Doug,

The only method to correctly hold a head down on a YB is Genuine Cosworth std head bolts. I have tested every method extensively (i.e. 6 long studs, 10 long studs, ARP, std) and done a detailed survey of block distortion, residual clamping force remaining, block cracking and effect on head flatness and distortion.

The results are STAGGERING and not what everyone would expect!!