Someone I met a year or so ago said that you can mill a 083 head to 081 compression. (64cc to 58cc i believe) I have a set of 083 heads that I P&P'd but I have no need for them as I am going with an AFP head. However, my buddy with a 87 camaro has a 305 LG4 with heddman shorties, 3" exhaust (not cat), 87 350 TPI cam with 1.6r (Hydrualic roller), Edelbrock performer intake, 600 4160 Holley carb VS, talor wires and a Acell coil. Not to mention 3.73 gears. He is dieing to take my heads but I keep telling him the compression will drop too much. What do you guys think? Even if you could, what about valve clearance?

 

I'm putting a set of 081 heads on my 355. I'm running dished piston and compression will be around 9.45 to 1. If he's running flattop pistons he will be around 10.35 to 1 and if its bored over he'll have higher compression. Valve clearance will be alright, but he needs to check clearance anyway. The difference between the two is the valve size. Just do a little research on the board or MORTEC and I think you'll have your answer.

 

I've done one massive search already and got info on this particular thing. Lots on how you shouldn't put a 083 head on a 305. BTW, he has a 305, not a 350. You will lose compression. I think it drops you to 8.5:1. I know all the differences between the two. I was hoping someone here has made an attempt. Ah well... time to check it the hard way...

 

You will definately lose power by droping your compression ratio....

He could throw on the 083's no problem, but what's it worth to mill them down to the proper compression ratio? Have you checked? If you mill lots from the head you may also have to shave the intake......