Milling heads

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Feb 22, 2006 | 09:34 PM

SFengineer

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Racer

Joined: Dec 2004

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From: Alameda Ca

Milling heads

I was looking into getting some milled heads to bump my compression ratio up a bit. Does anyone know the amount needed to be milled to achieve 11.0 or so compression? Also, would there be interference problems running 1.85 lifters? Lastly, any idea of gains, if any besides efficiency? Thanks!

Feb 22, 2006 | 09:59 PM

WALLstAL

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From: GARDENA Ca, State Of Konfusion

St. Jude Donor '05

Milling approx. .030 and using a head gasket thickness of .040 or milling .040 using a gasket .045 should get you there.

http://www.c5frc.com/calculators/Com...Calculator.htm

Feb 23, 2006 | 06:35 AM

Blow Torch

Melting Slicks

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From: Dublin GA

You reduce your chamber volume 1 cc for every .007 milled from the head surface. With stock pistons, gaskets and block, a 62 cc head should give you around 10.95 - 11.0-1

Feb 23, 2006 | 07:04 AM

Shane_S

Drifting

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From: Dallas Tx

Be sure to take piston to valve clearence into consideration when doing something like this. the .600 and bigger cams dont like milled heads unless you fly-cut the pistons.

Shane

Feb 23, 2006 | 11:39 PM

SFengineer

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Racer

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From: Alameda Ca

thanks guys. I'm going to have them milled to 60-61 ccs. As far as gaskets go, what is "stock" size, .040 or .045?

Feb 24, 2006 | 04:39 AM

Blow Torch

Melting Slicks

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From: Dublin GA

Depends on the year. 97-98's gaskets were supposivly a little thinner because the heads had a larger cc. I can't get a clear answer from the chevy parts dealer, but the MLS gaskets are between .051 and .054. The graphite are supposed to be thinner, but I'm not sure how much.
Don't forget to have the intake sides milled if you're taking that much off.
Check PV clearence like SS mentioned

Feb 24, 2006 | 09:37 AM

9secondflat

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From: sterling ct

be careful as when you mil the heads it changes the angle that the intake will seat- also milling heads increases power less than 2% yet raises the changes of detination....

Feb 24, 2006 | 01:50 PM

SFengineer

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Racer

Joined: Dec 2004

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From: Alameda Ca

Quote:

Originally Posted by 9secondflat

be careful as when you mil the heads it changes the angle that the intake will seat- also milling heads increases power less than 2% yet raises the changes of detination....

Very sound advice. Will milling .030 off affect the angles enough to worry about? I was told my P to V issues won't be a problem, do you think differently?