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MG MGB GT V8 Factory Originals Technical - BW T56 6 speeder

I have been offered a T56 6 speed transmission. I wondered if it would fit the Rover V8, and what mods have to be made to the tunnel. Volume IX issue 1 of the V8 newsletter covers this, but I can't get hold of it.
Already a Rover 5 spd is laying in the garage, but the T56 seems a lot stronger. Does anybody have info on this gearbox and the mating with the Rover V8?

j w mcglynn

The T56 is used here for a 5.7 ltr V8 (235 Kw and 465 Nm) so handling a 3.5 should be no problem.
Check this link:
For ratios etc.

Sorry but can't help with the mating to the 3.5 Rover engine.
Good luck, Cheers, Pete.
Peter Thomas

The trans is huge. I think it uses the same bolt pattern and input shaft set-up as the T5, but I think your biggest issue will fittign it in the car due to size.
Larry Embrey

Did some googling and found
Uh oh, this t56 looks monstrous indeed.
...maybe better to stick to LT1 from Rover Vitesse. Though the idea of a longer sixth gear is attractive. I still wonder if anyone can tell me more about fitting the T56 to an MG.

j w mcglynn

I bought a T56 from a Camaro (for $50.00) a few years back with the idea of using it behind my 215. It was huge, terribly heavy and the bolt pattern is totally different than a T5. It would have required major tunnel mods to fit and a great deal of work to mount it to the engine. In my IMHO, only the most determined need apply. I sold mine to a local Firebird owner.

I rode in a car of Glen Towery's a little over a year ago. If my memory serves me correct he was running his T56 behind a 4.2 with a 9" rear. I believe it went something like this ' OK; I'm gonna get it to 100 mph as fast as I can then shut it down.' Of course I could be mistaken 'cause the while (alleged) event took place in (what seemed like) less than 5 seconds, my head is still spinning!
Yes this has been done but with what sounded like great pain. I understand is took quite a bit of "messaging" the tranny tunnel to get this to fit. Looks like the gearing of a T56 lends itself to the mgb v8 with stock rear. If someone could just find a more sound engineering approach to fitting it.

In short:
Try contacting Glen Towery, he's been there dun that.

Get the latest Street Rodder mag. It a story on the t56 has size chart after market bell housings etc. Steve
Steve Nightingale

Glen Towery really did not have too much trouble fitting the T-56. It was detailed in the Newsletter, a copy which (I believe) can be obtained from Dan Masters ( Dan LaGrou at D & D Fabrications ( has built several custom bellhousings to fit the T56 to the Buick/Rover block. Basically he takes the rear 50%of a Camaro bellhousing and mates it to the front half of a 215 or Rover bellhousing.If you have a relatively torqey motor which does not rev very high, the extra gear could be helpful in keeping the mill in the powerband. Also, the T56 can be obtained (or retrofitted) with a .5:1 6th gear. The engine would be just ticking over at highway speeds.
The T56 is much bulkier and heavier by about 50#. I have a T56 which was scheduled for inclusion in my MGA V8 project, but as I want to keep the car near 2100#, I am opting for a T5.
Kurt Schley

I put the T56 in a chrome 72 B 5-6 years ago & it is very strong & heavy! (very over kill for a B) You have to GRIND A LOT of ribs off the case of the trans & make the trans. crossmember & internal T.O. bearing. I like the rover box, even thow I have to change the rear gear ratio & will use it till I can get a clutch fork with a slave cyl. working with a T-5 with the .63 o/d
Glenn Towery

Sounds like a big job. Just the sort of thing I seem to be constantly taking on. But I've got to admit the idea is interesting. Not that I need another gear but... (I often skip gears already. I mean, "Do I really need it?" No,... all I really -need- is 1st and 5th.)

Jim Blackwood

I am using a hydraulic clutch setup on my T5 --I used a Willwood 1 in m/c to a CNC slave cylinder mounted on the T 5 and a standard Ford clutch fork its working fine so far. I tried it with the std B m/c but it didnt have enough volume so the 1in m/c may be overkill---but I got a nice heavy clutch that I like
All the best
Gil Price

This thread was discussed between 06/08/2003 and 12/08/2003

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