trickability

Can someone tell me how much the heads are milled when getting ported

Just Enough

Unless you have a non stock cam with more overlap you really can't raise the LS7s compression ratio very much with out pump gas problems. Stock it is running somewhere around 8.7 to 8.9 dynamic. If you have an aftermarket cam search for a dynamic compression ratio chart with the cam timing event specs vs static compression ratio.

WFO

Tomorrow Wed 3/18..getting my 08 Z LS7 heads milled .40". Bringing the compression to 11.6:1. on pump gas. Going with the QM550 cam. Quality Motosports doing their magic once again.

972/754-3387 Call Q.M. and ask Patrick for details.

dfinke23

It varies depending on your valve clearance, which is different depending on your cam specs and rocker ratios. I have somewhat of a high lift cam so I only went .020". With stock gaskets, that left me with .072" clearance on the intake valves. The general rule is not to go below .080", some say .050" is really pushing it but I feel safe where I'm at, I'll just set my rev limiter to 7200 instead of 8000 rpm.

Here is a cool CR calculator:

http://www.rbracing-rsr.com/compstaticcalc.html

trickability

let me know what kind of power you get with that combo. I am looking at the same thing on my o6 z

dfinke23

I'm expecting 30-35 whp.

6Speeder

According to my calculator milling the LS7 heads that much will give you 12.36:1 static compression, not 11.6:

http://www.wallaceracing.com/millcalc.php

Z-O-NO

Yeah, and if I understand him right, a CAM and milled heads should give you more then 35 HP...these Ls7's Love aftermarket cams!

0Myhardtop

I all depends on the car, the cam and the tune. Many people like to mill the heads and then put stock size gaskets back on and thus negating the mill job and then expect to see a big jump in power.

I find it best that milling the heads .40 and then running .40 thousandth thick gaskets performs better and more consistent especially with a cam.

We are currently running a milled heads/cam kit special for $3,000 tuned and installed!!!

Thanks,
Carlos

Whis9

Sorry to bring up old thread, our the stock gaskets too thick? Getting my heads done soon, so trying to figure all this out, thanks

Funkybird

I'm curious too, I got my head/cam setup from Carlos and put on new, stock gaskets after milling the heads .045?

amdoverclocker

If you have a stock gasket... then mill it .0XX and put a stock gasket back on.. why would there be a difference other than what was milled?

Mark2009

JMB

Ditto, another perfect combo with just the right quench!

ian08

does anybody know how much .30 and .40 milling change the cc of the head 70cc is stock right

edmundu

ROM is in the .0067-.007/cc range.

.030 = 65cc
.040 = 64cc

TRSCobra

I only went .020 due to 92 octane and DCR concerns with the cam I'm running. Safe > sorry and you can never put material back on that you mill off.

amdoverclocker

No but you can get a thicker gasket.

londonk

WOW thats cheap what a deal …… plus you cams are the best

ttx350z

Do keep in mind that was posted back in 2009.