Compression Increase on stock 6 bolt

[1SloEvo]

I am looking to bump up the compression some on my Laser RS turbo. I'm not wanting anything crazy, just wondering how much I can mill the head down and what thickness head gasket to use to bump the compression up a little but still have plenty of piston to valve clearance. The head will have stock sized valves and stock cams for a while, but I eventually want to go with a decent sized 272 set of cams. If someone knows off hand the head thickness once milled to bump the compression up a bit and still be fine with valve clearance, please let me know. Thanks.

 

[BogusSVO]

I would not mill the head...

do a piston swap if you want more compression.

milling the head too far will cause oil issues to the HLAs, and the turbo if you feed from the side of the head, also you will change the cam center to crank center line, and this will affect your cams to crank time, if you do not have adjustable gears and degree the cams in.

new thickness spec is 5.200

mitsu allows for a COMbinded total of .007 from the head and block
AERA allows for .015 from the head

 

[rstchris]

I have a total of .018 taken from my 6 bolt and it's still a lazy pig at low rpm. If you want a little more power without putting in mad work just run 1-2 more psi. BTW .018 and Web street grinds and no valve damage.

 

[diambo4life]

I have a total of .018 taken from my 6 bolt and it's still a lazy pig at low rpm. If you want a little more power without putting in mad work just run 1-2 more psi. BTW .018 and Web street grinds and no valve damage.

Piggishness at low rpm has more to do with your cam selection than low compression in my opinion. I tuned a GVR4 with those Web 264 grinds and it wouldn't get out of it's own way at low rpm. Big difference between that car and mine despite them having the same exact C.R.