I had my heads milled .020 and I went from the thick felpro head gasket to the .015 shim gasket ( i think the thick one is .040)

I didnt think it would be so much but it was enough to make the manifold not sit right, to make matters worse there is a port mismatch now and the bottom right of every port has a ledge which has to be killing airflow. I also had to finagle the manifold on there just to bolt it up. Didnt have the time to have it machined.

I plan on fixing this. According to lingenfelters book for .030 worth of machining ill need to machine the side of the intake manifold .037 and the bottom .052

my problem is that added up I took off .045 and my heads may have been machined before since i cc'ed them at only 52 ccs (maybe .010 removed before?) anyways if i could get it to sit just how it was before the milling that would be fine so .045 less equals what on the manifold? Lingenfelters book only gives numbers for .030 and less


anyone?

Pablo

 

For every .010" you remove from the head or block

yu take .0123" off the intake port face on eith the head or intake.

And .0173" off the bottom of the intake.

The .015" gasket is the origional assembly gasket from GM.

the .040" is a thicker replacement.

Milling the manifold face or bottom will only raise or lower
the manififold ports relative to the head ports.
It will not correct a alignment problem of the sides of the ports.