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MG MGB Technical - New 5-Speed Gearbox

I saw this bit in Just British that BMH are offering a new 5-Speed Gearbox. Anyone have experience with this set-up?

Larry C.
Lawrence Cordeiro

it's new. but go to
the manufacturer, and it is 20% cheaper!
Graham Moore

That is around $2600 in the use without tax.

Nice, but you can buy and rebuild an original OD for that.
Bruce Cunha

That should be in the US
Bruce Cunha

The Toyota Supra gearbox and clutch setup is highly regarded I believe, readily available, bulletproof and relatively inexpensive - at least in this country. Worth considering - but I'm not sure what diff ratio best suits the Supra conversion - someone else might be able to help. Regards, John.
J P Hall

Yep, the Toyota boxes are ok but 1st gear is fairly low compared to an all synchro B box
There are several ratio choices with the Toyota box and the one with the closest ratio gearset is great in a B but being close ratio 5th also isn't as big a step up as the other boxes
Not sure what the 5th gear ratio would be in the Mazda box either
Going to all that trouble setting up a Mazda box ,it's a wonder they didn't go for the six speed--- My young bloke has a six speed MX5 and the ratios in that box which is the same as an RX8 are perfect for going somewhere in a hurry
William Revit

Just drive your B off a pier and buy a used Miata if that sounds like a good idea to you.

"you can buy and rebuild an original OD for that"

... and have six speeds, two of them clutchless.

If you import from the UK you can get one for a tenth of that.

Muc better idea that going jap or watever. That cheap? Maybe with import fees etc 1/4 price to bring over?
Still not tables1

I installed a type 9 Ford box in my old TF1500. Worked wonderfully! In my 64 B with 5 main bearing engine I installed a 4 sync OD box last autumn. Works just as good - or even better. I have fallen in love with the flick-a-switch-and-feel-the action thing.For a B my recommendation is an OD box. Cheaper and nicer!

Jan Emil Kristoffersen

Amen to that.

Went the same way with my '67 B. The 4 synchro/OD transmission is a blast to use and it's almost bulletproof. The only repair needed, in over 30 years, was a new solenoid. A half hour job. RAY

Definitely an MGB OD box. I found a pristine unit on E-bay for US$1,000.00 and it has been a joy.

I replaced the Ribcase in the Midget with a Rivergate 5 speed conversion to obtain a OD gear, sychronized first gear and a better clutch set up. I have put 100,000 miles on the conversation but there have been many problems, especially with the clutch release bearing and the hybrid U-joint.

I recommend using an OEM solution.
Glenn Mallory

With all these type of conversions, it's always the bespoke parts that cause the issues, if not at first, but sometime down the road when they need fixing or replacing and the specialist is no longer around.
Peter Allen

I'm really glad many of you brought this up. I've long removed myself from offering, "But a B with OD gives you 6 gears"...always fell on deaf ears.

A B is a B. If you load it up with so much other brand stuff then just buy that other mark. I have close to 600K on the car. A couple of refreshes ago I renewed everything and was amazed how well the car performed when everything was at spec and not limping from budget descisions.

""But a B with OD gives you 6 gears"...always fell on deaf ears."

Funny, I've found exactly the same, even when I point out that the column manual switch anticipated paddle changes ...

"600k" I hope you mean miles and not $ ...


Yes, miles. Or there would be a lot of LBC in my tastefully appointed garage.

This thread was discussed between 20/01/2017 and 31/01/2017

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