Recently purchased 13b turbo, would prefer normaly aspirated
 13b.
 Anyone interested in trade? Located in Howell MI, or
  trade
 turbo and associated parts and rotors. Made decision
 that
 my needs don't require turbo after all.
 C. Smith
  What year turbo engine Craig?
  Paul Lamar

  Paul, I have yet to take the photo of turbo, for you to
  date
  the engine. Classes ended yesterday, so I'll try to
 get
  the
  photo today after work. Engine is still on the pallet in
  the back of my truck.
  C. Smith
If it is just one turbo it is somewhere between 1988 and
  1992.
  It makes a large difference. If it is 1990 to 1992 is
  better
  as the first ones 88 to 90 cracked a lot.
If it has two turbos it is highly valued 3rd gen RX7
 engine
  that
  has a much more robust construction over all. Designed for
  up
  to 280 HP.
Paul Lamar
 Paul here are some pictures. Please tell me what I have.
  If you need a different shot please describe it. I'll
  try again.
  C. Smith
Hmmm hard to say. Those pics are badly out of focus. If
  they were
  done under florescent lighting that might be the problem.
  Use an incandescent bulb and take the pictures over
  again. Either that or use manual focus if your camera has
  that
  option. Also remove the heat shield from around the turbo
  for a better look.
My wild ass guess is it is a 90 to 92.
  Some people might be able to tell from the intercooler
  but not me :)
Paul Lamar

 My apologies about the quality, I was in a rush to get them
 out, and
 didn't look at the final result before sending them.
 It's cramped in
 the back of the truck, tiny screen on camera, and had
 glasses on that
 focus too far out combined to give a bad result.
 Will have to wait until I can borrow a friends lift to get
 the engine
 out of the truck.
 Is it reasonable to just replace the rotors with NA rotors?
 Are there
 any other differences in the rotors(other than compression
 ratio),
 turbo/non-turbo, and or year to year?
 C. Smith

Yes it is possible. 13B 9.7 compression ratio rotors are
 expensive and hard
 to find. With a p-port I think cheaper RX8 10:1 rotors
 would work.
 It will have to be balanced.
 For an aircraft I would not mess with side ports. Too hard
 to get
 porting and manifold to work for as little as 200 HP at
 7500 RPM.
 About 250 HP is possible at sea level with a p-port at 7500
 RPM.
 You don't need to use all the power at sea level but up
 at 12K you will need it.
Paul Lamar


Thanks for the response. I was planning to P-Port. Who or where
do I go for balancing, and what all needs to be balanced? I think
I have found some rotors, and they are not prohibitively expensive.
Planing on new seals all around, as much of a complete rebuild as
I can. The P-Port process requires complete tear down, may as well
get everything to new condition anyway. I notice you describe both
a bonding and welding P-Port process. Pros and cons, which would you choose?
C. Smith

The only place I know is Mazdatrix in CA. I think they may
be able to do it with just the e-shaft, the counter weights
and the rotors.

But I am sure you can find somebody in Michigan. The balance
weights need to match the rotors.

If I had a super accurate dwg of the balance
weights and the exact weight of the rotors I could come pretty
close using my Rhino 3D program as it locates the centroids
on the balance weights. Here are the formulas.

I choose the welding hands down. It is real easy. Bonding is real
tough to insure you don't get a water leak into the engine.
IMHO some sort of application of pressure is necessary
to insure the epoxy flows into all the crevices.

Paul Lamar