Jerry Hey wrote:

 Does the rotary perform best with zero exhaust back pressure?  I am
 designing my new system  and want to go for max power.  I have a zero
 back pressure design that will also be quiet.   (Did that  get your
 attention?) But if a little restriction will help that can be done
 as well.    If so,  how much?    Thanks,    Jerry

Due to intake an exhaust/intake  overlap it is not that simple. All I know
is about 32 inch exhaust pipes with 22 inch intake for 6000 RPM
seems to be the hot tip with no back pressure.

Paul Lamar

Is that 32 inches of 2" pipe before the muffler?   How was this
number derived?  Is there a resource I can read? The Star Mazdas have
a muffler which surprised me when I saw it.   I can't believe it is
about noise when it comes to race cars.  Lynn?           Jerry

Yes.

Well two sources. The Mazda tech papers which are on:

http://www.thecarricos.com/ACRE

in PDF format and the work that Everett Hatch did.

Here is just one graph from those tech papers.

Paul Lamar

Hey Paul, with regards to exhaust length, what is the  distance between the port and the turbo
stack on your ship? Would it also be critical in length with a turbo mounted as opposed to N/A?

I am  using the stock (real short) 1989 1991 turbo exhaust manifold.
Turbo's don't seem to care about the exhaust manifold as far as HP is concerned.
I have seen a 800 HP two rotor with a short exhaust manifold.

I suspect the intake manifold makes no difference either. Just jack up the boost
a bit.

Paul Lamar
 
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