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?? thanks so much.

Aaron

 

[unboostedV6]

There's lots of room...my first motor had a .496" stick with stock 4.1 pistons, block milled .040",heads milled .050",.038" gaskets GB

 

[eastwoodad]

greg,

do you still have those 12:1 pistons that you had on your old motor for sale? I am building a N/A v6 that i will be putting in a fairly light regal. i am not really sure yet how serious i want to go. i already have a KB #1 intake 109 block, turbo crank and rods, 8445 heads that will be self ported, KB Mark 2 cam (.478/.494- off the top of my head). i am wanting to go with the speed-pro pistons because i can get them cheap but i know i need compression with that cam. any input would be appreciated. Thanks

Aaron

 

[unboostedV6]

Aaron, I have a set of "new" 3.830 Wiseco forged flat tops with valve reliefs assembled with floating pins to bushed, resized,and shotpeened rods. Never installed,let alone run. Been in storage for roughly 15 years. Very light rust on rods. $250 plus shipping - about half what the pistons cost me way back when...GB

 

[eastwoodad]

what would the approximate compression with a stock stroke crank with these pistons?

Thanks,
Aaron

 

[unboostedV6]

probably right around 12:1, depending on gasket thickness, head cc,etc GB