Bypass hose fittings

Longgone said
I have a `67, 273 intake that has a 1" threaded opening with a 3/4" adapter for the actual hose, so you could both be sort of right. Diameter may be year specific?

Good observation. All my stuff is the newer stuff like 70 up. I've seen the older ones but it's been too long and I don't remember them.