Subject: Turbo Rx8
From: paul lamar
Date: 9/14/2016, 10:50 PM
To: A10-Me-Earthlink


   She runs!!!!!

   https://youtu.be/yqRx-hH8xsk

   https://youtu.be/PGN509s67oU

   Is anybody running the slide throttle? I'm finding it hard to slide
with engine running due to the suction. Now mind you, I don't have any
mechanical advantage or throttle cable setup yet. I'm using a threaded
bolt to test with.  Can someone share their setup with the slide
throttle / lever quadrant used?

   With the engine on the test bench, what safe rpm would be good
without any load on the crank? I'm aiming between 2000-3000 right now.
Not sure if it matters without a load on engine?

   - Matt Boiteau

   You will have to put a 2 to 1 lever on it.  That will reduce the
force by half.
   The travel will be 4 inches at the top of lever. The lever can be
six inches long.

   With the 5 square inch area throttle nearly closed and 15 psi
(atmospheric pressure
   at sea level ) across it the force is 76 pounds.
   Assuming you did the Teflon liner properly  and used the right kind
of Teflon
   the coef. of friction for  Teflon is below 0.1 so that is 7.6
pounds of force
   on the cable.

   As you open the throttle the pressure drop across the throttle becomes
   less and that number will drop.

   Historically slide throttles have used linear ball bearings but
they are very
   expensive and subject to jamming with just a little bit of dirt.
They usually cost
   over a thousand dollars US. The Teflon liner will tolerate dirt and
embed
   it in the soft Teflon. Many small slide carbs have the slide coated
with Teflon.
   The SU is a well known example.

   The e-shaft is absolutely  the last thing you need to worry about since
   we are using a stock e shaft and we are getting 650 HP. The part of the
   e-shaft next to the flywheel is the most highly stressed part and that
   has held up with over a 1000 HP on a turbo 4 rotor. Stock e-shaft and
   stock diameter. The stock e-shaft is atomic bomb proof :-) After
all It was
   built in Hiroshima. Sorry! politically incorrect joke.

   IT MATTERS!
   BE VERY VERY CAREFUL. The engine will run up to very HIGH RPM's
with no load
   and then seize. I don't know how high WITH oil pressure but WITH
OUT oil pressure
    it seizes around 10,000 RPM very roughly speaking. It has been
done so don't try it again :-)

   Of course there is a rev limiter in the stock RX8.


   Paul Lamar


Does anyone have any pictures of their slide throttle / lever / quadrants?
Just wondering what setups people have so far. I'll go to Aircraft spruce
tomorrow and look for parts.

I forgot to post my setup before.

ECM: MegaSquirt MS3
Injectors: 4 x RX8 yellow (moddifed to flow 820cc/min each)
Fuel Pump: 2 x Walbro GSL392 255LPH (primary and backup)
Coils: 4 x LS2 GM Yukon truck with heatsink
Spark: NGK RE7C-L & RE9B-T


Just need a nice PSRU on the front :)

- Matt Boiteau

Matt, get some RX8 coils those piston engine coils where designed to
spark half as often despite the heat sink.

Hang in there. Neil is working as fast as he can on the PSRU.

You might have to make a throttle lever. What kind of tools do you have?
Do the home/hardware  stores sell aluminum bar stock in Oz?

Go to Aircraft Spruce? I thought you were in Oz.

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

I hate to be so blunt about it but some of the things Tracy did
were down right dangerous. Using those four stroke coils was one
of them.  He was an electrical engineer so he should have known
better. Every auto mechanic in the world knows that a four
stroke engine fires every OTHER revolution. A rotary
fires  EVERY revolution. If you use those coils your going to heat
the hell out of them!!! PLEASE don't kill your self in a rotary.

Paul Lamar

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