L31MaxExpress
I'm Awesome
My '94 C2500 ecsb (7200 lb GVWR) 5.7 had them as well. Discovered this when I was pulling the Y-pipe and broke a few manifold studs, figured weather was cold, I'd just swap some other manifolds on instead of fighting the broken studs. Nope. The others were 2", so I went to work pulling the broken studs and replacing them. Not sure if "all" TBI 2500's and 3500's had the 2.25" as the other examples I had at the time were different combos or the engines were already removed and sold, and I sold them complete with manifolds.
Richard
Makes sense. Although those were probably 45* exit on both manifolds. The G-van logs have the older 70s style exit where the driverside is straight down between cylinder 5&7.