View Full Version : buick 300 performance build



67GTOGUY
01-23-2010, 10:34 PM
i have a 66 skyark with the 300 v-8 and a st-300 trans, i am in mid restoration and i believe my engine is finally on its last leg. i was thinking about a big block performance build but i think due to money constraints and for the sake of origonality i woud rather just buid the 300. honestly i am a pontiac man and i know little about buick engines, does anyone know anything about the performance potential of this engine? and if so what parts are recommended? thankyou for your time

wkillgs
01-24-2010, 11:54 AM
There isn't a lot of aftermarket support for these. Even a 4 bbl intake is hard to find.... it was only made in 1965.
For a nice build, just do the old hot-rod stuff.... mild port on the heads, recurved distributor advance, dual exhaust.
Crower offers a nice selection of cams, as does Accelerated Motion:
http://www.crower.com/
http://www.amotion.com/amcams.html#14821

TA Performance currently has Rover style aluminum heads in the works for the 300-340. They'll be pricey!

skylark64
01-24-2010, 07:44 PM
There really aren't a lot of choices for the 300 but it is a great little motor. I have one in my 64 Skylark and I've made some little improvements. Early 300s like mine came with aluminum heads and intake. I upgraded to a 4 barrel intake with a Carter AFB carb, level 2 Crower cam, and performance ignition.

You could also bump the compression with some flat top pistons. The original Power Pack 300 had 11:1. Mine is running somewhere over 9.5:1 according to the books I've got. The aluminum heads dissipate heat better so theoretically you shouldn't have any problems with predetonation. I've always run regular gas in mine and never had problems.

Of course, I am telling you all this with a 455 Buick in my garage ready to put in. There is no substitute for cubic inches. There are also a lot more performance parts out there for a 455 Buick.

For a mild street application, the 300 is a great motor. But if you're looking for more than that, I recommend going big.

67GTOGUY
01-29-2010, 11:22 AM
i have heard people say that 340 parts are interchangeable is that true?

DynoDave
03-07-2010, 11:15 AM
It is possible to put a 340/350 crankshaft into a 300 block. This combo has several advantages over a 340 based motor. The 340 is very
wide (@10.2 inches, it has a taller deck than a big block chevy and about same height as a 400/455 Buick), and many people who are not familiar with Buicks (most) mistake it for a big block. The reason Buick engines have such tall decks is that their engineers never adopted slipper-skirt pistons on any of their engines. Non slipper-skirt pistons require much longer connecting rods combined with taller decks to allow the pistons to clear the counter weights at the bottom of the stroke. By using a slipper skirt piston and a 300 connecting rod, their is enough room in the 300 block to install a modified (mains reduced to 300 main size) 3.85 stroke 340/350 crank. With a over bore of .050 you end up with 349 c.i..
For people who worry about rod length to stroke ratio, this combo yields a 1.55:1 ratio which is better that 454 chevy and several popular Ford and Chevy stroker motors.
If this combo becomes popular, 300 blocks will be more valuable.
I am currentely building such a motor and will keep you up-dated.

Bob Gibbs
03-07-2010, 06:57 PM
pay close attention to the rod bolts and cam lobes as there will be minimal clearance with the 340-350 crank in a 300 block. curious as to what you did with the different main journal size of the 340-350 crank vs the smaller 300 main journals. Bob

bob k. mando
03-08-2010, 08:54 PM
Even a 4 bbl intake is hard to find.... it was only made in 1965.


not quite true. the 1965 intakes were cast iron, the 1964 intakes and heads were aluminum.

there was an alum 4v intake available in 1964. if you get an alum intake, try to get the alum heads with it as the runners in the cast iron heads won't line up properly.



i have heard people say that 340 parts are interchangeable is that true?

some parts, yes. not the intake though, the 340 has a much taller deck and a much wider intake.

some parts can also be stolen from the Buick 231 v6.

something you'll probably find much stranger, there are a lot of parts that you can steal from Rover v8s, although you can't use their intakes either. the Buick/Olds/Rover 215ci is a shorter deck than the 300.
http://www.aluminumv8.com/tech/tech.htm



I am currentely building such a motor and will keep you up-dated.

this combo has already been built by D&D Fabrications. see the link above.

DynoDave
03-08-2010, 11:30 PM
pay close attention to the rod bolts and cam lobes as there will be minimal clearance with the 340-350 crank in a 300 block. curious as to what you did with the different main journal size of the 340-350 crank vs the smaller 300 main journals. Bob

Bob, you probably have experience or know about having to grind connecting rod bolts to clear the cam on a 383 small block Chevy stroker combo when using stock 5.7 in. Chevy rods. The same is true for the 300
Buick stroker when installing the 340/350 crank. The bolt head on the side of the rod closest to the cam must be ground and, if done properly, the integrity of the bolt is maintained. It is advisable to only do this with aftermarket rod bolts such as ARP. The mains must be ground down from the 3 in. 340/350 size to 2.50 in. standard 300 dia. At first glance, this seems like a lot to remove but the machinist will be able to grind a larger than stock radius into the crank cheek which gives the crank more strength. The rear main seal journal must also be reduced. At 2.5 in., you still have a larger main than a 350 Chevy ( 2.45 in. ). This reduces bearing speed significantly, which reduces friction, and also lightens the crank.

DynoDave
03-08-2010, 11:51 PM
Even a 4 bbl intake is hard to find.... it was only made in 1965.


not quite true. the 1965 intakes were cast iron, the 1964 intakes and heads were aluminum.

there was an alum 4v intake available in 1964. if you get an alum intake, try to get the alum heads with it as the runners in the cast iron heads won't line up properly.



i have heard people say that 340 parts are interchangeable is that true?

some parts, yes. not the intake though, the 340 has a much taller deck and a much wider intake.

some parts can also be stolen from the Buick 231 v6.

something you'll probably find much stranger, there are a lot of parts that you can steal from Rover v8s, although you can't use their intakes either. the Buick/Olds/Rover 215ci is a shorter deck than the 300.
http://www.aluminumv8.com/tech/tech.htm



I am currentely building such a motor and will keep you up-dated.

this combo has already been built by D&D Fabrications. see the link above.

I looked on their site and only see 215 stroker stuff. The largest combo I see is a 3.7 bore and a 3.4 ( stock 300 ) stroke. My motor uses a 300 block with a .050 over bore (3.8 in. ) and a 340/350 3.85 stroke. I am sure I am not the first to try this, but I never see anyone discuss it on any of the Buick web sites. I am also making major changes to the valve train to eliminate the weak Buick rocker arms. Because the stock 300/340 head has such poor flow numbers, especially considering it will have to feed 349 c.i., the head has received major porting with the aid of a flow-bench. This motor will be run on a dyno in one to two months. I will keep you posted.

bob k. mando
03-09-2010, 02:56 PM
I looked on their site and only see 215 stroker stuff.


yeah, i know. that was a one off project for them and it's been a couple of years. i was just pointing it out if you maybe wanted to give him a call and see if he'd let you pick his brain a little bit.

their more typical stroking work is putting 300ci cranks into the 3.5L - 4.6L Rovers. being as they are Buick/Rover 215 specialists.




the head has received major porting with the aid of a flow-bench.

you are aware that 215/300/340/Rover-style alum heads are next up in TA's development timeline, right?

DynoDave
03-10-2010, 11:49 PM
It's only been recently that I became aware of TA Buick/Rover head. I have never flowed an alum. Buick or Rover head, but have spent a lot of time on the flow-bench with the cast iron 300/340 head. I know that the intake in both the Rover and the alum. 300 head have smaller intake ports and valves than the cast iron 300/340 head, so there is little doubt that they flow less. As you probably know, the 300/340 head has a 1.81 intake valve and 1.37 ( same as 64 alum. 300) exhaust valve and, I can assure you, TA will need to spread the valve centers inorder to run bigger valves.
When Buick change over to the cast iron head they put in the biggest intake they could fit, obviously to acomodate the extra cu.in. of the 340 ( although this same head was used on the 300 ). Even with the larger intake, the 300/340 iron head is still a weak suck and flows about the same as a 289 Ford ( another weak suck ). The exhaust is even weaker than the 289 Ford, and is one of the weakest I have ever seen. No doubt the TA head will been very expensive, so if it dosn't flow better than 200 cfm on the intake and at least 140 cfm on the exhaust, it won't be worth the money.

DynoDave
03-11-2010, 12:30 AM
I looked on their site and only see 215 stroker stuff.


yeah, i know. that was a one off project for them and it's been a couple of years. i was just pointing it out if you maybe wanted to give him a call and see if he'd let you pick his brain a little bit.

their more typical stroking work is putting 300ci cranks into the 3.5L - 4.6L Rovers. being as they are Buick/Rover 215 specialists.




the head has received major porting with the aid of a flow-bench.

you are aware that 215/300/340/Rover-style alum heads are next up in TA's development timeline, right?

It's only been recently that I learned about the TA head. I have never flowed an alum. 300 Buick or a Rover head but have spent a lot of time on the flow bench with the cast iron 300/340 head. I know that both the alum. 300 Buick and Rover head have a smaller intake valve and port than the 300/340 iron head, so there is little doubt that they flow less. Regardless, the iron 300/340 head is a weak suck and flows about the same as a 289 Ford ( another weak suck ). As you probably know, the iron head has 1.81 intake valves and 1.37 exhaust valves. TA will have to spread the valve centers inorder to run larger valves because when Buick change over to the iron head they put in the biggest intake they could fit, no doubt to acomodate the bigger 340 ( although the same head was also used on the 300 ). The TA head will likely be expensive, but if it dosn't flow more than 200 cfm on the intake and a least 140 on the exhaust, it will be over priced.

kljr99
03-11-2010, 06:48 AM
hi i have a 67 rag top I just bought it a few months ago. I have done a lot of research i think the most power your going to get is maybe 300hp using the stock 11:1 pistons and a radical cam, and a 650 holly.
I have been thinking about using a turbo or 2 hoping to get near 400hp.
these little motors have strong lowerends if you fix some oilling issues.
theres a book building buick performance engines that goes into depth on the oil mods. buick was the first one to use turbos on the 215 but dropped the ball. Olds took the plans and built the jetfire turbo in like 62. they tried to run 10:5 to 1 and cool it with an over engineered washer fulid injection system. I think that if buick had worked out the bugs then the 300 would have lasted into the 70's\80's 1987 gnx 300 turbo has a nice ring to it. well i have to dream for a while more plenty of body and resto work before I need to build the motor

65specialconvert
03-11-2010, 09:51 AM
I had Greg Gessler do a mild port job on a set of 340 heads for my '65 Special w/stock size valves.

Valve lift .100" .200" .300" .400" .500" .550"
Intake @ 28CFM 64 117 159 187 187 189
Exhaust @ 28CFM 50 82 96 109 133 115

Intake to exhaust ratio 78% 70% 60% 58% 60% 61%

Not fire breathing results but with ported & port matched manifolds/heads it should be a fun motor with a 200R4 behind it.:bana:Cant find my cam specs,i'll add them when i do.Note i'm using 300 rocker covers for the stealth factory 300 look:bgrin:

bob k. mando
03-11-2010, 03:19 PM
but if it dosn't flow more than 200 cfm on the intake and a least 140 on the exhaust, it will be over priced.


last i heard, TA was adapting their Buick v6 ports and chambers to the Rover style head.

and given that the Stage 2 v6 chamber used to be the hot tip on the Buick design SBC head....

i would link you to the hosted article but it looks like we've picked up a typo in the php programming. :clonk:
http://www.teambuick.com/reference/library/hybrid_head.php
Parse error: syntax error, unexpected '<' in /home/teambuic/public_html/reference/library/hybrid_head.php on line 200

i suspect a missing "k" in /teambuic/

DynoDave
03-11-2010, 11:17 PM
hi i have a 67 rag top I just bought it a few months ago. I have done a lot of research i think the most power your going to get is maybe 300hp using the stock 11:1 pistons and a radical cam, and a 650 holly.
I have been thinking about using a turbo or 2 hoping to get near 400hp.
these little motors have strong lowerends if you fix some oilling issues.
theres a book building buick performance engines that goes into depth on the oil mods. buick was the first one to use turbos on the 215 but dropped the ball. Olds took the plans and built the jetfire turbo in like 62. they tried to run 10:5 to 1 and cool it with an over engineered washer fulid injection system. I think that if buick had worked out the bugs then the 300 would have lasted into the 70's\80's 1987 gnx 300 turbo has a nice ring to it. well i have to dream for a while more plenty of body and resto work before I need to build the motor

Your in the ball park with your horsepower estimate but I won't need to run a big cam to get the number.
Based on the flow numbers I have been able to get the head up to, plenty of compression, and the extra 49 c.i., I expect to make about 300 H.P. with a cam that only has 214 deg. @.050 on the intake on 112 deg. lobe centers.
This is a long stroke motor with a relatively small bore and not-to-steller head ( although it has been improved significantly over stock ). This motor is not a good candidate for high horsepower, so I am focusing on it's strength, good low and mid range torque production.
It should peak at around 4800 to 4900 rpm (which is why it will only make around 300 h.p.), but I expect it to make 350 to 375 lb.ft. of torque at a low rpm.
I am not using Buick pistons, the 300/340 piston has too much compression height ( 1.81 in.)to work in a 300 stroker combo and because it is a fully skirted piston it will not clear the counter weight at the bottom of the stroke. This one is also going into a very nice 67 hardtop Skylark.

DynoDave
03-16-2010, 10:54 PM
I had Greg Gessler do a mild port job on a set of 340 heads for my '65 Special w/stock size valves.

Valve lift .100" .200" .300" .400" .500" .550"
Intake @ 28CFM 64 117 159 187 187 189
Exhaust @ 28CFM 50 82 96 109 133 115

Intake to exhaust ratio 78% 70% 60% 58% 60% 61%

Not fire breathing results but with ported & port matched manifolds/heads it should be a fun motor with a 200R4 behind it.:bana:Cant find my cam specs,i'll add them when i do.Note i'm using 300 rocker covers for the stealth factory 300 look:bgrin:

Some observations: First a little clarifacation, @28CFM is actually
@28" of water. This is the Flow Bench test pressure most often used today when testing intake and exhaust ports. The 64 117 159 187...is the
actual flow in cubic feet/min.
Inorder to know how much you have gained in air flow from porting a given head, you first need to accurately establish a base line on the unmodified head. The stock 300/340 iron head with stock valves flows:
Lift: .100 .200 .300 .400 .450 .500
intake CFM @28" 54 112 153 172 175 175
exhaust 38 75 99 102 104 104

The gains on your head are modest but they are gains none the less.
I can tell you for sure, this head has a lot more in it and requires extensive porting and better valves to reach it's full potential, which is still nothing to write home about when compaired to what is available for Chevy,Ford and Mopar guys today.
Most engine builders today will tell you that the intake is more important than the exhaust and an exhaust to intake ratio of 65 to 70% is sufficent
(modern Pro-Stock heads are about 65%). Anytime you see a head that is 80% and above, it really means that the intake is too weak.
Good luck on your project.

Bob Gibbs
03-20-2010, 06:24 PM
my plans for the 300 engine in my special include the following,

Eagle rods CRS6000S3D 4340 FORGED H-BEAMROD 6.000'' (small journal 327)
buick forged 3.8 turbo pistons
TA heads and the new 215 intake with custom spacers
Rover roller cam
Sanderson shorty headers

the 300 has a very short stroke and with the right heads and intake will rev like a chevrolet 283 or 327, add a turbo or centrifugal supercharger and you have mighty mouse on steroids

DynoDave
03-27-2010, 11:58 AM
my plans for the 300 engine in my special include the following,

Eagle rods CRS6000S3D 4340 FORGED H-BEAMROD 6.000'' (small journal 327)
buick forged 3.8 turbo pistons
TA heads and the new 215 intake with custom spacers
Rover roller cam
Sanderson shorty headers

the 300 has a very short stroke and with the right heads and intake will rev like a chevrolet 283 or 327, add a turbo or centrifugal supercharger and you have mighty mouse on steroids

When compaired to other domestic push-rod V8's of similar displacement, the Buick 300 has a small bore and a long stroke. Example: Chevy- 283, 3.875x3.00 in. 302, 4.00x3.00 327 4.00x3.25 Ford - 289 4.00x2.87 302 (5.0),4.00x3.00. As I mention before, TA will for sure have to spread the valve centers on their new head inorder to fit bigger valves than what comes stock on the iron 300/340 head. They will likely convert to a Chevy style stud mounted rocker system to accommodate the relocated valve centers and also because the stock Buick valve train has issues even with the stock cam and weak valve springs. By the time you buy the heads and the related valve train it will be expensive.
Even with relocating the valve centers, they will not be able to put in anywhere near as big of valves as the above mention Chevy and Ford engines because of the small bore of the 300/340/350 Buick engines. When Buick intorduced the 350 in '68, the engineers knew that they had a deficient cylinder head and that it was limited in valve size because the valve center demensions of the 300/340 heads are the same as the little 215. So, they designed a new head to accommdate larger valves and bigger ports. Still, the valve size of a Buick 350,1.88x1.55, is small when compaired to Chevy,Ford,Mopar, and AMC V-8's of similar displacement.
With a 3.8 bore there is enough room to put in a bigger than the 350 1.88 intake valve, but because the small bore shrouds the larger valves, the full benifits of larger valves will not be relized.
When it comes to making big horsepower the bigger the bore the greater the horsepower potential, especially with parallel arranged/two valve heads. This is evidenced by the fact the NASCAR Cup motors, limited to 358 c.i., feature large 4.200 bores and NHRA Pro Stock 500 in. motors have nearly a 4.700 in bore!
Making big horsepower, in relation to the displacement, with a normally asperated engine requires good breathing and spinning the motor to very high RPM. Besides needing good parts in the lower-end, you need a very good oiling system, which the Chevy/Ford/and Mopar small blocks have but unfortunately is another weak point of the Buick.

Bob Gibbs
03-27-2010, 05:22 PM
There has already been one ported iron head stock intake procharged buick 350 that made over 1000 hp. it had a lot of special parts. my 500 hp project is easily feasable. the oiling system is nowhere near as big an issue on the 300 as it is the 455 because of the smaller bearing dimensions and lower bearing speed. plus i can use a rover front cover with integrated crank driven oil pump similar to what the late model 3.8 used.

kljr99
03-28-2010, 06:40 AM
I wrote about useing a turbo on my 300 and I found this guys car on a turbo regal site. he has a 350 in this. If I decide to swap motors I will go big like a 400 or a nailhead. I think the old style fits my car better even though buick used the newer motors in 67. heres the pics.
1095

1096
64 Buick special 350 turbo project

Retired mechanic John Law wanted something out of the ordinary for his ride. His 1964 Buick Skylark sports a Buick 350 with a turbo Garret turbocharger pirated off an international school bus. John hand fabricated the induction system and runs a tame 6 lbs of boost through the primaries only for cruising. But with the flip of a switch he can activate the boost operated secondaries and bring the boost limit up to 12 lbs. The car runs on pump gas with the aid of a boost operated alcohol/water injection system. John is running the PTS extreme 2004r with a 10" extreme billet converter. E.T.'s to come summer of 2005

Bob Gibbs
03-29-2010, 08:48 PM
something to keep in mind is that the Buick 300 is the same engine as a 3.8 V 6 but with 2 extra cylinders. same stroke, same deck height and same bore( if you bore it .050) the TA heads are an improved version of the stage 2 V6 head and will flow nearly 300 cfm on the intake side at 28" with the right porting. I highly doubt TA would make a head that uses chevy style rockers. the head is supposed to be a bolt on for rovers and Buick 300-340. i have zero doubt that 8#'s of boost to a 300 with the right internals and heads would surprise most everybody

exfarmer
04-07-2010, 10:16 AM
Burton Machine makes both single & twin turbo kits for SBBs.

http://www.v8buick.com/forumdisplay.php?f=154

DynoDave
04-14-2010, 11:42 PM
There has already been one ported iron head stock intake procharged buick 350 that made over 1000 hp. it had a lot of special parts. my 500 hp project is easily feasable. the oiling system is nowhere near as big an issue on the 300 as it is the 455 because of the smaller bearing dimensions and lower bearing speed. plus i can use a rover front cover with integrated crank driven oil pump similar to what the late model 3.8 used.

With a power-adder such as a supercharger or turbocharger, ( nitrous oxide if you don't mind hurting parts) it wouldn't surprise me if someone made 1000 h.p. with a 350. But how much boost did it take? I will wager it was over 20 psi. Running boost levels high enough to make that kind of power will definately require race (very expensive) gas and some serious parts in the lower end. This kind of output will require a 4340 chromoly steel crank. Since no one makes a 4340 forged crank for the 350 or possible any Buick V8 engine for that matter, it would require a custom one to be machined out of a solid billet ( Get out your wallet ). Then there is the stock engine block issue. Most professional engine builders agree that 600 h.p. is about the limit for most stock blocks (with a few exceptions), especially if you beat on it hard (race). A 1000 h.p. is a ticking time bomb.
In your case I am sure you could make 500 h.p. with a 300, but not normally aspirated with Buick heads. There just isn't enough cylinder head even with a big solid roller cam. If you use a supercharger or
turbocharger with enough boost, I am sure it could be done with modified 300 cast iron heads. The stock block and crank ( not rods) are probably up to it, but it still may require race gas and a fairly large cam (not really streetable). If you run the Rover cover with the intergal oil pump, don't you also have to use the Rover crank? What about compatibilty issues with the 300 block ect.

All along I have been talking about a normally asperated, very streetable 300 that will look stock, with the exception of Sanderson headers and an Edelbrock carb., but run as good as maybe a 400. How cool is that? This is a motor that will not use exotic (expensive) parts and one that most members of this site could afford and be proud of.

DynoDave
04-15-2010, 12:47 AM
something to keep in mind is that the Buick 300 is the same engine as a 3.8 V 6 but with 2 extra cylinders. same stroke, same deck height and same bore( if you bore it .050) the TA heads are an improved version of the stage 2 V6 head and will flow nearly 300 cfm on the intake side at 28" with the right porting. I highly doubt TA would make a head that uses chevy style rockers. the head is supposed to be a bolt on for rovers and Buick 300-340. i have zero doubt that 8#'s of boost to a 300 with the right internals and heads would surprise most everybody

The best small block Chevy and Ford heads, AFR, Brodix,Twisted Wedge, ect. flow about 330 to 340 CFM @ 28" with big 2.125 intake valves in large 4.125 plus bores. TA will not be able to run much larger than a 2" valve and even then it will require cylinder notching in the small 3.8 bore. Big valves don't work well in a small bore because of excess shrouding. If TA claims close to 300 CFM, will that be with a proper 3.8 cylinder fixture on the flow bench or will they use a 4.0 or larger fixture? Using Chevy style rockers and stiffer and lighter tubular push rods instead of the crappy Buick rockers and the wimpy and flexable .250" dia. solid push rods would be a smart up-grade, which is exactly what Edelbrock did with their 400/455 heads.

sean buick 76
01-02-2011, 10:27 AM
Mark has made a SBC roller rocker conversion and even has a studd girdle for those who want to push it really hard:

http://www.v8buick.com/showthread.php?t=200499


Here is a mild 350 that makes good street power:
http://www.v8buick.com/showthread.php?t=149569