Since going to Vegas in October with Skip's 68 GS "race car" I've been rolling ideas around in my head to make this thing significantly faster... Here is what we have in the engine: 455 bored .040" over (464") Ported Stage1 heads (by Steve Bronston) unkown flow #'s TA 212 cam TA pistons, unkown compression, possibly 9.5:1 or higher (with these heads) Edelbrock performer intake - untouched Edelbrock 1910 carb - 850 cfm q-jet Poston 1 7/8 headers, 2.5" exhaust to Hooker mufflers, nothing after that Car ran 13.12 @ 102 at vegas with a 1.9x 60' time. That was with an ST400 w/ an st300 convertor (??) and a 12bolt w/ 4.11 gears and 275/60/15 Quicktimes At carlsbad raceway (pretty much sea level) it ran 13.22 @ 106 with same setup as above but with 225/70/15 BFG comp t/a radials (2.7+ 60') This year it ran a 13.10 at vegas @ 101 with a TH2004r w/ stock? GN lockup convertor, same rear, and M/T Drag Slicks 29.5x9x15 I know this car should be able to run a 12.8 at sea level with some traction but I think the convertor in the new tranny is holding it back, the best 60' with this trans was in the 1.9's while the Th400 was 1.80... Back to the engine... I know the heads we have are pretty serious and they are the whole reason this car runs as good as it does. My thoughts are that we can pick up several tenths by swapping out the cam for something much more aggressive. I really like the 212, it is an excellent street cam, but this is not going to be a street car forever. What I am thinking is to go with a much larger cam with a lot more duration. I would like to put roller rockers in as well. I also think an SPX or SP-1 intake would be in order along with 2" primary headers and 3" exhaust... I do not have a specific cam in mind yet, looking for suggestions here... I will also be investigating replacing the 2004r with another TH400 (BUILT) with a good high stall convertor (10" ?) The rear end and gears I'll leave alone as it is a well built setup, unless something in the engine changes that warrants a big gear change. I also plan on doing some rear suspension mods (all is stock other than a factory sway bar, boxed lower arms, and traction bars - the ones that relocate upper control arms on axle), We have a set of adjustable upper control arms (hotchkis) that we will put in, I may also change rear springs and add air bags. The goal for now is to get very low 12's, possibly high 11's while not having to run the engine super lean or at super high rpm's. Thanks for any advice to come Dan
I can't offer any specific advice, but if you're looking for a new cam then you're going to want to know the compression. Either do some research and see if you can't get all the numbers and calculate the C.R. or just do a compression check and find the cranking compression. That way at least you'll have some numbers to give your cam guy.
I'm running Poston's 113A cam, which is very similar to T/A's 413 cam, with an SP1 intake and Holley 950HP carb. With a 3.73 rear and th400 I've run a best so far of 11.86 at 112 mph on 26" slicks. And my car weighs 4050 lbs., stripped of everything including the a/c system and spare tire. Compression is 10 to 1 with 67 430 heads w/Stage 1 valves. I am actually considering selling my pro-built TH400 and 9.5" 3200 stall converter and possibly going for a killer 200R4. PM me and we'll talk. 4.11 gears and a TH400 would put you through the traps at 6690 rpms if you had enough engine to run a 11.66 at 117 mph! So you're probably fine there. Air flow is a big one with Buicks, and that means heads. If your heads are flowing enough, the SP1 may be a good upgrade along with a cam with a bit more duration.
I switched from a 3000 sp to a 4000 s/p, and my 60 ft dropped from 1.85 to 1.70. if you go to a bigger cam you will deffertly need a 4000 s/p. there are 11 second cars, that run just airbags and boxed lowers. i would work on your 60 ft times first, cars that 60 ft well ussually run good 1/4 times
with ported heads and a 4.11 rear that cam isnt the best choice. you need something like the ta413. hell even the ta113 would be better than the 212
First and foremost, was the car hooking up with any of those setups - are you able to leave HARD and not spin ??? More power without traction is going to make matters worse not better.....and alot more inconsistant too from run to run. I would think with those gears in the rear your short time should be at least a tenth or 2 faster....which should be double that on the big end. Your mph shows your making good power.
I've been trying to respond to this post but every time I sit down I get called away!!!! Ok, The heads flow great, they were professionally done by Steve Bronston (BPE?) for a fellow club member who is a hardcore racer... I do not know the flow specs on the head but I imagine they are up there, probably not 300's but probably around 280+ on the intake side... I have been playing around with desktop dyno and looking into different cams, I'm kinda liking the TA 510 right now, I cam up with a fairly simple combo for over 550hp (at least on DD2000) using the 510, single plane, 1000cfm carb, same heads, 10:1 compression, and big headers... Traction is pretty good, It was in the 1.80's with the TH400, it dropped to 1.9 with the 2004r but I think that is due to not having the right convertor... We are already looking into rebuilding one of the 3 TH400's lying around the shop. I'm really happy with the 212 from a street point of view, I couldn't ask for anything better, gangs of torque and plenty of hp, however, its getting time to evolve this car way more towards race than street. Thanks for all the input! Dan Coastal Classics Corp www.coastalclassicscorp.com
