March Sport Compact Car mag had an article this month on
buying a used 3rd gen RX7. Price was anywhere from $11,000 to
$18,000. Not bad for a ten year old car.

Quote from the author Dan J. Gardner.
"There are only two common failures of a rotary engine-a blown
apex seal or a leaky coolant O-ring." I agree with that.

If you are overhauling your engine or you are having it overhauled make
sure you are getting teflon encapsulated O-rings. If your engine over hauler
does not know what they are or is unwilling to install them find another
engine overhauler that does. They are super cheap insurance. That goes for
the oil O-rings on the sides of the rotors as well.

If you are building the engine for turbo charger use replace the fragile stock
2 mm three piece apex seals with 3 mm two piece seals available from Hurley
Engineering. According to Dan something as simple as starving the fuel
pump can cause the engine to go lean and detonate fracturing the stock
2 mm apex seals. If at all possible use a sump tank to feed the engine
fuel as you are less likely to run it dry than if you are using just
the two wing tanks.

There was also an article on the Subaru WRX turbo. The turbo charger
itself looks suspiciously like the 89-91 2nd gen turbo which was the best
turbo Mazda ever made for aircraft use. It has a built in waste gate.
IHI VF34. There appears to be a slightly bigger turbine which is the
direction to go for aircraft use and that is the IHI VF30. If we are in
luck it will fit the stock 89-91 RX7 turbo manifold flange. This was 
enough air to get the 2.2L Soob up to 239 HP at 6800 RPM. About what 
I am looking for. A welcome development for optimizing the stock 2nd 
gen Mazda RX7 turbo set up for aircraft use. I need to research this
a bit more and find out if it will fit.

The Subaru turbo will probably be a lot more common than the 89-91 2nd 
gen Mazda RX7 Turbo II engines in coming years.
 
Paul Lamar
 
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