Buick big blocks
James W. Swonger
and bad points, as any motor does. Their greatest advantages are their
excellent torque and light weight. The biggest disadvantage to the
hot rodder is the limited availability and higher price of performance
parts. A Buick big block, even smogged, puts out over 1 lb-ft / in3.
The best factory 455s (the 1970 Stage 1s) gave 510 lb-ft or so of
torque, and at low enough RPM that they were great street motors. The
Buick motors were not typically set up to rev high, and many bracket
racers who run Buicks use relatively tall rear end ratios (around 3.8:1
vs. high 4s:1 for many other, higher revving motors).
The series started with the 400/430 motors in 1967. These engines are
identical except for the bore diameter. The stroke is 3.90" and the bores
are 4.0 and 4.1875" respectively. The 400 therefore has much thicker
cylinder walls, and in fact the block can be turned directly into a
430 by boring - this block could be bored and rebuilt 5 times at .030"
bore increment. The 455 was introduced in 1970 and has a slightly
different casting to accommodate the larger 4.3125" bore. The moving
parts are interchangeable, except for the heads, between all 3 types.
The 455 had fairly thin walls, which is a potential problem if you
try to bore to .060" over; sleeving is not unheard of. The big block
Buick weighs in at about 30lb more than a SB Chevy motor, far lighter
than the massive BB Chevy motor but very close in torque and HP in
stock trim.
Over the years big block Buick stock intake/exhaust valving was 2.00"/
1.625" although the later Stage 1 heads had larger 2.125"/1.75" valves.
The valve size is one limitation to the RPM range/peak HP, as evidenced
by the relatively equivalent horsepower ratings of the 400, 430 and 455
stock motors (325, 360, 360) at succeedingly lower RPM (5000, 5000, 4500).
The stock Buick heads up to 1970 had 10.25:1 compression ratios, and
reasonably good flow and port sizes (1" x 2" intake, 1" x 1.5" exhaust).
Unfortunately the early heads ('67-'69) used a different rocker/top oiling
scheme from the '70-up 455, limiting the possibilities for swapping.
The '67-'69 400/430s had a pressurized rocker rail and lightweight
aluminum rockers which received their lubrication from orifices on the
underside of the rail. Their pushrods were dry. The lower-revving 455
when it came out had cheaper stamped steel rockers and pushrod oiling.
One disadvantage of the Buick block is its oiling system. The pickup tube
is small and furthermore is about 1' from the oil pump, which is external,
and connected to it by a 1/2" passage in the block casting. The engine
has large main bearings and requires a good oil supply for longevity.
Most serious Buick builders enhance the oiling system as a first priority.
High pressure/high volume pumps, drilling of the pickup run and larger
pickup tubes are de rigeur, while some even go to the lengths of replumbing
some of the internal feeds to obviate other known failure modes (like the
problem of one of the lifter galleries being fed by a particularly
tortuous path which can be blocked off by cam bearing failure).
At higher horsepower levels the lightness ofthe Buick block becomes a
cause for concern as much as a weight advantage. Block girdles and grout
are used to beef up the bottom end, and enhanced main bearing cap schemes
are often employed (typically a pair of 45'd bolt holes tapped into the webs
and specially machined main bearing caps.
Although sources of Buick performance parts are limited, the places which
do supply them are extremely devoted, even bordering on religious
fanaticism, to the Buick motor and the range of parts is pretty good. For
example, one outfit offers about 20 cam grinds for the Buick 400/430/455
which range from .400" lift to about .7" - and suggest that the top end
ones should idle at about 4000RPM. Good intakes, oversize valves,
aluminum heads, forged pistons of various compression ratios and beefed
up internal components of every type are available. The catch is, everything
costs about 2X the equivalent SB Chevy item largely due to the small size
of the market.
The biggest 3 aftermarket performance suppliers are Poston, Kenne-Bell and
T/A Performance. Other large mail-order parts places stock some of the more
common items (rebuild kits, etc.) but do not seem to traffic in the more
exotic items. Poston also caters to the Buick restoration scene, while
K-B and T/A seem to be straight mechanical performance oriented.
Poston Enterprises, Star Rt. A, Box 243, Atmore, AL 36502 1-800-635-9781
T.A. Performance Products, PO Box 14615, Scottsdale, AZ 85267 (602) 867-8488
Don't have the K-B address handy; however I know they're active, esp.
with the GN turbo scene. I've bought V-6 stuff from them and had good
results.
--
##########################################################################
#Irresponsible rantings of the author alone. Any resemblance to persons #
#living or dead then yer bummin. May cause drowsiness. Alcohol may inten-#
#sify this effect. Pay no attention to the man behind the curtain. Billy!#
Robert A Walker
>with the 430, all stock. I'm a Modern Man and will not put up with fussing
>with the engine, dist., carb, etc. In order to make my engine more reliable
>and run more efficiently, I'm thinking about 1.) upgrading the 4-bbl QJet
>to a Holley 2-bbl closed-loop fuel injection (big bucks - $800?), and 2.)
>upgrading the ignition system to some sort of electronic version. I've
>looked into the various GM HEI replacements, and they don't seem all-electronic.
>You have to replace one or two thingamabobs every tune-up. Why would I want
>to go whole hog and upgrade to a semi-street/race Mallory true electronic
>ignition? Is it worth the additional cost?
>
>This car is and always will be a "cruiser". I don't give a hoot about
>top-end horsepower, just reliability.
Just my opinion, but the simpler the more reliable. And even if
something does go wrong, easy to fix.
Spencer Shafer
> Buick big blocks were produced from 1967 to 1976. They have their good
>and bad points, as any motor does. Their greatest advantages are their
>excellent torque and light weight. The biggest disadvantage to the
>hot rodder is the limited availability and higher price of performance
>parts. A Buick big block, even smogged, puts out over 1 lb-ft / in3.
>The best factory 455s (the 1970 Stage 1s) gave 510 lb-ft or so of
>torque, and at low enough RPM that they were great street motors. The
>Buick motors were not typically set up to rev high, and many bracket
>racers who run Buicks use relatively tall rear end ratios (around 3.8:1
>vs. high 4s:1 for many other, higher revving motors).
>
> The series started with the 400/430 motors in 1967. These engines are
>identical except for the bore diameter. The stroke is 3.90" and the bores
>are 4.0 and 4.1875" respectively. The 400 therefore has much thicker
>cylinder walls, and in fact the block can be turned directly into a
>430 by boring - this block could be bored and rebuilt 5 times at .030"
>bore increment. The 455 was introduced in 1970 and has a slightly
>different casting to accommodate the larger 4.3125" bore. The moving
>parts are interchangeable, except for the heads, between all 3 types.
>The 455 had fairly thin walls, which is a potential problem if you
>try to bore to .060" over; sleeving is not unheard of. The big block
>Buick weighs in at about 30lb more than a SB Chevy motor, far lighter
>than the massive BB Chevy motor but very close in torque and HP in
>stock trim.
Big question, commonly asked, I'm sure: I have a Buick Electra 225 Convertible
with the 430, all stock. I'm a Modern Man and will not put up with fussing
with the engine, dist., carb, etc. In order to make my engine more reliable
and run more efficiently, I'm thinking about 1.) upgrading the 4-bbl QJet
to a Holley 2-bbl closed-loop fuel injection (big bucks - $800?), and 2.)
upgrading the ignition system to some sort of electronic version. I've
looked into the various GM HEI replacements, and they don't seem all-electronic.
You have to replace one or two thingamabobs every tune-up. Why would I want
to go whole hog and upgrade to a semi-street/race Mallory true electronic
ignition? Is it worth the additional cost?
This car is and always will be a "cruiser". I don't give a hoot about
top-end horsepower, just reliability.
David Haile
--
/-------------------------------------------------------------------------/
/ David W. Haile - Kuo & Associates, Inc., Ft. Collins, Colorado /
/-------------------------------------------------------------------------/
gordon perry
Thanks for the info on the Buick parts suppliers. I have a great old 73
Regal with an almost perfect body but with a motor which has not been
run in almost 6 yeas. I was stored under cover here in San Jose, CA and was in
fact, given to me to get rid of it. Wonder if you have any info on warming up
the 73 California smogged 350 4b like mine. Would appreciate any info from
other 350 Buick owners.
--------------------------Gordon Perry--------------------------------------
----------------...@netcom.com---------------------------------
---------------------------73 Regal 80 Firechicken--------------------------
Jon D. Rodder
>Big question, commonly asked, I'm sure: I have a Buick Electra 225 Convertible
>with the 430, all stock. I'm a Modern Man and will not put up with fussing
>with the engine, dist., carb, etc. In order to make my engine more reliable
>and run more efficiently, I'm thinking about 1.) upgrading the 4-bbl QJet
>to a Holley 2-bbl closed-loop fuel injection (big bucks - $800?), and 2.)
>upgrading the ignition system to some sort of electronic version. I've
>looked into the various GM HEI replacements, and they don't seem all-electronic.
>You have to replace one or two thingamabobs every tune-up. Why would I want
>to go whole hog and upgrade to a semi-street/race Mallory true electronic
>ignition? Is it worth the additional cost?
>
I would reccomend going to an HEI distributor. Yes, it does have mechanical
parts that have to be replace a few times, the cap and rotor, just like
any distributor. Someday you will probably also have to replace the module,
or you can eliminate the module with an MSD-6AL and msd HEI conversion kit.
As far as the fuel system goes, I think very poorly of the Holley
projection system. The TBI unit itself isn't too bad, but their control
system doesn't impress me at all. I think there are some places that
sell kits that use the projection throttlebody with a GM computer, but
personally I don't think its worth the money. Unless you just really
want to spend $1000 or more on a new fuel system, I'd reccomend just
getting the Q-jet rebuilt by a good carb shop.
--
--=< Jon D. Rodder ----- rod...@ccwf.cc.utexas.edu >=--
\ IRC-Op at tramp.cc.utexas.edu (Rodder) /
\ 89 Jeep Wrangler - 258/PIECE OF JUNK! /
\ 79 Rx-7 - 12A/Holley 4bbl /
\________67 Camaro RS - 350/4spd________/
James W. Swonger
I believe the '75 - '76 455 engines had HEI. These would be a straight
swap. Also, I've heard that the 350 Buick HEI is interchangeable. Since
you're unlikely to exceed 6000RPM, a clean HEI setup ought to be more
than adequate. If you pull the points-type distributor, save it. They're
not too easy to find, and the ones I run across always seem to be missing
parts by the time I get there.
As far as going to FI, the open-loop Pro-Jection system has a reputation
for being a clunker. You might be better off to get a Q-jet set up by a
pro. Part of your driveability problems, if any, may stem from 10.2:1
compression.
If you have the ST-400 trans, the gizmo that switches the torque
converter pitch could have a big effect on off-the-line behavior and
idle. It's a switch mechanism mounted on the intake, driver's side rear.
You should be in high-stall at idle and WOT, low stall at part throttle.
Staying in low stall all the time will make your idle hard to live with;
permanent high-stall will keep you slipping as you cruise.
Unknown
|>
|> If you have the ST-400 trans, the gizmo that switches the torque
|> converter pitch could have a big effect on off-the-line behavior and
|> idle. It's a switch mechanism mounted on the intake, driver's side rear.
|> You should be in high-stall at idle and WOT, low stall at part throttle.
|> Staying in low stall all the time will make your idle hard to live with;
|> permanent high-stall will keep you slipping as you cruise.
|> --
Is there a converter like this for the TH350/400 tranny's? I am reluctant to
put a high stall converter in my street driven TA. The low stall speed really
kills off-the-line launch but I can pass a few gas stations.
Anyone know?
$0.02
Ericy
James W. Swonger
This transmission is an evolutionary fluke. It's sort of a bridge between
the earlier Dynaflow type, which had a continuously-variable torque
converter operated by a linkage from the throttle, and the fixed-pitch
three-speed automatics of later years. The ST400 has two stall speeds,
one low (maybe even lower than normal) and one fairly high.
The Super Turbine 400 has the same case and guts as the TH400. There is a
solenoid inside which changes the stator pitch of the torque converter.
The ST400 was produced up until about 1968 and can be found in cars like
Buick Wildcats, Electras, etc. The 1969-up models do not have them.
The advantage was that you could use a fairly "big" cam and still idle
nicely, haul that boat up to speed and then cruise as frugally as possible.
The 430s had cams with about .450 - .490 (somewhere in there; I forget
what I measured) of lift and 10.2:1 CRs, but they were in Buicks and
had to idle like it.
The transmission will be BOP-pattern. If your T/A is older, you're set.
If it's one of the newer ones, everything's Chevy-pattern, isn't it?
Your cheapest option is to find a junker '67 Buick cruise ship. If that
isn't possible, I know Poston sells the switch-pitch converters and the
solenoid/connector/instructions to convert regular TH400s to the same
mode. They also have a couple of torque converters with different speed
sets, (higher and much higher) for folks who like to drag race Buicks
and then drive them home.
Jim Wylde
I hope someone can help me here.... I'm just about out of patience and ready to take
a shotgun to my beast!
I've got a '79 Monte Carlo. It originally started out as a utility ride, but when my
ex blew the 305 in it, I decided to upgrade to a 350...
The block is a standard 350 w/ a 4-bolt main from a 79 ambulance (3/4 ton frame)
Got a set of 1.93" intake heads (originals were cracked)
Crank is good.
New cam (stock), lifters, rings, bearings..... all the normal stuff.
Quadrajet carb w/ electric choke (rebuilt by serious Rochester person)
Turbo 350 trans w/ standard torque converter.
I seem to have a vaccuum leak that is about the size of Manhatten that varies with
temperature, humidity, and the general mood of the car. It'll sometimes start.
It runs like shit till it warms up, and won't idle for more than a couple of seconds.
I've been playing with this for about 3-4 weeks now, and have gotten nowhere.
Gaskets are on correctly. Intake manif. is on correctly. Carb is mounted properly.
Intake is torqued down the right way. Got Soc. Head Cap screws (Hi-strenght steel)
Timing's right. TDC is TDC. The entire ignition system has been replaced.
Essentially, if I can get it to run, I think I've fixed it, move it up and down the
driveway just to make sure, pull it back into the garage, run it for 1/2 hour. Next
day. Same problem.
I've rebuilt umpteen Buick and Caddy big blocks (350, 455, 472, 501) and have never
run across something this stubborn. I'm hoping it's some little quirk inherent to
Chevy's that I don't know about yet (first Chevy block)
Anyone got any ideas? Or should I just load up with deer slugs?
Jim Wylde
nasi...@anhep3.anl.gov
James W. Swonger
hooked up? A carb rebuild can't always be finished on the bench. Maybe
the primary mixture needs adjusted. Try the choke/fast idle first though,
if it runs OK warm.
t...@drycas.club.cc.cmu.edu
I doubt you're saving much gas with a low stall speed converter...you sure
you aren't confusing this with having a high ratio rear end? Besides, real
hot rodders are concerned with power and speed and such, not gas mileage! :>
heh heh...:> :> :>
TED
t...@drycas.club.cc.cmu.edu
The only vacuum leak the size that you describe that I've seen was at the
carburator gasket. You might check it again. If that IS the problem you
should be able to feel around the carb base with your hands when you hear the
leak and feel it. Another thought is does it possibly have a bad egr valve?
They can do weird things like that depending on whether they are open or
closed at the time. Hope you find it!
TED
James W. Swonger
>
> I doubt you're saving much gas with a low stall speed converter...you sure
>you aren't confusing this with having a high ratio rear end? Besides, real
>hot rodders are concerned with power and speed and such, not gas mileage! :>
>heh heh...:> :> :>
>
If you're not stalled (minimal impeller/turbine relative slip) at your
cruise RPM, you'll be wasting gas and throwing heat. The torque converter
multiples torque but does it inefficiently. If you use a high-stall
converter a trans cooler is mandatory to dump the heat generated by all
that slippage (actually fluid shearing I guess).
Sean Kelley
carbuator cleaner...and two....a propane bottle with the attachment, but
do not light it, run it along all gasket lines until there is a change
in idle....
you might want to just check that everything is torqued down properly
also, like carb, intake manifold, etc...
--
________________-----------------_____________
\ /
\ SEAN KELLEY KEL...@CWIS.UNOMAHA.EDU /
------------------------------------------
nasi...@anhep3.anl.gov
>Two methods you can use to find a good leak like that...one..good old
>carbuator cleaner...and two....a propane bottle with the attachment, but
>do not light it, run it along all gasket lines until there is a change
>in idle....
>
>you might want to just check that everything is torqued down properly
>also, like carb, intake manifold, etc...
Thanx... I used carb cleaner, but I never thought of the propane trick.
I'll have to double check. But, yeah, all the bolts are torqued
properly. They have been checked, double checked, and the double
checks have been double checked.
Jim
Jim Wylde
> Sounds like things are just a bit too lean. How's the choke? Thermac
>hooked up? A carb rebuild can't always be finished on the bench. Maybe
>the primary mixture needs adjusted. Try the choke/fast idle first though,
>if it runs OK warm.
*sigh* ... Already did that. I've had the mixture screws in every
possible position from ultra lean to almost falling out. It didn't
make any difference in the problem. 'course when I got way outta
line on the mixture it REALLY ran shitty...
It's an Electric choke. I've played with having it hooked up, not hooked
up, hooked up at different electrical terminals... No change.
I also put on 2 other carbs that I knew were good. (took em off of
running engines for a while...) again. No go.
It's really frustrating.
Thanks tho'
Jim
Mike Mshar
First off, fantastic group. Thanks to those responsible for its creation.
I hope that I can help somebody on this group, as I am sure that some day
one of you will help me.
Anyway, on with the show...
You said in your article that you eliminated the carburetor. Coming from
somebody who builds Rochesters, this is good, because it eliminates a lot
of possibilities.
I have one thing you might want to check.
Check each and every one of your vacuum lines, especially the one that goes
down to the transmission. One time that line came loose on my brother`s
car, and it took me forever to find it. If you can eliminate ALL vacuum
lines as possibilities, then maybe look into the EGR valve, a bad rebuild,
or something else.
BTW the fastest way to check the vacuum line system is to disconnect each
line one at a time from the carb or intake. Once disconnected, plug the
port and see if the engine idle quality improves any. It should not take
long, and it eliminates a lot of possible sources of rough running and
idling.
I hope I get lucky and figure this out, but if not, good luck!
Ain`t cars a bitch sometimes??
Mike
--
| Michael G. Mshar | My Life-Long Goal: To keep common sense |
| mms...@mn.ecn.purdue.edu | alive and keep the idiots from taking over.|
| ms...@mentor.cc.purdue.edu | \\President, Nice Guys Anonymous// |
|____>>> United States Steel, Mechanical Engineer, Technical Services <<<____|
--
| Michael G. Mshar | My Life-Long Goal: To keep common sense |
| mms...@mn.ecn.purdue.edu | alive and keep the idiots from taking over.|
| ms...@mentor.cc.purdue.edu | \\President, Nice Guys Anonymous// |
|____>>> United States Steel, Mechanical Engineer, Technical Services <<<____|
Jim Wylde
Ready??? Yer not gonna believe it. I finally got so frickin'
disgusted with this project (mostly cuz my antique caddy doesn't
go out in the winter) so I called one of my local hot-rod shoppes.
They had a nice man with a nice tow truck come and take my @#!!#%
car away, and the next day it was fixed!
Guess.
I made two minor mistakes that added up to a major one. First,
because all my experience has been with buick and Caddys where you
don't have to adjust lifter lash, I put the rockers back on where
I got them off from ( x number of turns in...) only trick is I
put on different heads. They were a bit tooo tight and screwed the
valve timing up. No real problem, if I coulda got the motor running
long enough to remember that I had to play with it. Second, I
bought a "stock" chevy 350 cam from Crane. I figured it was "stock"
and this ain't a serious hot rod project, so I ain't gonna bother
to check the lift and duration and just put it in. Crane's idea
of a "stock" cam is one that has a LOT more lift and duration than
GM's.
Sooo, I had the rockers WAYYYYY to tight now, and my valves were
alll over the place! They were opening and closing in no relation
to what the engine needed. So, after a coupla hours of monkeying
around and replacing some push rods (owwwwwww!!!) it runs like a
top.
Well, now I know. Nobody ever said education was cheap....
Thanx for all the help everybody offered. This was a real wierd
one that I would have never found myself just from my inexperience
with Chevys.
Jim