Stiffer spring for min-max throttle levers (governor mod). Selected and tested to slow down torque control and raise the cut-off RPM.
Fits almost every throttle lever found on car pumps. Direct replacement for the full-load spring (the large spring).
- More fuel from 2500-3000 RPM up to cut-off
- Up to 6000 RPM on car pumps with no other changes
- Up to 7000 RPM with the right setup
Important: to make efficient power outside your engine's stock RPM range, you need the right injection timing and fuel supply.
Why change the spring instead of using shims?
Shims (sometimes used from the factory) and spring choice do two different jobs:
- Preload (shims) sets where governing starts: the RPM at which fuel per stroke begins to drop.
- Spring rate sets how fast fuel per stroke drops.
Fuel has to be cut back at high RPM because cylinder filling drops, which prevents smoke. A stiffer spring sharply reduces the stock governing, which is excessive for a performance build, while still keeping smoke in check.
Spring sold alone.
