Ok, so i'm about to rebuild a motor for boost. Im going to use the Howell 8.6 bottom end kit, and want to have my head shaved while its getting cleaned. How much should i get it shaved to bring compression back to the stock 9.6:1? Also, where should I look to get some new valve springs and maybe some 2mm oversized valves? Thanks in advance for your help.

Don't shave the head to raise compression when you are rebuilding, just pick the compression pistons you want and go with those. You can get stock compression pistons from howell, may have to order but JE does make them. Shaving the head for raise in compression is not worth it with a rebuild being done, there can be issues with timing. Just pick the compression you want out of teh pistons.

Una salus victus.
He will triumph, who knows when to fight, and when not to fight. - Sun Tzu

Michael J. Kulaga
e-mail: Michael_97RS@2gntDSM.zzn.com aol IM: MJKulga
http://highlander.dsmpower.com/

All motor in the making.

Injen CAI, 55mm TB, P&P Intake Manifold, Crower Stage 2 Cams, Hooker Header, GS-T Muffler, AFX UDP, S-AFC, 8.5mm Magnecor Wires, Crane Fireball HI-6DI2, FU/RU/RL STBs, TSW Blade 17x7.5, Bridgestone Potenza RE730, Front KVR Cross-Drilled Rotors & Carbon Fiber Pads

To Be Installed: P&P Milled Head, Rear Disc Brakes, Rear KVR Cross Drilled Rotors & Carbon Fiber Kevlar Pads, SS Brake Lines

It would make no sense in getting lower compression pistons and then milling the head to put the compression back to stock. If your goal is to get the stock 9:6.1 compression, then just buy stock compression pistons.

9.6:1 is still unsafe for boost for a street car.

Get the head milled so it's flat, if need be, but don't remove enough to raise compression.

Get the 8.6:1 pistons and be boost friendly.

If you don't have a turbo kit yet, when you reassemble the motor, remove a layer from the head gasket, and that'll give you a bit more power. You'll have to install a full head gasket before you add the turbo.

>9.6:1 is still unsafe for boost for a street car.
>
Thats old thinking my friend, old thinking.

New racers are showing us the other way works even better, its all in the tuning. Look at Mike Crawford, running something like 12.5:1 or whatever he is at now and along with that 30lbs of boost.

>New racers are showing us the other way works even better,
>its all in the tuning. Look at Mike Crawford, running
>something like 12.5:1 or whatever he is at now and along
>with that 30lbs of boost.

Yes, but not on 93 octane and using the stock ecu to run timing? No way. Even a MSD would not be able to contain potential detonation at that CR and boost.

IMO, if OEM manufacturers could reliably pull of such high CR's, they would in order to attain better gas mileage and overall efficiency. But as evidenced, by today's production turbo cars, they stil hover around the high 7's to high 8's.

High CR's such as those run by single digit racers should not be a model for anyone here, unless they have some serious bank to put in their car.

Exactly, by street car, I mean stock computer, etc. You could run 12.5:1 with 20psi with a EMS, and probably well over 12 hours on the dyno, but it wouldn't be streetable, and don't even think of using pump gas.

And Mike Crawford runs 15:1 compression with 38psi and a 150 shot of nitrous. Insane? Yes. Fast? Absolutely.

if 9.6:1 comp is unsafe to run on a street car then why are there a ton of guys on here running stock 9.6:1 comp on stock internals and boost? even if you did get 8.6:1 and did the shaving to get 9.6:1 compression, compression is compression. Either way you will have the exact same amount of compression...

Boosting on stock compression is NOT unsafe. The higher the compression the tighter your margin for error becomes. But 9.6:1 is by no means close to messing everything up. 12.5:1 the margin gets narrow./

Una salus victus.
He will triumph, who knows when to fight, and when not to fight. - Sun Tzu

Michael J. Kulaga
e-mail: Michael_97RS@2gntDSM.zzn.com aol IM: MJKulga
http://highlander.dsmpower.com/

All motor in the making.

Injen CAI, 55mm TB, P&P Intake Manifold, Crower Stage 2 Cams, Hooker Header, GS-T Muffler, AFX UDP, S-AFC, 8.5mm Magnecor Wires, Crane Fireball HI-6DI2, FU/RU/RL STBs, TSW Blade 17x7.5, Bridgestone Potenza RE730, Front KVR Cross-Drilled Rotors & Carbon Fiber Pads

To Be Installed: P&P Milled Head, Rear Disc Brakes, Rear KVR Cross Drilled Rotors & Carbon Fiber Kevlar Pads, SS Brake Lines

exactly what i was trying to say...just go with forged 9.6:1 compression pistons and dont shave your head because you will then have idling problems.