John:
Don't understand your comment; the straight 2 1/4 and 2 1/2 in pipes outflowed all the mufflers; in certain cases near 100 cfm.
Richard:
Help me out here; I was of the understanding that the neg. pulse was generated where the header pipe dumped into the collector and was reflected back toward the source and that was a functions of pipe dia and length; there are std. formula for setting this; normally around 38 -42 inches is typical. Will coating, which increased heat, raise the Mach no. and thus require a longer pipe for scavaging for the same rpm?
I didn't know the side pipe(muffler) lenght had much effect on overall exhaust performance other than back pressure. Could you elaborate on how/what the side pipes contribute to the overall exhaust design in tech terms? Also there is a general comment that Cobra style 4 into 1 pipes/mufflers are a poor design and waste alot of power. I don't understand or believe this common folk story. Any comment/observations?
thanks
gn
