piston to valve clearance

[eastwoodad]

do any of you guys have any experience/knowledge on piston to valve clearances on the n/a buick v6. I will be using a stock turbo crank, speed pro powerforged pistons, 1.77in. 1.5 ex valves, a .490ish lift cam, and a steel shim head gasket. i know these are a low compression "turbo" piston and they have no valve reliefs. i do plan on milling the block and heads to bump the compression up....how much do you think i can before i will have piston to valve clearance issues?? any light you guys can shed would be awesome.

Aaron

 

[machinegun]

I am not sure exactly what info you are looking for however here are my personal experiences. The dish in the piston is more than enough on stock compression engines. I personally would stick with stock compression if using this as a street strip or cruiser street car. Add more boost and or a degree of timing rather than increasing the compression. Some of the TSM guys were raising the compression to help get the car going quicker. I am not sure if it helps a whole lot or not but does seem to make it easier when cmoing off of a quick tree. Hope this helps.

 

[eastwoodad]

This is actually on a Naturally Aspirated build. I was looking to get to about 9:1 or 9.5:1 maybe slightly more by using the cheaper speed pro pistons. i just didnt know if anyone had experience cutting the heads and block this much. like you said i figure not too many have because of the turbo's. Thanks.

Aaron