I was @ the track last weekend and broke my Spohn torque arm. I installed a new one and under acceleration no noise but when deacceleration has a slight whine. I didn't have that before. Its a 9" w/ 4:30 gears. I pulled the pinion to make sure was ok , and everything looks great. I was able to get about a half a turn on the pinion nut though, don't know if that was loose enough to cause the whine or not. trying to decide or not to drop the pig out or not. no shavings or anything in housing, oil was clean. just looking for a tip. I ran the car up to 130 mph on stands and drive shaft is true as can be aswell. thx for any input!!

 

just removed pig, everything looked fine bearings,races. lash was set @ .09 and was still there prior to removal.reset everything up and tighted lash to .07, figured would go back to straight gear oil rater than synthetic. just can't figure out why just after torque arm broke had rearend noise on coast side and never had it before, like I stated everything looks great, even checked pinion and was straight.

 

Do you have the pinion angle set the same on the new TA as you did with the Spohn TA?

Under what conditions did the TA break? Huge clutch dump?

 

same angle - 2.5, and yes, hard launch 6000 w/ 200 shot