Sometines the apparantly simplest things are the most difficult. I have a UN1 transaxle I plan to turn upside down, with the diff reversed and mate it to my rover engine.

Reason is to get the engine/transmission as low as possible and still keep reasonable drive shaft angles.

Problem is the flywheel is now the lowest part and I need a smaller diameter flywheel something around 240 to 280mm.

First thoughts were simple! I still had the flexiplate from the original engine, turn it down and bolt/weld on a smaller ring gear with the same tooth form and remount the existing starter motor somehow. Multiplate 7.5" clutches are available at not too bad a cost

First problem the toothform is wierd - are there different standards for these things I wonder - perhaps I should get a ring gear and a matching starter?

Next difficulty is finding something suitable - another forum suggested Renault/peugeot diesel starters but I'm blessed if I can find details of diameters etc. Another suggestion was porsche 944 as they are cheap (so he reckoned!!!!!) and the starter turns the other way so I can mount it on the gearbox side of the bellhousing.

Any suggestions?

Cheers

David

Many of the starter motor suppliers (Bosch, Denso, etc.) have their own preferences in terms of ring gear tooth geometry. Hence you need to figure out which tooth geometry that suits the pinion of the starter motor.

You also need to consider cranking speed if you change the diameter of the ring gear. Since you are planning to reduce the ring gear diameter you need to make sure that the starter motor is up to the job (smaller ring gear diameter = higher load on the starter motor).

Be careful if you have an engine with a relatively modern EMS system as fuel injection only will occur above a certain cranking speed.