I'm curious to know if there are different manual transmissions that fit the different Mini engines. I want to buy a manual unit, but I want to be sure that it fits the 998cc engine I currently have. I looked on the engine block and found two sets of numbers:

The first number, cast on the block itself, toward the clutch side of the engine:

WFM1026/4NWX

And the second number, stamped on a metal plate that is riveted to the engine block, just above the alternator:

030431A

I can't seem to find any information on these numbers in my service manual. What do they represent? Also, what manual transmissions should I be looking for, assuming there is one that will work with this engine? Thanks!

- Angel Face

 

Look at the front of the trans casting on the right above the ribs. There should be a casting number. From this you can determine what type of trans & gears you have. Something like DAMXXXX or 22GXXXX.

Isn't there more info before the engine number? "XXXXX 030431A"

 

Here's some pictures I took of the two numbers I listed. I still have to get down there and find the casting number on the transmission.


Cast on the block itself...
WFM1026/4NWX


And stamped on a plate that is riveted to the block.
030431A

 

Caution
The oil passages and oil pump need to be re worked when changing from an automatic to a manual. I accidently found on WWW the quite elaborate instructions on what you have to do to the engine block and oil pump before you can safely change it to the manual transmission.

 

So I'm probably better off just locating an engine AND a transmission and swapping out the whole power unit? That is definitely some valuable info!

 

Angel,

When you get that info don't hesitate to pass it along.. I will be looking into a 1275 once I get mine back to the states. Will I need a new transmission or will the 998cc tranny suffice? If it's better in the long run to go ahead and buy new.. that's what I'll do! Any suggestions?

 

(caveat - most of my Mini information is 10+ years out of date)

Personally I would be looking at dropping in a Metro engine and box - the A+ engine is much tougher than the original A-Series engines - shift quailty on the boxes is better too, as is the potential tuning ability.

When you look for the 1275cc engine, you are looking for an MG Metro engine - this is definitely different to the Metro HL/HLS 1275cc unit, and again different to the one used in the Maestro.

However, if you are looking for a block to build from, any 1275 A+ is a very good starting point.

As far as gearboxes, again from memory, there are differences along the years. In general a gearbox from a 1275 will fit the 998, but there may be issues with it the other way around. Most important modification you can make is fitting a 'center oil pickup pip' Its realy eay to fit when the gearbox is disconnected and will prevent oil starvation when cornering hard. I am not sure about a manual box on an auto engine, I have a feeling that the crank is different, but I may be wrong (highly likely).

The differential is dead easy to replace when you have the gearbox on the bench, best to look for a limit slip one....

5spd gearboxes are a posibility, there are coversions available that use a standard gearbox housing ! Kind of expensive though.

If you are looking to stick a lot of power through the gearbox - ie over about 100hp, you really should look at straight cut cogs, maybe even have them undercut ? LSD's and straight cut boxes are hellish noisy but its all part of the charm.

The drop-gears are also available as straight cut editions, again a very good idea if you are planning big power.

The good news is that the boxes are tough, my brother still runs an engine and gearbox that I built up back in (ahem) 1986, attached to the same 1297 A+ with a 'fast road' cam and big-valve head running on a pair of split webers it put out 91hp at the front wheels originally. The engine has outlasted three shells that I am aware of, he is currently running it in an ancient Mini badged as an '850'

 

Ok, so what about driveshafts when switching transmissions? Would my automatic transmission driveshafts work with the manual gearbox? So far, I have myself as needing:

1275cc engine
Manual transmission (4-speed or 5-speed)
Clutch assembly and housing
Clutch cable
Pedal assembly
Shifter linkage
...
Driveshafts?