep Ford motors cost more to build than Holdens. Pretty common knowledge.
>
>Same motor in a Commodore costs about $7000-$8000max. Inc new sump/manifold
>and carb etc.
>
But is that comparing apples with apples Brenden? like your donk has
got some top gear inside it, I would guess you could build a 240rwhp
351 a fair bit cheaper if you went with less exotic items, Noddy got
500 fly with basic mods.
I vaguely recall Mick Webb selling 351's for around the $4-5k mark
with hp in the 300+ range.
Still, in general though, Ford are traditionally more expensive to
build.
Kieron
Dene Oehme
>> Yea, so initially you didn't build the trans strong enough.
>
>Maybe, but it definitely wasn't the wrong trans for the job.
No, you're right of course. That's the troble with making
generalizations isn't it.
Noddy
> generalizations isn't it.
Point taken and acknowledged :)
Regards,
Noddy.
Dene Oehme
>> No, you're right of course. That's the troble with making
>> generalizations isn't it.
>
>Point taken and acknowledged :)
Actually I meant my generalization that if you've got input shafts
breaking then you've chosen the wrong trans.
Dene Oehme
>but if someone said to me build one with more torque
>multiplication etc, well I would be doing a lot of trial and error till
>I got it right.
I've always been under the impresion that the torque multiplication
capability of a torque converter, is as much as times 2, is that way
by design ex factory and there's not really a lot that can be done to
change the amount of torque multiplication that a converter is capable
of.
Usually in torque converter modification the main things they
concentrate on are stall speed, strength and tighter end thrust
clearances.
>As it was explained to the idyit apprentice at batman, 4 cylinder cars
>have a higher stall (they used the starfire as the example) or what
>would translate into a higher stall
It actually was a higher stall when behind a starfire even because the
torque curve of the engine of those motors was higher than the Holden
6. Therefore they needed the converter to stall at a higher speed so
that the engine got a chance to develop some torque before it was
expected to do any work.
> ........ by saying that the starfire was sufficiently gutless that
>it really...........
..........needed a higher stall converter to compenstae for it's lack
of bottom end grunt.
>Having said that, the place that has done more than a couple of
>convertors for me actually attempts to ge the stall speed up via
>internal mods, whilst as much as possible (for a streeter) maintaining
>overall size.
The technical term is a "backbend" where they liretally bend the
blades of turbine ( I think?? Could be the impellor??) back by about
45 degrees. It ususlly only results in a stall speed of about 2300 or
so at best. If you need to go higher you have top go to a smaller
converter.
The trouble is most of the smaller converters you get are setup for
around 3200 minimum and it's often really hard to get one that stalls
between 2300 and 3200. Say you wanted one with a stall speed of 2800
you'd probably have to find a torque converter guy that really knows
what he's doing (these can be hard to find) to build one for you.
Noddy
"John McKenzie" <jm...@alphalink.com.au> wrote in message
> I kid you not in the last week or so on the jyturbo list, there has been
> a 'dialogue' with people making serious claims that powerglides are crap
> and a stock c4 would be a better starting point for a high torque turbo
> charged 5 litre (and this is adaptation cost/issues not even being
> considered)
Well, I can kind of understand why people wouldn't want to have a Powerglide
in a daily driver, as their lack of forward ratios tends to make most
vehicles with a moderate power output seem rather lethargic, especially the
V8 versions with the taller first gear. They also happen to have one of the
noisiest planetary gearsets on earth, and can be quite irritating in
anything "quiet".
However, when it comes to strength they're unsurpassable in my humble
opinion, and I honestly cant think of another automatic transmission that
could stand the level of abuse that a 'Glide would be comfortable with for
any length of time without a catastrophic failure. A heavily modified 400,
727 or FMX might get close, but that would probably be about it and I
wouldn't consider any to be the Powerglide's equal in the strength stakes.
I've seen Powerglide's that have been quite successful behind high
horsepower Chev's, Holdens, Fords, Chryslers and I even know of a guy who
runs a 'Glide behind a Nitro burning blown big block in a front engined
junior fueler in the States that's running in the 5.90's or so and I really
doubt that a C4 would be all that successful in such an application :)
> RE: the ford. you could have spent around $1500 and got the same or more
> power with a couple of s/hand turbos (total including engine freshenup).
> The same or more power obviously would mean more torque. Possibly more
> trans issues, but you could have an 1800rpm stall without any drawback.
> You could also run 2.75 or 3.0:1 diff gears. Wouldn't have to see the
> high side or 5000rpm. Just gotta plug the darkside whenever I can.
I agree.
Chasing normally aspirated ponies is often *very* expensive and they can be
quite hard to catch.
Regards,
Noddy.
Noddy
> Agreed, but the guy was looking for options other than a $$$$$ AOD for
> his 5 litre which was supposed to be making mid 600ft/lbs of torque. The
> car is (then again I would drive it on the road) no longer what you
> would call a streeter, and I would think compromises have to be made.
> Either with forward ratios, or go a moderate c4 or something, and be
> more conservative with the torque goals. You do get to a stage (and I
> have seemingly endless dialogue about this) where you make so much
> torque that either (or both) a low geared diff, or indeed first gear in
> and of itself become somewhat worthless - for full power at any rate.
Indeed, and it sounds like this car is the perfect candidate for a Glide
conversion.
> not to mention you'd end up with around 75hp (pulled it out my ass) less
> at the rear wheels just to drive the bloody things. Which should mean
> the powerglide should return a better trap speed.
A very good point.
I've always liked the FMX in most Ford's that have a bit of poke as it's a
pretty good box, but they cost some. The difference in driving an FMX and a
C4 is around 50 horsepower, and that's a fairly big drop. I think it's one
of the reasons why Ford give the things the kyber in favour C series boxes.
> you've obviously never had a car with a borgwarner 35...
Got one in my ZL Fairlane, and the 4.1 EFI is enough to tax it :)
> Must be a bummer living in WA - if it wasn't turbod from the factory, it
> can never be.....
Now, there's grounds for political assassination if ever I saw it....
Regards,
Noddy.