The 8:35 final drive for the 915 gearbox
The short final drive with ratio i = 4.375 – ring and pinion as fitted to the 911 RS and RSR (Porsche reference number 915 302 911 02). Newly produced in Germany on modern gear-cutting machinery, faithful 1:1 to the original.
The quality shows on the tooth surface: ground on drive and coast side to a tolerance in the region of 0.0025 mm, not milled and lapped to a price. Every set is serial-numbered and delivered with a measurement report; the setting dimension for optimum running is etched into the pinion face. The matching high-tensile ring-gear bolt kit is included.
Gear sets and racing gearboxes
Beyond the final drive we produce:
- Gear sets in various ratios for building historic racing gearboxes
- Final drives for other gearboxes, such as the 7:31 for the Porsche 356
- Ready-to-install special gearboxes for motorsport – fully built, set up and test-bench run
- Dog-engagement layouts for pure racing use
Combined with our limited-slip differential, this adds up to a complete, homologation-ready drivetrain package from one workshop – gear cutting, differential, setup and test bench under one roof.
Setting up is part of the job
A precise gear set is worthless if backlash and contact pattern are wrong. That is why we offer installation including setup to factory specification – with original setting tools, contact-pattern check and a final test-bench run. If you install it yourself, the documented setting dimension ships with the set.
Advice by regulations
Historic motorsport means the rulebook has a say. Whether FIA Appendix K, Histo Monte or hill climb – tell us where you race, and we will tell you which ratio and setup fit.