I agree, FED look best with Zoomies, yes on a dyno a 4-1 exhaust will make maybe another 20 hp, but John is plan on running a big BBC in brackets, right, so he'll make more than enough easy power, John wouldn't need that extra 20 hp. John may have a bigger problem slowing down to the bracket he wants. Plus then John can run nostalgia classes/ events.
Jon