I bet yours broke at the groove.

 

I broke a stock shaft and had it replaced with billet 300m shaft. The second break was OD carrier splines were stripped out by the billet input/I never broke the billet input. Pic is OD carrier. It now has a new 300m input and OD carrier. So FLT recommend running some tm.

 

Were you locking the converter at WO? My input was literally a press fit.

 

Nope, I never lock it unless in 4th gear above 45 mph.

 

Odd. I lock mine sometimes at WO, zero tq management also. My builder said let it eat.

 

Ive had builders tell me they dont care much for the 300m shafts because the metal will twist together instead of just snapping, making dis-assembly impossible. I thought that was interesting.

A dyno is the best way to dial in timing. You will want the less amount of timing at peak torque, wherever that is. The engine is most sensitive there (peak cylinder pressure). You can have more timing on either side of peak torque.

 

My lq9, 8psi, is running about 16*