Jeff, here are some renderings of that alloy end house I sent.

 The replaceable sheet metal wear surface is .090 4130 heat treated
 to Rockwell 64 and Blanchard ground on one side.

 What would it cost to make one of these out of billet.
 We could build up an engine and test it.
 The real market is one rotors where engine weight is critical.
 This should save up to 20 pounds.

 Paul Lamar

  Paul

  Talking 6061-t6?????  A day's worth of machining and set-up, really
  more..I'd do it for you $350 plus material..deal...Looks like 38
  lbs(12x13x2.5) and 6061- billet is about $3.25/lb.

  It will machine down to 12 to 15 lbs....

  jeff

  I deleted your SW jpg Jeff as it was too confusing since we are talking
  about an aluminum billet end housing.

  That is a bargain for an aluminum rear rotor housing. Racing Beat
  charges $1300 and the coated wear surface is unproven. For a one rotor
  engine $350 would be well worth it. If we get some interest in this I
  will do a front end housing design as well. If one bought a new Mazda
  end housing it would cost one about that. This means you can buy all the
  parts for a 125 HP all aluminum one rotor Mazda based engine for less
  than about 2 or 3 thousand dollars less the PSRU. Weight with PSRU would
  be well under 200 pounds.

  Can you cut down a stock 2 rotor E-shaft as well?

  Paul Lamar

  Count me as a customer for both ends, and I'll buy a center housing if
  one is produced. These are all great advances in design. Still waiting
  to hear from the variprop guys about the weight and dimensions of their
  300hp hub. I don't know if they are still in business, no answer to
  e-mail or phone message. Going to need that info to determine if mount
  needs to be stretched a bit for CG.
  C. Smith


  Paul
  Count me in as a customer for Both as well... I had planned on
  buying them from Racing Beat at some point but this would be a better
  option and I can then pick up their center housing. Just One question,
  the design is for a 13B P-Port right?  Between this and the adaptor plate
  weight reduction, P-Port with the sliding throttle it will make a very
  nice package.

  Mike C.

  Right P-port only. Too complicated for side ports.

  Paul Lamar

 PAUL

 You talk about the side plate inserts of 4130 .090" and R65 blanchard
 ground. Is this ground in the aluminum housing to keep parallelism  and
 fit to the housing?  Is this nitrided  as well of or left bare???  The
 render I was sent shows no support behind the plate, should there be
 something in the middle? Your thoughts...

 Jeff

 Yes there should be some support in  the middle. That is provided
 by the stock rear main bearing holder and phasing gear in the two rotor
 version.
 Details not shown but I will add them for you when I get
 back.

 In the one rotor version the rear main must be modified to
 eliminate the unneeded phasing gear and give support to the
 oil drain back from the rotor.

 Paul Lamar

Paul, This is just a note on aluminum end house material. I was going to
use this for my six rotor side housings without any ad on coatings. I am
currently  in favor of a cast nickel iron wear surface in magnesium
housings. Nothing against the full aluminum side housing of the 398 aluminum
17% silicon alloy which would be lighter. However the heat transfer into the
aluminum is much higher adding to cooling load and possibly reducing power
output. This heat transfer  seems to be a drawback of the aluminum rotors
made from this same material. I got the attached report from somebody making
aluminum racing rotors for drifter cars as a download on the internet, but
can't find that file in the terabite of unorganized downloads to read
"later when I have time".
Also just thought I might tell you I REALLY like your offset combination
PSRU adapter/motor mount plate starter mount. It is light, multipurpose, has
a short load path, and avoids mounting the engine off the oil pan bolts.

george grimes

We discussed that alloy before. I think it is worth a try
for rotors. If you can reduce the weight by 50% the max RPM
could go up to 15,000 or so and so too the HP.

Paul Lamar