JW Performance Transmission Shift Improver Kits

Increase the Performance of Your Transmission

These shift improver kits increase the performance of automatic Powerglide/TH350/TH400 transmissions. They are cost effective and include necessary valve body plates, as well as gaskets and complete instructions. Available in your choice of Street/Strip and Heavy Duty kits.

Street/Strip: For hot rod applications - substantially increases line pressure, and removes the delay out of the shift.

Heavy Duty: For towing or RV applications - removes the delay out of the shift and not quite as harsh as the street/strip version.