high-torque starter bit the dust (long)

[lightbulb8817]

I received some feedback about the 993 tip starter likely not fitting the 915 trans so I won't be going that route.

Instead, I'm going to try the 84-89 starter (Bosch SR68X or Porsche part no. 916 604 101 01) which is rated at 1.5 kw to replace my '75 starter which I found specs saying it's rated at 0.7 kw(Bosch 003 911 023 A aka "SR17X" or Porsche part no. 916 604 101 00).

I'm thinking the Bosch SR68X starter will turn my 3.6L motor over and feel more confident the OEM gear will mesh with the ring gear better than aftermarket starters with different gears. Will provide update when I get further along.

[911pcars]

Regardless of whose replacement you choose, suggest checking/confirming the pinion gear and the engaged depth is the same as the existing starter.

[pmax]

Originally Posted by lightbulb8817

My setup is: 1975 911s, 3.6L swap, 915 trans, PMS flywheel, Sachs power clutch. New ring gear is made by Kennedy Engineering (KEP) which should have identical dimensions to factory ring gear, but with hardened steel.

You have another variable here which is the KEP ring gear. Is it identical to the factory as you assumed ?

[lightbulb8817]

Originally Posted by pmax

You have another variable here which is the KEP ring gear. Is it identical to the factory as you assumed ?

I took calipers to it and measured its dimensions, comparing it to the original 915 ring gear.

The dimensions were identical except for the thickness of the inner ring/step portion, which appears to be thicker in width by only about 0.1 mm if my memory is correct.

My original 915 ring gear should have been part no. 911-116-239-00 which was superseded by 911-116-239-04. I came across info that the later 915 ring gears (presumably -04 version) is slightly thicker. I suspect that the 0.1 mm thickness deviation in the KEP ring gear (-04 replica) against my original -00 ring gear is replicating the later -04 ring gear dimensions.

I should have recorded the measurements to report back but the motor/trans is back together now and in the car.

Hoping the later -04 ring gear and the later 84-89 starter will work just fine. It should in theory.