Another challenge in installing rear diff...

[nsbone_1988_520i]

After swapping the axle flange and rear diff cover, the "newly" acquired diff still refuse to be mounted. 2 bolts at the front and rear cover bolt are nicely alligned but the middle 2 bolts are not. It misaligned about 5mm.

So am going to drill or elongated the hole further 5mm on the rear subframe, kind of like the gearbox subframe mounting can be move to front or rear. This way i can reinstall the stock rear diff if need to. I hope this will solve the problem...

What do u guys think about drilling the hole? Hopefully it wont weaken the subframe...

rahman

[632 Regal]

what middle 2 bolts are you talking about?

[nsbone_1988_520i]

what middle 2 bolts are you talking about?

Pls see the photo...

[DanH]

What is the type and year of the car that the 'new' differential was removed from?

[nsbone_1988_520i]

Dan,
That's a good question. It was taken from an unknown BMW rear subframe. It's a 3.64. Which i believe could be from e34 M20B25?

rahman

[632 Regal]

probably from something that isnt supposed to fit.

[winfred]

shouldn't hurt anything to drill them out a little

[nsbone_1988_520i]

Thanks all for encouraging support... will keep posted...

I like this place... best tru-5 series site.... kudos to all....

[nsbone_1988_520i]

OK, got the rear diff fitted this morning (in Kuala Lumpur)..(eventually).

Tested drive, it's not that bad. at 5th, 100km/h, the rpm shows 2200rpm (i expecting around 2500rpm). Felt the engine lesser stressed.

I think it's not that bad, because of the *731 cylinder head on the M20B20. Of course, B25 would be the better.

So next project, either B25 or forced induction... not too near future though.

Thanks for helps/input...

[nsbone_1988_520i]

Stock tyre size is 205/65/15. I am thinking to use 205/60/15, would this upset suspension system since now the overall diameter is shorter?

[George M]

it shouldn't affect your suspension at all...throw off the speedometer a bit...improve acceleration fractionally...and will lower the car a shade. I would stick with the stock tire size for you car. I think a better upgrade would be to add some footprint by way of a 215mm wide tire. These are heavy cars and stock come with 225mm tires with larger displacement engines. In your case however you are horsepower limited with 2.0 liter displacement and more tire width would consume more horsepower in terms of rolling resistance and increased viscous drag at highway speed.
George