I posted this on the TPI board first,but may be tranny instead.The car ildes at 500rpms normally,but when I go WOT and the overdrive kicks in and come to a stop it ildes at 1000rpms until I tap the gas a little,then drops back to 500rpms,I tried some carb cleaner on the throttle linkage,no change.any ideas?Thanks

 

Could be a weak throttle return spring... I know a guy that had problems identical to yours after installing a 383. We were wondering if the engine was actually sucking the throttle blades open. We couldn't find anything binding at all, so we put a little "helper" spring on it and have not had a problem.

 

Thanks,I just wanted to make sure it wasn't tranny related,guess I'll clean the throttle out and change that spring.

 

what many guys do is clean out there TB's with a solvent cleaner and never lubricate the throtle shaft afterwards. tryputting some light grease on both side of the shaft and see what happens.