The RX8 coils are the only coils on the market
that will fire 9000 times a minute.

The GM LS2 or LS3 or GM truck coils are only designed
to fire 3500 times a minute at the most.
Some are using them on the rotary and there is some
evidence they start having trouble around 6500 to 7000 RPM.

The reason for this  is the four stroke piston engine
fires the plug every other revolution. So 7500
RPM in a Corvette engine the plugs are only firing
3550 times a minute. A rotary fires the plug every
revolution. One reason they get so much power
for the small size of the engine.

I therefore conclude the RX8 coils are our best bet
long term. Mazda had trouble with the early versions.
Some early coils over heated and died killing the engine by
washing off the apex seal oil with raw unburnt fuel.
Poor Mazda had to increase the RX8 engine warranty to
100,000 miles or eight years.

I must say I am not surprised because Mazda was out
there on the bleeding edge with a 9000 RPM
red line and a rotary to boot. Law of unintended
consequences.

Mazda finally identified the problem and improved
the coil (we think) about 2006 to 2007.

Here is a heat sink that should add a bit of long term
reliability.

If you  are running a 2.85:1 gear box I recommend RX8 coils.

Paul Lamar

Wait a minute, 9000RPM with an 8 cylinder engine is 72,000 sparks in two
revolutions. That is 36,000 sparks by the old coils per minute. One coil per
plug with the Pertronix should work.

Dale Davies