Overdrive box.

[Blaketon]

Not sure if I have raised this before (Can’t see it in a list of my posts) but has anyone ever fitted a Triumph Spitfire type overdrive gearbox to a Minor?

I also have an MG Midget 1500, which as standard, was fitted with a BL single rail “Marina” type gearbox. I always felt the car was undergeared and I knew that Spitfires (With which the 1500 Midget shares it’s engine) were available with overdrive. I therefore obtained a reconditioned gearbox, with a new overdrive unit and modified the car to suit. As it turned out, the gearbox was clearly the same as the original, except for the overdrive on the back of it and a slightly different remote. It fitted to the original bell housing.

Since they fitted 1275 engines into Marinas and since the “Marina” gearbox is similar to the overdrive box in my Midget, it may well be possible to fit the overdrive box to the Minor. I’m thinking Marina backplate and bell housing (Clutch??) on to the back of my 1275 Midget engine (Starter is on left of Midget 1500). There is far more room under the Minor, than the Midget (The gearbox on the Midget is right up inside the tunnel). The only problem I can see it the steering rack and the bell housing fouling one another, as presumably the Marina bell housing has no cut out, like the Minor one (Or even the earlier Midget ones, which still had the same cut out).

If anyone has fitted a Triumph Spitfire 1500 overdrive box to an A Series engined Minor, I’d be interested to know how it all worked.

Someone may ask why? I must say I prefer the 4+overdrive box, to the Ford 5 speed but I don’t mind the Ford box. My mother sometimes drives the car and she really doesn’t like 5 speed gates (She has an MGB GT, with 4+overdrive). Since I have to rectify a Charles Ware 5 speed bodge, I can either rectify that or just fit my spare overdrive box.

[SteveClem]

Must say, my 5 speed Ford box conversation done by Ware's has been superb and entirely trouble free. So good that I got them to do another on my other Morris. Again,excellent. You can only say how you found things from your own experience,of course.

[Blaketon]

When the job was done, they were supposed to fit a stronger clutch, as the previous owner had not done this when he fitted the 1275 engine. The new clutch had to be hydraulically operated.

When I collected the car, the hydraulic conversion had been done (Which leaked hydraulic fluid down the bulkhead; I have since changed the fluid to a type that doesn’t damage paint). The clutch pedal fouled the back of the starter motor pinion cover, on the bell housing, which someone had clearly tried to hammer out of the way (I rectified this by filing a little off the pedal).

Worse was that sometime later (Outside the warranty period – I don’t cover a high mileage), I discovered that the stronger clutch had not been fitted (Hydraulic clutch was itemised on the bill, for the amount quoted and I took this to mean the job had been done), as it “Wouldn’t fit”. I have nursed the clutch but it is not up to the 77bhp of my engine and I have put the car away, until I can get around to correcting this fault. Wares were going to look into a solution but I think this was just a glib promise, made in the hope that the problem would go away. The only thing, that has gone away, is me, as a customer!

[charlie_morris_minor]

if you drop me a PM with your email address i can send you an article i wrote in minor matters on fitting the overdrive box to 1275 A+ engine. where abouts in south wales are you as i am down in bridgend the weekend after the bank holiday and if you are local i would happily pop over for a "chat for 10 minutes" if it would help.

[panky]

This is a project I've often thought about doing too. I love the way an OD box kicks in when the switch is flicked
PM sent

[olderisbetter]

Five speed gearboxs are usefull but i do like the overdrive button, i think it brings out the james bond in me, i have the midget 1500 gearbox but not an overdrive set up, sadly the mgb overdrive box i have is of no use to a A series set up, but i will keep an eye on this thread see if it comes up with something.

[bmcecosse]

It's SO much easier / less hassle - and much less expensive - to simply change the final drive ratio if you have the power to pull a lower ratio,

[panky]

It is indeed, fitted a 3.7 diff, and it's lovely with the 'warmed' 1098, but there will be future mods that will, hopefully, benefit from an OD box Fitted OD's to both my campers and I just love the way they operate. You get a six speed box with the OD operating on 3rd and 4th which makes motorway cruising so much more comfortable and the half ratio between 3rd and 4th is excellent on twisty bits and around town, fuel consumption figures improve quite a bit too

[Blaketon]

if you drop me a PM with your email address i can send you an article i wrote in minor matters on fitting the overdrive box to 1275 A+ engine. where abouts in south wales are you as i am down in bridgend the weekend after the bank holiday and if you are local i would happily pop over for a "chat for 10 minutes" if it would help.

Done.

[Blaketon]

It's SO much easier / less hassle - and much less expensive - to simply change the final drive ratio if you have the power to pull a lower ratio,

I had that when I had the car but I felt that closer ratios make for easier driving. As had been said, with the overdrive on 3rd & 4th, you get six gears, though OD 3rd and direct top are almost the same. I don't tend to use OD 3rd on the Midget, as with a modified engine, it does cause more strain on the OD unit (The MGB GT V8 had OD third blanked off for the same reason) but in my mother's MGB GT, I use it quite bit, if I need to change up but know I will soon have to change back down.

[charlie_morris_minor]

blaketon you forgot to include your email address in your PM..

[Blaketon]

blaketon you forgot to include your email address in your PM..

Whoops martin@harford57.freeserve.co.uk