Head Question

[73firebird]

Ok you pontiac guys on here. I have a 1973 pontiac formula 350 with the #46 heads. I dont know what the compression is on it but I do beleive the chamber size is 89cc. Here is my question. If I can get a set of #17 heads from a 1968 350 would they do anything to improve performance on my 350. The guy selling them says that they should make about 9:2.1 compression and between 260 to 320 horsepower. I already have an edelbrock performer intake, holley 650 (soon to be 670 street avenger) MSD 6a box and blaster 2 coil and a k and n air filter. I just want to basically know if the #17 heads will bolt right onto my 350 and if I would see any performance gains. Thank you for your help.

Carlo

[Drewhelm]

Yes, the 17 heads will bolt right on, however, those are a 2 barrell head. They will NOT make full use of the upgraded intake and carb. It would probably bump up compression to 9.2, but you need more than JUST compression to make more power.

Another thing to be aware of is the fact that the 17 heads will most likely NOT have screw in studs. I'd recommend looking for a set of 18 or 48's. Or you could simply have your heads milled to raise compression. The later heads you already have will do with the intake, carb, and cam upgrage with a little milling and clean up of the intake and exhaust ports. Check and I bet they even have screw in studs, if not you can have them installed when you have them milled.

[73firebird]

Hey thank you man, The car was originally a 350 2 barrel car when I bought it and I changed it from a 2 barrel to a 4 barrel after i had it for a while. I bid on the 17 heads already so i will prob have to end up buying them to save bad feedback however if they need converted to screw in studs thats cool. I was just wondering if the heads would add any performance. I plan on putitng in a slightly bigger cam here soon, something with about 214/214 at .050. Thanks for the feedback.