Taller 1st gear R7ME

Hi All,

I am putting a R7ME from a 2002 Jimny in my 1964 MG midget.
The Jimny gearbox lends itself very well for this as it's light and small and provides an overdrive 5th gear.
Only downside is the relative low geared 1st gear (3.65 vs the 3.2 on the standard MG gearbox).
The low 1st is understandable for a 4x4 (crawler gear) but not that desirable for a small sportscar.
Now I've read somewhere (but can't find where I saw it) that the first gear of an earlier small Suzuki can be fitted to the R7ME.

Can anyone point me in the right direction?

Regards,
Paul 
 

No one?

If only I'd saved the website that I found it on..

Other question.
Does anyone have the exact measurement from the bellhousing mating surface on the engine to the flywheel surface on which the clutch sits (in other words, how far does the clutch face sit into the bellhousing).

Hoping for your respons!

MGmidget wrote:

Hi All,

I am putting a R7ME from a 2002 Jimny in my 1964 MG midget.
The Jimny gearbox lends itself very well for this as it's light and small and provides an overdrive 5th gear.
Only downside is the relative low geared 1st gear (3.65 vs the 3.2 on the standard MG gearbox).
The low 1st is understandable for a 4x4 (crawler gear) but not that desirable for a small sportscar.
Now I've read somewhere (but can't find where I saw it) that the first gear of an earlier small Suzuki can be fitted to the R7ME.

Can anyone point me in the right direction?

Regards,
Paul 


 

I'm afraid we likely can't help as a taller 1st gear isn't something that we need.
You'd have to swap all the innards of the gearbox, the layshaft is one piece, so if you change 1st on the mainshaft then you have to swap the layshaft, and unless the other 3 ratios are the same, you need to swap the rest of the mainshaft gears to match it. 5th is external and slides off the mainshaft & layshaft.

It may be possible to build a hybrid gearbox from a Jimny gearbox and the gearbox out of a FWD Swift or something, but I don't know anyone who has tried.
When I had a midget the swap that was in the news was the Fiat/Lancia twincam and it's gearbox, the scrapyards were full of 124s at the time, or a Nissan/Datsun A series engine.

I think now if I was 20 something again I'd be looking at the MX5 engine & box, there are loads of terminally rusty MX5s about, but tbh at my age I'd just buy a nice Eunos and never drive it!


I actually had 2 midgets, a mark II 1100 that was absolutely faultless, but terminally rusty, and a round wheelarch mark III with a 1275 oilburner. I spent a fortune getting that rebuilt and it would still empty the sump in 250 miles, which is why I was looking at putting a Fiat engine in it.

 

Thanks for the replys all.
I understand that a taller gear is not something you guys usually look into.

Think I have found the source though:
The best 'factory' ratios I am aware of are from the 80s SJ410, which I am led to believe can be swapped into the newer and much more readily available case. This has a taller 1st and 5th with a 0.79:1 overdrive. For the effort involved I personally would be inclined to just swap the top gear, and only if you did a lot of motorway miles.
Don't know if anyone is aware of the above possibility?

Regarding an MX5 box, that is quite a big larger than the Suzuki box. the transmission tunnel on a midget is very small so an MX5 box would mean I have to cut it up which I'd rather not do.
The MX5 engine with its DOHC is also fairly tall while room under the bonnet is limited.
The R7ME has been done before with succes, thats why I intend to go that route.

Anyone any input regarding my other question:
Does anyone have the exact measurement from the bellhousing mating surface on the engine to the flywheel surface on which the clutch sits (in other words, how far does the clutch face sit into the bellhousing).

I think your going to have to mock it all on the stand to get the dimension.