garrettpen

What size combustion chamber do theese heads have stock?

WKMCD

iTrader: (2)

Richard at WCCH measured it at 69.8cc.

garrettpen

Thanks.

WKMCD

iTrader: (2)

I think when I worked the numbers for my motor, I came up with 11.17:1 compression on the 402 with 2cc pistons and .050 gaskets.

SStrokerAce

iTrader: (2)

which for you means you gotta mill them puppies!

WKMCD

iTrader: (2)

It's your cam we're going to run...

How much to mill? PM me if you want.

garrettpen

what would the cc size go down to if say you milled .030?

SStrokerAce

iTrader: (2)

Around 65cc

Bret

JZ'sTA

iTrader: (23)

yep figure around 6-7 thous for every 1cc.
so 69.8 cc's minus 30 thousands should be close to 65-66.

airflowdevelop

there's plenty of flange on these heads....cut the pigs!!!


As measures with DcI seats (69.6cc) stock.

garrettpen

Thats a good rough formula to know, And milling that off you would still have enough clearance between the valve and the cylinder wall?

See5

iTrader: (53)

In talking to some very knowlegeable guys who do work on these heads and manifolds for GM, it not clear yet that these heads are a slam dunk due to port size issues. They flow like crazy but they are truck heads. Not only that, if you start seriously milling the heads you can expect geometry, port match and manifold fit issues. Not to say they don't have big potential but-