Offset Timing Keys sp-add This will not fit 583

This will not fit 583 fan cooled motors

Weather resistant for use in all conditions

A peak gain of 4-5 HP was seen and a huge 9-10 HP in the mid-range

Huge acceleration and track speed gains

This head has twice the cooling capacity to keep your motor running cooler to maintain horsepower by staying below the 120-degree timing curve

Offset Timing Keys sp-add This will not fit 583BMP Offset Timing Keys are offset to advance timing by slightly rotating the flywheel in various degrees. Advance your timing for more horsepower. On average it's 1 2 HP per degree. Premium gas required in most cases. 4 5 degree typically require race fuel. Easy bolt on performance! BMP Advanced Timing Keys Read full description below before purchasing Small 1. 3 Degree PN: BMP TK1 Small 4 Degree PN: BMP TK3 Large 1. 25 Degree PN: BMP TK4 Large 2. 5