Thanks for the opinions on the 321 SS. As I'm using the stock turbo, I
don't have to worry about a collector pipe and any flex between housings, as
the stock turbo manifold is very heavy and solid. Did I say heavy? This
makes the exhaust pipe requirements somewhat simpler as it only requires a
single 2 1/4 ID pipe to mount on the flange. I don't want to go to thin on
the exhaust pipe, but if it isn't necessary, I don't want extra weight,
because of the weight of the turbo and its manifold. I know it's better to
be safe than sorry, but I'd rather investigate all reasoning rather than
throwing extra weight on every time I'm not sure. I've already got plenty of
extra weight with all my fuel capacity.
Corky Kelly in his book "Maximum Thrust" indicates that the turbo reduces
the abuse on the exhaust system. I've already mentioned his believe that the
thinner metal will conduct less heat, and I can see how the turbo should
absorb most if not all power pulses from the engine, I can even see how some
of that heat energy is converted to mechanical energy, however it is also
causing the engine to produce far greater amounts of heat, so I would really
expect the exhaust system to still see at least as much heat as a non-turbo
exhaust pipe.

S. Todd Bartrim
Turbo 13B RV-9Endurance
C-FSTB
http://www3.telus.net/haywire/RV-9/C-FSTB.htm

   "Whatever you vividly imagine, Ardently desire, Sincerely believe in,
Enthusiastically act upon, Must inevitably come to pass".