I use the Fel-Pro stock gaskets, the kind you put under iron manifolds, they're metal-bestos design. I have never had one leak, ever. Used them on all kinds of high compression small blocks and big blocks. A couple things you can do is to true the header flange surface with a file and the same goes for the heads. You'd be surprised how distorted some of the headers are right out of the box, I'm not using cheap headers either. On small blocks I cut the bar off of the flanges so I end up with 4 individual primary tubes and they can move individually slightly when torquing the bolts. I've never had a header crack from doing this and if you spend a little time grinding the flanges down they'll look like they came this way and the motor looks 100% less cluttered once that ugly flange bar is gone.
[This message has been edited by SY1 (edited 09-23-2001).]