cobraboy
Well-Known Member
As far as I’m aware that diff with the extra ribs on the case is a four gear diff.
It would have really woken up my car, I regret not fitting it.
Assumed output for Rover v8.
- Thread starter Oldskoolrob
- Start date
It would have really woken up my car, I regret not fitting it.
I'm not sure that it is. The plain case is 2000 3.54, the ribbed case is 2200 3.54, both 2 planet gear diffs, and the ribbed case with the strengthener clipped to the pinion shaft casing is V8, 3.08, with the 4 planet gears.
Is it possible to fit the crown and pinion from the 2200 to the 4 planet gear V8 diff or vice-versa and create a hybrid?
Yes, but It does require some machine work to fit the 2200 crownwheel to the V8 diff unit, so presumably that would apply if you wanted to do it the other way around, although I can't see why you would.
cobraboy
Well-Known Member
I’ll go look, I thought it had the strengthener clipped to it,
I’m trying to think if there is an opening to get a camera inside to check.
cobraboy
Well-Known Member
I’ll look later and look at the ratio as well.
mrtask
Well-Known Member
Much obliged sir. Which bit is the 'strengthener'? That steel(?) plate on top of the silver extension, held on by a couple of hose clamps!?!?
Tomorrow I'll have a nosy in my garage and see if my spare diff looks the same. I don't think I need a third one, but I'm sure you'll find a buyer. It's jolly nice'n'clean! Sorry to hijack your thread, OldskoolRob!
Tomorrow I'll have a nosy in my garage and see if my spare diff looks the same. I don't think I need a third one, but I'm sure you'll find a buyer. It's jolly nice'n'clean! Sorry to hijack your thread, OldskoolRob!
Yep.
The ribs on the main case just in front of the oil filler plug are just on 2200 & V8 diffs, the 2000 doesn't have them.
I think that from the factory it was more to combat vibration than for strength, so probably "strengthener" is a bit of a misnomer
The steel plate forms a very crude lamination for the aluminium alloy pinion extension case. The case being made from such material will suffer cyclic fatigue and crack when subjected to repeated flexure. The steel plate will reduce the magnitude of that flexure thereby extending the life of the case. Vibration through the drive train would be more noticeable without the plate, so in essence as Harvey surmised, it serves two purposes. By reducing flexure it also works to minimise vibration.
Ron.
Ron.
Oldskoolrob
Active Member
I can't imagine paying what you would for a Rover back-in-the-day and seeing that under it lol
mikecoombs
Active Member
That's probably why they stuck it on top where you can't see it....I've often wondered if the position of the hose clamps makes any difference. There is a video out there about the gas turbine which has a number of other plots. One of which mentions that it took the many attempts and changes to quiten the diff down. Apparently the pressed steel plate across the back finally solved the issues but I suspect when they went V8 they would have to start again due to the changes for stiffening.
Spicer as the manufacturer of the differential assembly provide a product based on specifications provided by a mechanical engineer from Rover. The engineers from Spicer will follow the specifications provided and not deviate from that. They provide a product for an agreed price as detailed within their contract. After receipt Rover are not entirely happy with the product, but Spicer have provided exactly what was asked for. So what does Rover do? To ask for an improved pinion extension case with additional ribs for stiffening is an expensive option, and as Peter no doubt correctly states, "no new money for an improved casting". So engineers being good at solving problems consider the degree of flexure that testing has revealed to be evident within the casting. One cheap and very effective way of reducing flexure whilst also reducing the resulting vibration is to provide a form of lamination. A piece of steel clamped to the pinion extension case will do the trick nicely. Its shape and thickness along with its material properties are all important. More material than necessary is waste of money, so remove what is not required meaning more pieces per sheet of unit area. I expect the location of the clamps is important else the assembly workers might well place them anywhere. Engineers will normally write an assembly specification which will stipulate the spacing and location relative to datum points for the clamps. The torque will also have been specified. In this way it is a controlled process that will deliver a required outcome.