350 Redline?
Laymaster
but when I was coming out of an icy spot, I did hit 5500. Shouldn't an
engine die out or sputter at a redline, or is that only on computer
controlled injection? On a carb, is it possible to push the engine way into
the red?
-Erik
DJMika
>From: "Laymaster" <laym...@monmouth.com>
>Date: 1/29/99 2:04 AM Pacific Standard Time
>Message-id: <78s14a$749$1...@news.monmouth.com>
Erik,
there is no speified redline on a 350. It depends on the individual motor and
how it was built. Stock 350's that were put in camaro's through the years
generaly redlined about 5000 RPM's, some of the new ones are higher. BUT,
unless there is some kind of rev limiter in your computer, which not too many
cars actually have (computer controled, EFI or carbed) you can wind your motor
up until you most certainly break somthing. If this is a problem for you, MDS
makes the 6AL electronic ignition which not only helps economy and power, but
offers a user changable rev limiter, so you can decide what RPM you would like
to be your limit. The MSD is easy to put in, and a great add-on. Although it
will help, it won't make your motor idiot proof, so watch those shifts. good
luck
DJMIKA
1991 RS Camaro
1973 C10 pickup
Kwi...@camaro.com
>On a 5.7 L engine (350 ci) where should the redline be? I've heard 4000,
>but when I was coming out of an icy spot, I did hit 5500. Shouldn't an
>engine die out or sputter at a redline, or is that only on computer
>controlled injection? On a carb, is it possible to push the engine way into
>the red?
Well... I think that on the pre-LT1 350's (before 1993)... the limiter
was right at 5500 RPMS... you should be ok...
On the LT1 the motor can handle up to 6500 RPMS before you start
running into problems...
I hurt mine pretty bad by runnning it up to 7500 RPM on nitrous...
but it happens...
oh well... It's given me a good excuse to rebuild the thing into
a whip ass machine...
Gregory J. Wageman
Laymaster <laym...@monmouth.com> wrote:
>On a 5.7 L engine (350 ci) where should the redline be? I've heard 4000,
>but when I was coming out of an icy spot, I did hit 5500. Shouldn't an
>engine die out or sputter at a redline, or is that only on computer
>controlled injection? On a carb, is it possible to push the engine way into
>the red?
My '87 IROC-Z's 5.7 L redlines at 5500, but that's because that engine
has roller rockers. The 350 in my '74 Nova (RIP) redlined at 4500. The
'87, while computer-controlled, has no rev limiter.
My understanding is that, on a pushrod engine like the Chevy small block,
the first thing that happens as you push the revs beyond redline is "valve
float". The valve train is trying to move so quickly that the valve
springs aren't strong enough to overcome inertia and close them completely
when they should be, and so you lose compression and power, backfire, etc.
--
-Greg
----
Visualize whirled peas.
Bill
handle the rpm's they did before valve float occurred so it will happen at a
lower rpm the next time.
Jeff
converter and gears.
changing any of these or computer paramters changes this.
Jeff.
Kwi...@Camaro.com wrote in message <78s94i$cqf$1...@camel29.mindspring.com>...
>"Laymaster" <laym...@monmouth.com> wrote:
>
>>On a 5.7 L engine (350 ci) where should the redline be? I've heard 4000,
>>but when I was coming out of an icy spot, I did hit 5500. Shouldn't an
>>engine die out or sputter at a redline, or is that only on computer
>>controlled injection? On a carb, is it possible to push the engine way
into
>>the red?
>
HFairow
>>>engine die out or sputter at a redline, or is that only on computer
>>>controlled injection? On a carb, is it possible to push the engine way
>into
>>>the red?
'89 IROC 350....Tach redlines at 5500 but nothing prevents it from going
higher....except common sense which prevails in most instances.
Clint
¶~~K®øñø§~~¶
Brian
this is bad for your engine.. Pushrod engines will generally "float the valves"
way before an overhead cam engine will. This is due to the pushrods actually
deflecting and bouncing off the lifters and damaging the rockers. If you really
want to look for a redline maximum for the 350 you need to look at piston
speeds in terms of feet per minute. You'll quickly find that non pushrod
engines are far superior to the archaic crap that gets pushed off on the public
here in the USA. Pistons speeds, and valve actuation speeds increase to a point
where the engine is capable of producing far more power more efficiently and
cleaner (shh don't tell Bubba) than an archaic single cam and pushrods ever can
reliably produce. With a proper setup an 350 engine could turn well over 14,000
rpms and still hold together. Of course your ill handling machine would plant
your ass into the closest ditch, telephone pole (pick your favorite immovable
object here __________).
Skinny J...
TDeKon
>rpms and still hold together.
Would that proper setup include 100 gram pistons (instead of a more typical
500-600 grams)? What would you ever want a 14K rpm engine for? That is for
small no-torque engines that need to spin that high to produce any significant
power. Do you have any engine design experience? Do you know how big the ports
have to be to flow 350ci of air at that speed without the flow going
supersonic? Do you know the loads on a con-rod at 14K rpms?
> You'll quickly find that non pushrod
>engines are far superior to the archaic crap that gets pushed off on the
>public
>here in the USA.
Superior in what ways?
Lack of low end torque? Lack of peak horsepower? Lack of area under the torque
curve? OHC engines do not have the major advantage you may think.
>Of course your ill handling machine would plant
>your ass into the closest ditch, telephone pole (pick your favorite immovable
>object here __________).
Do you think that non-American cars all handle better than American cars? Have
you driven many examples of both? I have. Ten years ago you might have had a
point. I don't think it is valid today.
>Valve float is usually closely follwed by the valves bouncing off the seats
>this is bad for your engine.. Pushrod engines will generally "float the
>valves"
>way before an overhead cam engine will. This is due to the pushrods actually
>deflecting and bouncing off the lifters and damaging the rockers.
There are quite a few inaccuracies in this quote. You might want to get a good
SAE book on the subject.
Terry
Mechanical/Automotive Engineer
Professional Engine Builder
Laymaster
TDeKon wrote in message <19990202005012...@ng-fq1.aol.com>...
>>With a proper setup an 350 engine could turn well over 14,000
>>rpms and still hold together.
>
>Would that proper setup include 100 gram pistons (instead of a more typical
>500-600 grams)? What would you ever want a 14K rpm engine for? That is for
>small no-torque engines that need to spin that high to produce any
significant
>power. Do you have any engine design experience? Do you know how big the
ports
>have to be to flow 350ci of air at that speed without the flow going
>supersonic? Do you know the loads on a con-rod at 14K rpms?
I'm a bit skeptical about teh 14k RPM's...the only thing i've seen that is
able to get that high is a motorcycle engine, and that's like a ninja or
som'n. From pushing it close to 6k, and then shifting, I think i'll be
shifting at about 5k or 5200, after smelling that metal burning smell when I
got out. Wasn't pretty. =(
-Erik
Laymaster
Laymaster
Laymaster
Laymaster
Laymaster
RacerX
"PHandlon"@worldnet...@worldnet.att.net says...
>
>Valve float is usually closely follwed by the valves bouncing off the seats
>this is bad for your engine.. Pushrod engines will generally "float the
valves"
>way before an overhead cam engine will. This is due to the pushrods actually
really
>want to look for a redline maximum for the 350 you need to look at piston
Hmm. Comparison of pushrod pistons vs. overhead pistons. What's the difference?
Really, the valvetrain is the limiting factor in most engines.
>engines are far superior to the archaic crap that gets pushed off on the
public
>here in the USA. Pistons speeds, and valve actuation speeds increase to a
point
>where the engine is capable of producing far more power more efficiently and
Combustion efficiency depends on valve timing.
>cleaner (shh don't tell Bubba) than an archaic single cam and pushrods ever
can
>reliably produce. With a proper setup an 350 engine could turn well over
14,000
Maybe if a V8 reciprocating assembly wasn't any heavier than one for a
motorcycle. 14k is pushing the envelope for most bikes.
>rpms and still hold together. Of course your ill handling machine would plant
>your ass into the closest ditch, telephone pole (pick your favorite immovable
>object here __________).
>
>Skinny J...
>
Why be confined to immovable objects?
RacerX
"PHandlon"@worldnet...@worldnet.att.net says...
>
BTW, if you want 14,000 rpms, get a turbine.
Kwi...@camaro.com
>This is due to the pushrods actually
>deflecting and bouncing off the lifters and damaging the rockers.
Wrong fuck-o... modern V-8 OHV engines experience valve float around
6500 rpm because they use hydraulic roller cams (to avoid rocker
adjustment while generating good power)... at high RPM the lifters do
not follow cam profile because the valve springs are not strong enough
to keep up at high RPM, due to the step slope / incline of most
hydraulic roller cams....
>If you really
>want to look for a redline maximum for the 350 you need to look at piston
>speeds in terms of feet per minute. You'll quickly find that non pushrod
>engines are far superior to the archaic crap that gets pushed off on the public
Are you trying to tell me that the PISTONS in an OHC setup are somehow
magically able to PHYSICALLY travel faster than the same pistons in an
OHV setup? You really are an idiot...
>USA. Pistons speeds, and valve actuation speeds increase to a point
>where the engine is capable of producing far more power more efficiently and
>cleaner (shh don't tell Bubba) than an archaic single cam and pushrods ever can
>reliably produce.
The OHC setup is a pretty old idea too you know...
>With a proper setup an 350 engine could turn well over 14,000
>rpms and still hold together.
Well... somebody better hurry and get the message to the folks down in
the Winston Cup NASCAR garages...
Rick Hendrick better FIRE Ray Everham and hire you to run the show...
I bet Jeff Gordon will win a lot of races then...
It's funny how the under-educated seem to know more than trained
professionals..
If you were spinning your motor up to 14,000 RPM to generate peak
power... you would be generating very little power between idle and
11,000 RPM... idle would be set to something rediculous like 5,000 RPM
>Skinny J...
Does that stand for "Skinny Johnson"?
You are such a dumbass.
--=Kwik Z=--
1995 Z-28 (4L60-E, T-Top)
396 LT1 Vortech motor (in the works)
Vortech V1 Strim 396 LT1 / LT4 (coming soon)
Tygress(Emily)
>Brian <"PHandlon"@worldnet...@worldnet.att.net> wrote:
>
>>This is due to the pushrods actually
>>deflecting and bouncing off the lifters and damaging the rockers.
>
>Wrong fuck-o... modern V-8 OHV engines experience valve float around
>6500 rpm because they use hydraulic roller cams (to avoid rocker
>adjustment while generating good power)...
Correct.
> at high RPM the lifters do
>not follow cam profile because the valve springs are not strong enough
>to keep up at high RPM, due to the step slope / incline of most
>hydraulic roller cams....
Incorrect. While springs may be a problem in some applications,
it doesn't significantly matter what strength spring is used <provided
it can reach a 6500 rpm level to begin with> with a hydraulic cam,
roller or otherwise. This is due to the oil chamber design of the
hydraulic lifter. At higher revs, the piston is displaced downward,
preventing the full lift and duration of the cam from reaching the
rocker. This is why the AFR hydrarev kit places the helper springs on
the lifter body itself rather than on the pushrod. This kit allows a
lighter valve spring to be used while still imparting the same overall
tension <valve spring plus helper spring> to the lifter. The lighter
valve spring places less force on the oil piston and raises the rpm
level where the lifter can operate before displacement occurs.
The steep slope of roller cams is a factor, but not the primary
one. The failure of hydraulic lifters is seen on flat tappet cams as
well at high rpm.
>>If you really
>>want to look for a redline maximum for the 350 you need to look at piston
>>speeds in terms of feet per minute. You'll quickly find that non pushrod
>>engines are far superior to the archaic crap that gets pushed off on the public
>
>Are you trying to tell me that the PISTONS in an OHC setup are somehow
>magically able to PHYSICALLY travel faster than the same pistons in an
>OHV setup? You really are an idiot...
Yep. Piston speed at an rpm is determined by crank throw and rod
length. This will be the same whether the engine is OHC or not.
>>With a proper setup an 350 engine could turn well over 14,000
>>rpms and still hold together.
Of course it could, but why would you want to?
---
'69 Camaro w/Edelbrock manifold and fancy plug wires
'85 Cutlass w/airfilter upgrades w/tricked spark plugs
There's maybe something else on those that I forgot, but
it probably doesn't matter as much. ;) Probably.
Kwi...@camaro.com
wrote:
> Incorrect. While springs may be a problem in some applications,
>it doesn't significantly matter what strength spring is used <provided
>it can reach a 6500 rpm level to begin with> with a hydraulic cam,
>roller or otherwise. This is due to the oil chamber design of the
>hydraulic lifter. At higher revs, the piston is displaced downward,
>preventing the full lift and duration of the cam from reaching the
>rocker. This is why the AFR hydrarev kit places the helper springs on
>the lifter body itself rather than on the pushrod. This kit allows a
>lighter valve spring to be used while still imparting the same overall
>tension <valve spring plus helper spring> to the lifter. The lighter
>valve spring places less force on the oil piston and raises the rpm
>level where the lifter can operate before displacement occurs.
> The steep slope of roller cams is a factor, but not the primary
>one. The failure of hydraulic lifters is seen on flat tappet cams as
>well at high rpm.
Hmm... well... Thanks for the update... I think I see what you are
saying... but I am still trying to "decode" this new information...
on a side note... the AFR Hydra-rev kit has no impact on cetain cam
profiles... for some reason... according to AFR... it doesn't do
anything for the TPIS ZZ-9 cam due to the shape of the lobes...
-== Kwik-Z ==-
396 LT1 Vortech (in the works)
Kick ass 396 LT1 being built!!!!!
Tygress(Emily)
>On Wed, 03 Feb 1999 18:37:35 GMT, Em...@Tigress.com (Tygress(Emily))
>wrote:
>
>
>Hmm... well... Thanks for the update... I think I see what you are
>saying... but I am still trying to "decode" this new information...
>
>on a side note... the AFR Hydra-rev kit has no impact on cetain cam
>profiles... for some reason... according to AFR... it doesn't do
>anything for the TPIS ZZ-9 cam due to the shape of the lobes...
Yeah, there are some oddball cams out there that it just doesn't
seem to matter with. It would really interesting to see a derivative
acceleration graph <shows the rate of acceleration> for the lifter
across that cam's nose. I'd bet a good bit it's an asymetrical curve.