If you mean the studs in the head that the intake and exhaust manifolds mount to, as far as I know they are all the same size. Granted that hasn't stopped me from using a longer stud in a pinch, then adding a washer or two between the nut and the triangle washer.

The studs are all the same size.

The key is making sure that the correct washer and fastener is used when re-assembling.

Fat circle washers and BRASS nuts go on each end on top, there is 1 fat circle washer with a regular nut smack in the middle on top, the remainder get triangle washers and regular nuts. Be sure not to over-tighten the manifolds.

~THOR~