500hp 408 with Hi-Po 340 Manifolds?

dustoff440 said

dyno test with 340 and magnum manifolds

http://www.moparts.org/Tech/Archive/exhaust/9.html

looks like 30 plus hp loss with manifolds over headers which is about 3/10 in the quarter which you should feel in the seat of the pants

I also agonized over the headers/manifolds decision and am running a 68-71 left 340 manifold and a r/t 360 magnum manifold with the 2 1/4 (92-93 only) outlet on the right side. I agree with moparmat2000 though, I will eat the loss as I want a street car with MINIMAL FRIGGING

Click to expand...

Looks like the big loser here is the driver's side 340 manifold as when the ran the engine with two of those piss poor manifolds, it made 20 horsepower less than the same engine with two passenger side manifolds...

The Magnum manifolds weren't quite as good as the early 340 manifolds (one right, one left) but they didn't use the early Magnum manifolds which have bigger outlets. What's up with that????

Headers make 'em all look bad...

You pays your money and youi takes your cherce... :cheers: