My new heads have a 1.530" outside diameter, which does not clear the Crane 1.6 ratio narrow body roller rockers (gold series).

I've ordered a set of Scorpion roller rockers, as they seem to have a much larger clearance for springs.

However, I'm really surprised I hit this. Is 1.530" that much larger than stock, and has anyone hit this with Crane rockers before?

Thanks,
Dave

 

They will often hit on large diameter springs & also on some retainers.

The non-aligning units designed for 7/16" studs are machined for the larger spring & should fit without problem.

You can also grind the ones you have to clear with a die grinder & carbide burr. Strength should not be a problem as I have modified many sets without failure.