Originally Posted by Jerm13

So I have a friend who's son keeps nuking motors in his SC10 RS. He has gone thru a 10.5, a 13.5 and 2 17.7's. He has been running the gearing that AE printed in the manual with 5-8 degrees bell timing. All the motors were Tekin Redline's and he has been running a tekin RS Pro Speedo.
Looking at the HotWire settings, it doesnt look to agressive. Boost is 40 degrees in 2 degree incremants with a .5 second delay. Low drag brake and moderate brake. I am trying to help him out but its been 4 motors in 2 months. The track is low to medium traction. The car handles great but just eats motors. Drivetrain is fairly smooth, slipper is working. Im at a loss and he is getting frustrated dropping coin on motors every couple of weeks.

The first 17.5 was after 5 minutes came off at 190. we dropped 2 teeth on the pinion and the second heat and main it came off at 150. 2 weeks later, same track, same setup, truck was put away and never touched, same thing. 1st heat was 200. dropped 2 more teeth and the second heat it came off at 160 but was so slow it was uncompetitive. So he put in his back up 13.5 and ran 5 minutes of practice. geared it to run 150 and he ran 2nd in the main coming off at 145. Again 2 weeks later, same'ol same'ol, same motor, 1st heat came off at 195.

I cant figure this thing out. I have had the same Tekin 17.5 motor in my truck for 2 years and its never been over 145. Im running what the book says gear wise with 10 degrees endbell timing and a fairly agressive boost timing with an RS Pro.

Any suggestions or if anyone has seen this before, chime in so we can get the problem nailed.