Manifolds vs. Headers

Headers tend to help HP and torque a little bit. But the few HP and TQ across the entire operating range helps more than one would initially think. They can lean out a carb, especially OEM, so compensating for that would get the most out of them.

Here is a dyno comparison on a mild 360 using a variety of OEM manifolds and headers for reference.

http://www.moparmusclemagazine.com/...pp_0307_mopar_crate_engine_exhaust/index.html

TTI headers would solve any ground clearance problems, but it does depend on your budget.

http://www.ttiexhaust.com/