> The stock water-pump pulley arrangement is inappropriate for constant
    > high RPM ,the biggest drawback is the stock water pumps are
   designed to
    > operate at relatively low speeds, as a result,the standard
   impeller WILL
    > cavitate-churn coolant rather than push it through the cooling system
    > when spun by stock pulleys at high revs(5, 500and6.000rpm ).The water
    > hoses are a clue to whats going on inside the waterpump,When the
    > impellers starts to cavitate,the hoses  jump around due to turbuence
    > caused by cavitation and the resulting aerated coolant,Racing
    > beat/mazmart/mazda offer a number of pulley combinations that
   will slow
    > water-pump speed suffiiently to avoid cavitation and  also slow
   down the
    > alternator,as the alternator is overdriven by appropximately
   33%-if the
    > engine is turning at 6.000rpm the alternator is spinning at 8.000rpm,
    >
    > robert pay rotary owner from the 1970s/02/07,
    >
    > I think that is an urban myth Robert. Not what we found with
    > our water pump dyno. No cavitation at up to 7000 RPM as I recall.
    > You need a lot of water flow to cool an aircraft engine
    > as it runs 150 HP all the time. A car is lucky to see 40 HP
    > all the time. Might be true on an 11,000 RPM race car engine.
    > It will cavitate if you let the water level in the block get too
    > low.
    >
    > Paul Lamar ...No rotor no motor.

   Isn't that cavitation erosion in the two water pump pix?

   Doc Custer
   Retired Software Engineer and sometime Audiologist

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

   Yes caused by low water level in the engine.
   Note the dividing line is horizontal.

   Paul Lamar ...No rotor no motor.


Thanks paul,If some people are in need of a company that can make
eccentric shafts and grind epitrochoidal forms try www. Polgain.co.uk
<http://Polgain.co.uk>        used this company when I was replating
NSU/norton rotory housing in the 1990s  the man to talk to is adrian
Bond he has worked on rotaryengines from RR to NSU/ may not be the
cheapest but they do know what they are doing.......robert
pay

Do you know the great Emon Hurley?

I have  another question for you if you don't mind. Not
related to rotaries. Do they adjust the weight or other handicapping
methods on the British Touring Car racers? How come Seat's and
Vauxhaul's beat BMW's?