-------------- Original message from Jim Sower <canarder@frontiernet.net>: --------------


> <... The reason that the water pump pulley in question is 5 inches in
> diameter is that with the reduced diameter "Racing Beat" eccentric shaft
> pulley that most of us use it is impossible use a larger pulley on the
> water pump ....
> I'm lost here ... what makes it "impossible"? Pulley interference? Not
> enough belt contact on E-shaft pulley?
> I'll have to take a closer look at my water pump ... Jim S.
>
>
> Kelly Troyer wrote:
>
> > Jim,
> > Looking into warerpump impeller design is way past my desire or
> > ability........I am sure
> > that with enough time and money a more efficient pump can be
> > had......That being said
> > I want to get into the air in this lifetime and chose to use the stock
> > pump which has been
> > proven by Tracy and many others........It has also been documented by
> > several that the
> > stock pump is on the edge of cavitation between 6500-7000 engine
> > rpm........For that
> > reason I think it would be prudent to underdrive the pump for those of
> > us using the
> > RD1C 2.85 redrive........Tracy, Ed and others are already closing in
> > on 7000 rpm in cruise
> > if they choose........Tracy runs well over 7000 rpm when
> > racing........The reason that the
> > warerpump pulley in question is 5 inches in diameter is that with the
> > reduced diameter
> > "Racing Beat" eccentric shaft pulley that most of us use it is
> > impossible use a larger
> > pulley on the waterpump....... IMHO
> > --
> > Kelly Troyer
> > Dyke Delta/13B/RD1C/EC2