Originally Posted by kevinr839
As far as getting 12.1 by just milling your heads, it won't happen. You would need to add domed pistons. You could run pump gas with 12.1 but you would need to retard your timing to prevent spark kknock. I would suggest buying a set of sportsman II's or soemthing. they flow better stock than most gm factory heads that have been worked on. And they are relatively cheap. Ypu can run vortec heads but you have to bu a different intake manifold due to the fact that the vortec heads only have 4 intake bolts per side opposed to the normal 6 per side. Put a 3.73 or 4.10 gear in the car and you will really see a differnce in power.
Thanks for that. So your saying sportsman II heads will work on the edlebrock intake I have on the car now?
And I was thinking of changeing the gear but the car is already at 2300 RPMS at 50mph in fourth gear!! I drive this car on the street alot.