On my 58 235 with Split factory exhaust. 3X2 Barrel Carbs (Langdons small Carter/Webers), 3/4 CAM and no head work. The couple times I took it down the track that motor ran great up to 4700 RPM where it just flattened out. That was backed by a T5 transmission and a 390 rear. That truck was very street-able and sounded great, I ran it open headers at the track and there's just nothing like an open header Six.
Mongo