Hey everyone i currently own a 1968 Buick GS-California with a 350 engine bored .30 over. Its tough getting alot of power out of these engines...im just curious if anyone knows any tricks to unleash some power from this engine. I think the reason its tough to unleash the power is because you cannot find that many aftermarket parts for it, boy some aluminum heads for the 350 would be nice....thanks Lardo 68 buick GS-California 350
Here are some (all that I can think of) of the not so secret secrets that make the car go as fast as it does. Camshaft, running an old Lunati one but have since gotten a new one from Bullet Cams in TN. It has the stock .392 int., .408 exh. lift. The secret is in the duration!! This cam looks alot like a roller cam. A real wide lobe. The piston rings are a real low tension set-up. They are from Tri-City rings out in California from Greg Luneak. Ring gaps are .018 1st and 2nd ring. Intake valves are the "Pro-Flow" or some type like that where they neck down near the bottom of the valve. I got them from TA Performance in Phoenix. They are big into Buick stuff. Mallory ingition with a new Mallory distributor. "Stock" as far as NHRA sees it calls for our engine to have the pistons .010 minimum down in the bore at TDC. We paid careful attention to this and made each one .011 in the hole by adjusting the stock connecting rod, length. Our NHRA approved head gasket calls for it to be .041 min. thickness which is what the blue Fel-Pro is. We also use NAPA Victors gaskets. Our bore is .030 oversized. We are allowed to go .070 over, but Buick cylinder walls are rather thin. We may try to sneak up on .060 over, but that will be later. There are places in the walls that are less than one hundred thousandths thick. Our crankshaft is stroked .013 with .015 being the max. Thats what got the pistons up in the hole necesitating the rod work. Use rubber seals for the front and rear main. We paid careful attention to the carb making sure everthing opened fully. We have many metering rods and primary jets to tune it for conditions. Pistons are off the shelf Venolia products which require a .072 deep dish that has a volumn of 17.3 cc's. A little stiffer valve springs to hold onto the bumpy duration. I haven't measured the duration. The cam has 106' lobe seperation and the cam is installed at 108' intake centerline. Our piston to valve clearance is REAL TIGHT!! About .045 where .070 is recommended, but we "only" spin the thing to about 6400 rpm. That's about it for the engine. Sorry I jumped around with things. You can get a higher lift cam that will make up for getting one with less duration, but we have to stick to the stock cam lift. The tranny is a T350 that has been thoroughly gone over by Frank Lupo's Dynamic Trans with lightened drums hubs etc. to make it easier to rotate. The converter is a 4800 rpm stall unit from Dynamic unit also. We leave the line at anywhere from 2800-3300 depending on the track and how the car is performing. This is our adjustment to get good lights. A 4.56 Richmond gear ratio rear that has a Strange spool and Mose axles with 9x30 M/T radial slicks transfer to "power". That's about it...... Car weighs 3620 with driver. NHRA minimum is 3605 in our class. We removed heater, wipers etc. in order to lighten it up. It has a 6 point roll bar and frame connectors. A 5 gallon fuel cell and Mallory pump and regulator account for our fuel needs. Anymore questions, don't hesitate to ask. Machine work was done by B&B Atuomotive Machine in NY. Nice guys! Much of this was taken from an old message. New stuff includes B&B doing another engine which is the fast one. The pistons are further "in the hole" on this one whereas the old engine had the valves sunk in the heads to allow for the big (270ish) duration. We now have solid rocker shafts after breaking 2 stock units. We also use the larger diameter adjustable pushrods which we got NHRA approval. Thanks Folks!!! Lee is currently in Joliet, IL for the Car Quest Auto Parts Nat'l event. Stop by and say HI. He should have some TA Performance catalogs if anyone needs them as they have been helping us out lately. Please support them if you can and tell'm we sent ya... OK, sounding toooo much like a commercial.. gotta go Safe Trips ALL!!! __________________ Isaac Zane # 16 NHRA J/SA 1973 Buick Apollo 350 11.48 @ 114.20 11.63 in K/SA!! hope that helps john
350-surprise!! Up until Monday night I would have agreed with you. I've been struggling with exactly the same issue. I've got a '68 GS350. I struggled with the original setup until it got too old to live with. I had a new engine built, but to the wrong specs, since my wife was using the GS as a daily driver. The ST300 trans just didn't work. I picked up a used '70 350 with a TH350. I installed it with headers and a mild convertor...ho-hum. I stuck in a Pertronix...hmmmm. Flowmasters and a 2-1/2" pipes, no big deal. Seems it had a flat cam. So, in went a Comp cam and Wahoo! ...sorta reminds me of the first time I rode in a GTO.....now, I gotta get that Quadrajet finished. These engines have to breathe, that and compression, plus at least three gears and it can really come to life. Finally-badass.:shock:
350 engine a good torque cam ,right timing curve,a ta intake,2.5 exhaust ,i changes from stock q-jet to a 600 holley and it was a noticable difference.that was with a ta rv112 cam. there is a tread here that they might be working on a set of alum heads and single plane intake. sometime in 2004. :beer andy
That's the secret secret...270 ish probably @ .050 too. My roller is 247/255 @ .050 & I thought that was heavy duration.
Big duration, low lift and 106 lsa 247/255, at 265 it is totally radical like the 510 cam, I can't wait to hear this new cam I bought but this time it will be 248/258 duration @.050 and a 528/552 lift 108lsa but they Only spin the engine to 6400, hmmmm back then in 2003 I like the 4000+ convertor, you will launch then! no more 2.0 60fts.
stock class is limited to what lies manf sent to nhra. stock lift dims are limited, but duration is whatever. stg1' used to use olds durations. but i was get a new street cam, i would have it made to 70 stg1 lift numbers and see what they are using for duration. but all the other parts need to be addressed. no stock conv's, s/p intake(stock heads would work ok), gears would be at 3.73 or bigger, suspension work AND 2'' headers. can you imagine 2'' headers on a 350? i can and had bigger ones.
Small bore, and tall ports with low lift, big duration, air sucks in faster and is left open for a long time. Maybe we should try it, where are our testers at? Maybe this 350 does not need a big lift but a boatload of duration. You know, like a Hemi Killer cam but for the 350 lol.
i was going to get a stg1 350 cam, but the twin v6 altered and other projects(cost money) changed direction. so where are all those 350er's ????
