STUCATZ

Looking for someone to shed some light and point me in the right direction in regards to milling the heads on my z06. I just picked up a stock as a rock '07 Z06 with 5900mi. Having a previous C6z my intentions were to get some good power with H/C + supporting bolt ons while the head issue gets rectified.

I've purchased a Vararam, TSP 1 7/8 headers w off road X pipe, MSD intake with a NW 102mm, BTR stage 4 cam + dual springs and trunnion upgrade, ATI super damper. I'm hoping that with ported heads from Katech, I'd be able to put down 600hp.

Not to go on a ramble here but I've been getting conflicting information regarding a BTR stage 4 cam and head milling. This also includes info right from the sales staff at BTR. I've been told not to mill the heads as fly cut pistons would come into play, I've heard from another person that you can mill .40. From what I gather here on the forum, people that have this cam have .30 milled heads with no issues.

What is your take on getting the heads milled with this cam? Would I be safe with a .30 mil to help me reach that 600hp mark? Any feedback is certainly appreciated!

jayyyw

No issues with the BTR 4 and a .030" mill.

STUCATZ

What kind of power are you making if you dont mind sharing?

jayyyw

I don't run the BTR 4, but I do run a cam with more lift. I make 646whp.

STUCATZ

Solid numbers! Thank you

NemeZ

STUCATZ

I'm thinking 93/94?

AzDave47

My HCI LS7 had heads milled .030. I run the Katech K501 cam (about .66" lift intake and exhaust) and 91 octane gas. With the crap gas the tuner had to retard timing so max advance is only 19*. Still 605 rwhp, 521 rwtq.

STUCATZ

I've heard good things about that cam.... 94 is pretty accessable all over the place here in Toronto Canada

AzDave47

Right now I'm having a forged bottom end done. The heads were sent back to WCCH to be checked after 12K miles on their original rebuild and the valve guide clearances were .0011 or 12 in the top and middle and .0016 at the bottom. The original HCI build was done at 46K miles, with new OEM exhaust valves, Katech TiMo intake valves and CHE bronze guides.

STUCATZ

Very nice set up. Seeing as how these ls7's are grenading at any time any place, I didnt want to chance it even with under 6000miles - so my thinking was that a huge cam would be cool while the heads are getting fixed LOL

Apocolipse

Just seems the 94 doesnt take a lot of timing without the sensors picking up a bit of noise. Mine are shaved and can only run 16deg peak tq then slowwwwwly ramp to about 20 at redline.

STUCATZ

I was just worried with all the dif info I was getting even from BTR ... I think a 0.30" mill will be alright with those cam specs. I initially thought a cleanup pass was good enough but to squeeze some more power they'll have to cut em a bit

Apocolipse

Just be prepared to run lower timing is all. Had to reduce mine at part throttle quite a bunch. Plus those damn petro 94 are a pain to find along the highway...

STUCATZ

Would it all be possible to hit the 600hp mark with a good port job & no mill?

Apocolipse

Milling usually only adds 10-15whp if your fuel allows. Grab a typical dyno of btr4 and take that off.

jayyyw

Not likely. Are you planning on an upgraded intake manifold? Unless you want crank hp, then that's more obtainable.

STUCATZ

I have an MSD manifold with a Nick Williams 102mm TB

MTPZ06

Maybe a compromise at a .020" mill. Yes its a pain, but you can always mill more off later if you want, but you can't put more back on if you went too far for your build.

Apocolipse

Or just do a clean up and worry bout it another time. Im sure wont be the last time the heads are off haha