T-Series TD diff change & wire wheels

[Marvin Gruber]

I've been asked by a local guy to help him put a taller geared rear end under his TD. Told him most folks use a MGA diff with TD axles to do that. He also wants wire wheels. Can he just use a MGA wire wheel diff and front hubs to do that.

Marv

 

[DNK]

Didn't we just discuss this??
or am I thinking of something else?
Wasn't it Paul who was concerned over the tall gearing in his?

 

[Marvin Gruber]

We talked about the 5 speed trans kits for a T series but don't remember anything about the diff change

 

[drooartz]

The MGA swap (gears into the T-series housing) is real common, using the 4.3 gears from the MGA. I believe some folks have used entire MGA housings as well, but I'm not at all sure about the details.

Moss sells a book by Carl Cedarstrand with all the details on doing the gear swap in a T-series axle:

https://www.mossmotors.com/Shop/ViewProducts.aspx?PlateIndexID=29463&SortOrder=1

 

[DNK]

Know this discussion was somewhere.
Know Hap was involved

 

[drooartz]

Don, you're thinking of this discussion recently:

https://www.britishcarforum.com/bcforum/u..._Wil#Post834530

 

[DNK]

Drew, Didn't Paul ask what other rear he could put in that thing instead of doing the trans?

 

[MGTF1250Dave]

Aloha Marvin,

The rear track dimension of the two cars is different. The TD/TF is alittle over 2" wider than the MGA. I beleive you will have problems with the rear spring purches on the MGA rear axle assembly not aligning with TF's springs. It may also bring the tires in very close to the inner wheel wells. The more common swap is the 4.3 ring and pinion from the MGA into the TD/TF rear end. I think if the straight rear axle swap worked, many would not to mess with the gear change.

Here is a link to pretty good article on the gear change:

https://www.ttalk.info/RearEndConversion3.pdf

If your friend is going to use the larger diameter MGA brakes on the rear axle, he should also change the front brakes also.

 

[drooartz]

Drew, Didn't Paul ask what other rear he could put in that thing instead of doing the trans?

Paul said he had a 3.9 rear end -- which would fit but he was worried it might be too tall (ratio-wise) for the engine.

 

[PAUL161]

Hi guys! To clarify, I have an early MGB banjo rear with 3.9 gears. The gears in it will fit in a TD/TF rear housing with some shim and bearing changes. If the early B rear would fit under the TF by only adjusting the perch brackets, I'd try it just for a test bed for the 3.9 ratio. If the engine handles it with no problems, I'll pull the B rear apart and install the 3.9 gears in the TF housing and appearance wise, no one will know the difference. I want to keep the car looking as original as possible.
I would not put a 3.9 rear in a TD with a 1250 engine, a 4.3 is the most desirable, as I've been told. PJ