BTW do you know anybody making RX8 exhaust flanges? I am thinking of
   getting a batch made up.

   Paul Lamar


   Racing Beat and Mazdatrix list the RX8 exhaust flanges, probably
   Mazdaspeed as well.
   Cheers
   Cary

   I found some headers but they won't work in tractors. No flanges for
   the block outlets however. Do you have the right links?

   Paul Lamar


   Some others - notice the part#'s are the same :) - there may be a stock
   mazda part as well N3H1-13-461B - don't know:
   http://www.mazdatrix.com/8exhaust.htm

http://atkinsrotary.com/store/catalog/Exhaust-Flanges-title0-p-1-c-673.html
   http://www.racingbeat.com/resultset.asp?PartNumber=16169
   http://www.racingbeat.com/resultset.asp?PartNumber=16168
   ~C



   Paul, If you do an exhaust flange for  RX7 and one for RX8 shouldn't we
be
  using a CNC plasma cut 321 stainless flange. Also a slightly larger area
  around te port would allow the stock double wall exhaust header to be
used.

  For a tractor installation after cutting off the cast iron flange and
intake
  port heating supply piece, turn the header upside down so that the outlet
  faces the accessory end made possible by the equally spaced rectangular
port
  openings. I have not done this yet but plan on doing it by first adding
  1-1/4" to the exhaust tube, then welding that assembly onto the flange and
  finally adding a split extension to  the outer cover and welding that to
the
  flange. This is intended to add support to the exhaust connection and
reduce
  temperature stress during cooldown by slowing the cooling rate, hopefully
  preventing exhaust cracks. Also I am just too cheap to throw away such a
  nicely made stock part, and every one I have came with the header
attached.

  george grimes

  Surprisingly you don't need SS for exhaust flanges. Mild steel works fine
  because they are so thick. I am building a tangential muffler so the stock
  RX8 exhaust manifold is of no use. The input to my tang RX8  SS muffler
will
  be telescopic rectangular fabricated  tubing.

  Paul Lamar


Not only is it so thick, it's bolted to the engine with lots of contact
area, and since the engine is water cooled, the flange can't get that hot.

Similarly, header wrapping tape, which causes the exhaust pipes to run
hotter than if they were exposed to air, can also cause increased engine
temperature and increased cooling system load.  The pipe runs hotter and
that heat is easily conducted back to the engine - most noticeable on an air
cooled engine.  The ceramic coatings (I know Paul is skeptical of their
capability) which are applied to the inside and the outside of exhaust
headers don't cause this issue.


Matt-

I don't mind ceramic coating on exhaust pipes because if it comes off it
cannot destroy the rotor housing wear surface unlike ceramic coatings on
rotors.

Paul Lamar


Ed Klepeis, techwelding@comcast.net, (270) 898-3776, has had RX8 exhaust
flanges machined with a laser cutter.

Ed told me that he sent you a tangential muffler. How well did it work?

Sandy McNabb
Renesis in a Glass Goose

Not as well as we had thought. Exhaust gas came out the cooling tube at idle.
Also the large down pipe bend did not clear the firewall. No fault of Ed. The design was defective. Other than that is worked OK. I think he made some other types as well.

Paul Lamar