One of my
brothers old buddies had his exhaust rigged with a pair of 3"
electric aircraft fuel valves. Switch up on the dash ran the exhaust thru a
Caddie quiet set of mufflers, down and it went out about a foot behind the
front wheels with no restriction of any kind. Not only rather loud, but
shot flame a fair distance.
Since the fuel valves were undoubtedly aluminum, I would wonder how long
they lasted!
He drove it at least a couple years and maybe 40 to 50k miles mostly cross
country. I think they were stainless steel though.