What we do on the 901 gearbox
Complete rebuild
stripping, measuring, reconditioning and setting up the ring and pinion with original factory tooling — finished with a test-bench run and photo documentation.Limited-slip differential
available for both case variants — aluminium and magnesium — with a locking value of 25 to 75 % to suit the use.Nadella stub axle
newly made, ground and heat-treated.Uprated 7:31 final drive
ring gear and pinion newly made, all fits and gear teeth ground — in stock, as is the 1st gear 14:37.Rotation-direction change
for conversions with relocated engine (mid instead of rear), including fresh setting of the hypoid drive.Housing restoration
water blasting and magnesium pickling in our own workshop — back to the original, slightly mottled factory finish of the magnesium case.
Typical problems this solves
- Crunching gears and worn synchromesh after decades of use
- Worn bearing seats in the magnesium case
- No limited-slip differential available for historic racing
- Howling final drive from an incorrectly set contact pattern
Why inquire here
For early 911s the gearbox is often the last unsolved item of the restoration. We keep the whole chain in-house — from parts out of our own production to the set-up, test-bench-run gearbox.
In stock for the 901 gearbox
- Final drive — ground, numbered, with measurement report, ships immediately
- Homologated gear pairs including the Nürburgring ratio