1. If you are using Tracy's gear box it is a good idea
  to use the 3rd gen RX7 13B high capacity oil pump.

  2. If you are using a turbo make sure you have
  separate oil lines from the main oil gallery in
  the block going to both the turbo and Tracy's gear
  box. Do not run one line and T it to both the turbo
  and the gear box.


  Paul Lamar


 Sounds ominous..  Hopefully Dave has a runnable airplane for racing.

 Good information though.


 Matt-

 Paul,

Did I miss Dave's posting describing the gearbox issue?

Mark S.

Not yet. Hopefully Dave will explain as soon as he gets
home. Also we will learn a bit more at the heat race tomorrow.

On another matter the oil pressure sender has been failing
every 20 hours or so. Larry Childs thinks it is because
it is not mounted on the firewall and connected to the block
with flex hose. Larry is Crew Chief on the unlimited Steadfast
400 MPH Yak and a long time rotor head.

Summit Racing has a large warehouse and retail store here in
Reno so we went down there and bought a old steam gage 200 psi
mechanical oil pressure gage and installed it.

Here are some pictures.

------------------------------------

One other thing we are learning is apparently the engine
tension bolts are lengthening under high boost (over 45 inches
of Hg) and allowing some small amount of combustion gas leakage
into the cooling system. Mazdatrix among other are dealing
with it.


http://www.mazdatrix.com/studkit.htm

I am still looking for 12.5 MM (1/2 inch) titanium studs
to save the weight as 16 12.5 MM steel bolts are quite heavy.

The modulus of elasticity  of titanium is about 16 million
while steel is 30 million.

The area of the stock 10 mm tension bolts is 78 mm
while the area of the 12.5 mm bolts/studs is 123.
That makes the 12.5 mm steel bolts/studs  almost
twice as stiff.

So the 12.5 mm titanium studs do not appear to be stiffer
(due to the lower modulus of elasticity) than the stock
steel tension bolts. Only weight is saved over 12.5 mm
steel.

http://en.wikipedia.org/wiki/Young%27s_modulus

Another factor is pre load. If one can torque the tension
bolts higher that delays the expansion to a some what
higher boost level. How much I have not figured out
yet.

IMHO it is best to stick with 12.5 mm(1/2 inch) high strength steel.


Paul Lamar