Questions on Heads & Compression
Questions on Heads & Compression Guys I just installed a vrx4 camshaft on my 2000 trans am. (VRX4 Camshaft 228/230 .588/.592 112 LSA). I'm pretty sure I want to get the Trickflow 220 as cast heads as of right now from vengeance racing. I've learned quite a few things over the past months on internal engine work. I'm doing all the install myself in my garage. The camshaft is already in and ready to go, and my stock heads are pulled off. Excuse me for the newbie questions but what exactly does milling do? Raise your compression ratio? What would happen if I didn't do any milling at all and simply bolted the heads on right out of the box just like they come? Many people have told me to have them milled to 60cc while other told me 59cc and 61cc. Now what size head gaskets will I need?
When you mill the heads the combustion chamber becomes smaller and that raises your compression ratio. How far the piston sticks out the block along with head gasket thickness also affect your compession ratio as well. You need to check PTV clearance before you let somebody start cutting on your heads. What size head gaskets do you need is determined by PTV clearance. You want as high a compression as you can get without risk of hitting the piston.
Since your cam, and now heads, are from Vengeace Racing I would seek their advice on coordinating that cam with the decision regarding milling the heads as well as the choice of gaskets.
I ran a 230/234 111+2 with those TFS heads milled to 60.5 cc and a GM MLS gasket. On a stock bottom it left me about 11.2-1 CR which was about as high as I wanted to go.
Keep in mind those heads have the valve angle rolled back to 13.5* which helps PTV so if you keep your OEM heads I would not cut that much....
Keep in mind those heads have the valve angle rolled back to 13.5* which helps PTV so if you keep your OEM heads I would not cut that much....
I ran a 230/234 111+2 with those TFS heads milled to 60.5 cc and a GM MLS gasket. On a stock bottom it left me about 11.2-1 CR which was about as high as I wanted to go.
Keep in mind those heads have the valve angle rolled back to 13.5* which helps PTV so if you keep your OEM heads I would not cut that much....
Keep in mind those heads have the valve angle rolled back to 13.5* which helps PTV so if you keep your OEM heads I would not cut that much....
