Sonnax Shift Improver Performance Packs

Sonnax shift improver performance packs combine innovative heavy-duty performance calibration for firmer shifts under load without sacrificing low-speed drivability. The precision components in these kits upgrade your transmission for maximum achievement and durability by recalibrating pressures, recalibrating shift accumulation, and including improved parts for areas that commonly wear. They are suitable for any heavy-duty application and are a critical foundation for other upgrades when modifying the transmission for high performance use. Sonnax shift improver performance packs additional facts and features: * Shorter shifts, which get progressively firmer with load * Faster pressure increase and higher overall pressure for greater clutch/band holding power * Three ultra-reliable, patented, billet pinless accumulator pistons * Unique 1-2 accumulator spring combination for shifts with character * Improved high rpm pressure * Third accumulator valve gets the 2-3 right the first time, every time * Consistent results, no guessing on calibration * Prevents worn accumulators and separator plate * Optional TCC on-off conversion prevents excess TCC pressure Show Less