1968 GT500 Exhaust to H-pipe Studs

[8T03S1425]

Are the threaded holes that secure the H-pipe to exhaust manifold 3/8"-16 or 7/16"-14? I believe both threaded holes take studs. RH manifold has 1 through hole and 1 blind hole. LH manifold has 2 blind holes.

I'm chasing the threads. The 3/8"-16 seems correct, but the threaded holes seem like a bigger tap would be better.

Steve

[roddster]

  They  are 7/16 coarse thread

[8T03S1425]

Thank you roddster.

The more I thought about the, the more I thought I should order the studs from a vendor. With them in hand, I'd be able to measure the stud for dia and thread count. I need them anyway.

Steve