how much will i have to take off them to get them to say 45 cc? and how much for 50cc?

 

You'd have to cut off quite a bit, and probably have the intake machined too to make everything line up again. I doubt you can even cut off that much without having problems running into the valve seats, from what I've heard.

Why would you want to do this?

 

It can't be done. Just get some dome pistons.

Rich

 

Larry Hamilton (Speed Inc) got his down to 46cc, so it can be done.

I'm not sure it's something you'd really want to do simply for the sake of increasing compression,
to be honest, I don't think I ever asked him why he did it. Maybe I should?
IIRC, he has an in-house machinist with quite a few years experience port them.

(See page 29 of this month's GMHTP)

 

The deck would be so thin as to make the heads useless, IMHO.

Rich

 

really? i thought stock lt1 heads were 54cc? and deck thickness does become a concern...thats why i was wondering how much...

and ive got -23 cc pistons and trying to make the motor good for n/a for a while and spray it until i get the turbo kit built...

 

dont worry about it that much, because once you mill them, they're going to be worthless for a turbo build.

 

i wouldent use them in a turbo build...just for now while spraying the car...ill do some afr's...boosted id like my compression low 9's but all motor closer to 11 the better

 

.060" removed on the flat to get 45cc

But, they should be angle milled though to get that kind of chamber size, and either way the decks will be very thin after cutting and not ok for spray or boost. Booth have the same effect of raising cylinder pressure and need strong decks.

 

yeah im aware...i loooked in jegs and summit anyone make a thinner cometic gasket then a .040?

and i redid my calculations and i might not be that bad...54cc chamber -23 piston 4.04 bore and stock stroke should make me about 9.8:1

 

Depending on your deck height you could us a .026 gasket available from a few companies, Victor Reinz or Mr. Gasket. I believe Cometic offers a .027.

After chamber porting and a .032 I think it was milling my heads are 53.Xcc