70 duster getting some boost..
its actually 1 1/2 which actually measure out to be a hair under 1 3/4 inner diameter 304 stainless schedule 10 butt weld fittings.. they are really nice to work with and are nice and thick so i wont have to worry about it cracking or falling appart like thin cheap manifolds you can buy.. i just bought a bunch of 90s and some straight.. cut the 90s to the desired angle and they work great..