Discussion Starter · #1 ·
Got a 555 BBC Pump gas motor 11:1. Alot of cam. Car is street/strip. Shifting at 7,000. Makes 850hp. What size header and what size tubing. Was thinking 2 1/4 header into a 3.5" collector and 3.5" exhaust thru a set of delta force race mufflers from flowmaster dumped at the rear axle. Is 3.5" enough for this combo. I would go with 4" but I don't want to sacrifice midrange power and torque unless it really needs 4" exhaust.