Quote:

We had custom headers built and the dyno difference was almost 50HP between the ProParts and custom..
The install is in a 71 Duster, built 440, Tunnel ram, runs high nines..
As mentioned previously check out the major tube length differences of the ProParts....

Just my $0.015..




Same collector design and dimensions? Do the flanges mate up to the ports the same?
What I'm asking is, are the only difference between the two sets primary length?