Racing Beat is milling rotors with an NC machine to lightened them
up. A pound lighter was mentioned. You will also save a bit of weight 
on the balance weights. I am not sure the base line weight
for this claim. Rotors earlier than 89 are heavier than 89 and later
rotors. 

BTW Bruce Turrentine tells me he redlines the 1978 and earlier 13B
engines with stock rotors to 6250 RPM so these engines are not as good
to work with the 2.85:1 PSRU ratios. Later engines can be redlined
at 7000 RPM or 7500 RPM. Better choice if you are using a 2.85:1 PSRU.

This Racing Beat rotor was developed for car racing where 8500 RPM and
above is used. I am not sure they are as light as the new RX8 rotors
however. One advantage using these rotors with a new RX8 engine would
be you could get low compression versions for turbo charging a new
side exhaust port engine. Interesting. First turbo side exhaust port RX8 
in the world anyone?

You will have to have your engine re balanced if you take advantage of these
light weight rotors. Mazdatrix has some one do it and they charge $190
for re balancing a 13B. When Perry changed to the 93 and later thrust
bearing the front balance weight also needed to be changed so he was
forced to have his engine re balanced.

John at Mazdatrix told me the price on these rotors is little more than a new
stock rotor. Probably around $400.
 
Paul Lamar
 
The AirCraft Rotary Engine NewsLetter.              Powered by Linux.

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