Paul,
           I'm just starting the disassembly / inspection of my 20B for the
       purpose
           of an aircraft conversion.  The thing that seems to be worrying
       me the
           most is the water pump.  That thing is huge, or at least it
       sticks up in
           the air a mile over the top of the engine block.  And....the
   pump is
           cast iron in an aluminum housing....very heavy!!  Is there
   some way
           to modify, or preferably another pump that will mount in its
       place that
           will solve these issues?  This thing will NEVER go inside
   the engine
           cowl?

           Thanks again!!
           Don Mitchell

           No problem. Not to worry.
           I'll give you a step by step on how to cut it down with
   pictures. I
           did one for Bulent and his is working and cooling fine.
   Later today.


           Paul Lamar ...No rotor no motor.


       Don,
       If I can jump in here with a comment or two.  Yes the 20B wp is
   big and
       heavy.  I'm in the process of converting my 20B to accept the much
       lighter Renesis front cover and wp, saving 6# and get the better
   CAS in
       the process.  There is one bolt that will have to be drilled &
       tapped, but that's the only mod that I could see.  If you don't
   want to
       change the entire front cover, you can cut the wp section from
       the Renesis front cover and just use the wp section on the
   20B.  Since I
       wanted the newer style crank mounted CAS, I will be using the
   entire
       Renesis cover.  The coolant inlet/outlet on the Renesis is better
       suited for a/c purposes.

       Mark S.
       Lancair ES - N/A 20B

       Not so fast guys. The 20B impeller is a much better design
       than the RX8 impeller. The RX8 impeller is the same as the
       third gen. I think Mazda re-designed it for low average power
       street  car use to cut the WP power and improve the BSFC
       slightly. It seems to work on Tracy's RX8 2 rotor engine.

       Before I did something like this I would install a CHT
       sensor near the lower spark plug on the front rotor housing
       (tractor 20B powered airplane). Cooling wise the front end
       housing is the least well cooled. Particularly on the 20B.

       Paul Lamar ...No rotor no motor.



   Paul,
   Yes, I did the CHT mod as shown in ROTOR_HOUSING_THERMOCOUPLE.JPG when I
   had my engine disassembled and installed a thermocouple in each rotor
   housing.  So, now I can monitor the temps as you advise.  Does anyone
   know the flow rate of the Renesis wp?

   If I recall correctly, Tracy is running a Renesis wp on his RV-8.  Since
   he hasn't flown (that I know of), we'll have to wait a little longer to
   find out how well it cools.

   Mark Seitle.

   (we got two Mark S's )

   Great Mark. I know you have not flown yet but what kind of numbers
   are you seeing so far?

   Please fly with the stock pump. We need some base line CHT data.

   I don't have any data yet on the flow rate of the RX8 water
   pump. The second gen are 30 gallons a minute.
   --
   Paul Lamar ...No rotor no motor.

Paul,
Sorry, I didn't record the cht's.  I'll note that during the next run.
As I recall, they were just slightly higher than the H2O temp.  I
suspect that will change as I load the engine more.  Lots of things to
watch during this phase.  Sure could use Tracy's data logger.

I didn't plan on making the Renesis mod until later on.  I'm just
gathering the parts for now.  You have to lock in the design somewhere
or it will never fly.  ;-)

Mark Seitle.

I have a data acq device I will loan you if you have a note book
computer. Each device records four thermocouples values directly on
the hard disk. Search Google for Omegabus D5321. These are
K thermocouples  -150 to 1250C. RS232 so you will need
a $20 RS232 to USB adaptor cable and a terminal program that
runs in the notebook computer.  I have two of these so you
can record 8 channels. All three EGT's, water temp, oil temp
and three CHT's and what ever else you need.

http://www.omega.com/