Bigger head studs than stock?


Active Member
Who here has drilled there 109 blocks for bigger head studs? What size did you end up going with? I know on the fords they drill the blocks out to 5/8 size. Same with Oldsmobile. Has me thinking that the stock 7/16 size head bolts can’t keep the heads on at the higher boost levels.


runs with scissors
The heads don't lift because the fasteners are too weak. It's just a design limitation that shows up when you more than double the output of the engine. (or detonate the crap out of it)