When taking my engine apart this time I noticed that I was missing one of my pressure plate to flywheel locating pins in my aluminum flywheel and the other two were loose being wallowed out away from the axis of rotation despite the red locktite and hard(ish) anodized surface on the alum.

I checked my tranmission input shaft for straightness right away thinking if bent it could be forcing the clutch disc to distort the pressure plate- but the shaft is perfectly straight.

I did raise the redline from 8,500 to 9,000rpm on this last motor as I was using lighter S5 rotors and it hits that between many flat shifts and at the end of straights at Auto-x.

This motor also was running on 1 leading plug and 2 trailing plugs for several races and the combustion force imbalance caused it to loosen/loose a front stationary gear dowel pin, but I don't think this would cause a problem on the pressure plate to flywheel pins.

Is this a normal problem for high(ish) rpm rotaries or should I continue searching for another cause to this problem?

 

Ensure that the trans is *concentric* to the engine. This is relatively easily done with a TII transmission, but an N/A transmission would require disassembly of your trans. Not just "a" trans. Generally concentricity issues, if they're really bad, show up as a gritchy, more difficult 4th gear, or 4th gear popping out.

I've noted concentricity issues with various N/A transmissions. I've just lived with it, but I know that it ain't right.

What are you torquing the pressure plate bolts to?