TPIs weren't set up to flow a lot of air, so without modifications a high HP / high RPM cam will not work well with it...A good low to mid range high torque cam will add some grunt...
If you're still building the engine consider stroking it with a 400 crank (kits available everywhere) It will boost your displacement to 383 with a .030 bore or 377 w/out. The longer stroke will be a multiplier of the TPI's excellent low end torque characteristics, and with a cam designed to enhance the low end torque as well, you'll have yourself a sneaky 'lil stump puller sure to surprise a lot of people off the line.
As for compression, unless you want to run race gas or buy cases of 104+ keep it to 10:1 as a maximum and make sure you hook up the oxygen sensor so the computer can mix the gas/air at the proper ratios.
My 2 cents.
68 El Camino...Slow, Much Work Required
98 Z28...Fast, No Work Required
Goodfellow AFB, San Angelo, TX -- Where? That's what I said..
Your best option is to call your favorite cam manufacturer. The tech people can tell you exactly how far you can go (with their cams) and still retain the stock chip. Speed density system will be different than a MAF system.
I am very happy with the suggestion from comp cams. E-mail me for particulars if you're interested.
Rick (Abilene Texas)
72 El Camino
Unless you change the throttle body and the runners, it doesn't matter what cam you run, it will still fall on it's face about 4750 rpm. I put the 350HO cam in an 87 IROC and it slowed it down. This was with headers and a chip. It killed the low end wheelspin, but it wouldn't pull past 5000 rpm. You could still feel the car fall off at 47-4800rpm.
The runners and throttle body limit the amout of air the motor can pull through the intake system.
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