Search for my old thread from last fall and you will see that I opened up my 4 barrel 389 engine. I have been looking for ways to improve it without going nuts. Several have suggested that i use the tri power cam. I see that in this month of street rodder or custom rodder that they utilized a Thumper roller cam which I know is more aggressive because it can take advantage of itself being a roller. Any opinions on this as opossed to the tri power cam?????? And they failed of co**** to give the specs on it ;/ Also, I have already port matched the heads to the intake and the exhaust to the manifolds as best as possible though I do want to go the route of headers soon. I also very very carefully removed the sharp edges from the combustion chambers. Please throw out there any ideas to improving the engine/ top end before I ****on it up, thanks
One thing I can tell you.....do your homework before buying a cam for a Pontiac. There are an awful lot of them that are Chevy tailored specs ground on a Pontiac blank, and that just doesn't work. You can do a lot worse than one of the factory performance grinds.
http://ronspontiacpage.com/reference-pages/stockheadspecs.htm Which heads do you have ? There's 2 threads on this two so I'd get one of them closed to limit confusion
oh, sorry, here's the link n thanks for the imput http://www.jalopyjournal.com/forum/showthread.php?t=741451&highlight=iron****er
What's the engine code on the right front of the block? That will help tell where we're starting. I believe the standard Bonneville motor was a 303-HP 389 with 4bbl carb and 10.0 or 10.25:1 compression.
About all that's cost-effective on that build is an aluminum intake, edelbrock 600 CFM and headers, if you can find them. Add a Pertronix module to the distributor, have it checked on a machine to verify the advance works as specified. Once you start talking cams, you're past the stopping point on the slippery slope; then it's lifters, springs, the rods are weak, cast pistons are suspect. Don't go there. jack vines
Yes, almost all bottom ends are identical though. The HP differences are in the heads and cam. The block numbers will tell you what "Pontiac" put it together as and with that you can determine what heads it's SUPPOSED to have. The head castings will tell you what compression you have in front of you. Lots can happen in 49-50 years. Takes about 4-6 hours to swap heads & No telling what's on there without looking.
MAximize the strong point of Big Blocks.....TORQUE! These Ponchos stock heads hinder deep breathing. Keep to a theme, street motor that spend most of its RPM's on the low side. Off idle to 5,000 like cam. Match components so it works as a team. APPLECRATE is a one the Poncho gurus here on HAMBtown.
This is not a knock on this site, but if you want more info on this than you know what to do with, you should check out the Performance Years website.....technical forums. The whole thing is nothing but Pontiac and there's a 62 up section. If you can't find what you're looking for there you have real problems! Just a suggestion.
9773345 1964 389 267, 283, 303, 306 hp 1.92 / 1.66 70 cc Pressed 1964 421 320 hp 1.92 / 1.66 70 cc Pressed 1964 326 280 hp 1.88 / 1.60 10:1 CR Pressed 1967 400 350 hp 2.11 / 1.77 72 cc Pressed ^the formatting didn't follow but you get the idea^
Here is an indispensible guide to Pontiac performance: http://www.amazon.com/Pontiac-Racers-High-Performance-Handbook/dp/B0006YSIDQ/ref=sr_1_1?ie=UTF8&qid=1370017602&sr=8-1&keywords=pontiac+racer%27s+%26+high+performance+handbook
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