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BMW 6 speed

Not that I'm aware of... The t56 would seem the most logical choice because the conversion parts might work, but it's huge.

I had a whole thread about is the T5 still really the best choice.
 
Already got the 'box. Under ?200 delivered. The only thing I can think of in the UK that has a T56 is an Aston Martin, and that ain't gonna be cheap!



This has the added bonus of the gear lever being in the exact same place as the M47 that came out of the car. The ratios aren't brilliant (1st could be taller), but beggars can't be choosers,
 
BB-Q said:
Already got the 'box. Under ?200 delivered. The only thing I can think of in the UK that has a T56 is an Aston Martin, and that ain't gonna be cheap!



This has the added bonus of the gear lever being in the exact same place as the M47 that came out of the car. The ratios aren't brilliant (1st could be taller), but beggars can't be choosers,
Click to expand...

Please please PLEASE document a "how to" so that the efforts can be iterated on in the community.

One of the biggest hurdles to moving the "is this REALLY the best transmission" ideas forward is people not documenting measurements or the process or what works and what doesn't.

Which box is this?
 
GS6-37BG. It's a Getrag 'box found in the BMW 130i and 330i. Officially it can take 370Nm of torque but the Swedish are reporting that it can cope with twice that. The 'box is actually designed by ZF, but is manufactured by both ZF and Getrag. The last letter of the model code is the manufacturer, so the identical ZF version would be a GS6-37BZ.

Ratios are:

1st: 4.350:1
2nd: 2.496:1
3rd: 1.665:1
4th: 1.234:1
5th: 1.000:1
6th: 0.851:1

Not the 1st gear I'd choose, but then it wasn't the price of a close ratio 'box! I've yet to discover if different gearsets are available for it.

There is a big brother to this gearbox that comes in the 3.0L diesels. It's a GS6-53DZ, and will, according to our Scandanavian friends, take over 1000Nm of torque. The only reason I didn't go for that one is that it was suggested to me that I might have to modify the tunnel to make it fit. The UK has some very harsh rules regarding modifying any part of the monocoque, and potentially losing the car's identity. It's not often enforced, but it would be just my luck to get caught, so I'm not risking it!
 
Interesting... seems like basically a crawler gear and then a 5 speed with a sportier "top gear".

What rear end is it usually paired with? Also... if the shifter position is already spot on, how are you planning to adapt it? Cut/weld bellhousings?
 
If you use a BMW box you will want a 3.15 (great) 3.31 (good) or 3.54 (not as good) rearend otherwise you will have high revs at highway speeds
 
Does anyone have any info on M3 or M5 6 speed gearboxes ? Gas ... not diesel.

These two should only have a bellhousing (and maybe shaft length) difference -M5 being more useful for us-, but i am sure that they hold lots of abuse.

Tons of M3 gearboxes are available over here, and you can even buy an SMG which with a simple mod takes a gear lever (even cheaper).
 
Great ! very interested in this - especially if it's going in that 240.
I'd looked at BMW six speeds but decided that the ratio's didn't offer any advantage over the M90 (which I already have, waiting to be installed) Ideally I'd like 1:1 as 4th gear & then two lower gears for high speed cruising. I have a 3.91:1 rear diff which gets the revs quite high on the motorway.
Did you choose it for the ratio's or for what you're putting in front of it?
Tim
 
For what I'm putting in front of it- a B5234T3 and (eventually) Holset H1C. Even if I could find a whiteblock M90 I'd be rebuilding it frequently!
 
p18002.5t said:
If you use a BMW box you will want a 3.15 (great) 3.31 (good) or 3.54 (not as good) rearend otherwise you will have high revs at highway speeds
Click to expand...

This. I've the diesel 6-speed in my m50 pwrd 245 and it works great with 3.31, but it could be better with the 3.15
 
Most of the info I have is for using one behind a redblock and even then it's spotty, mostly in regards to a clutch/flywheel combo. I don't think an adapter plate is possible hence why many have had an M46/M47 bellhousing welded to the BMW gearbox.

I'm not sure about the abundance of the T56 overseas(from the primary distribution) and if it is available it has a pretty steep buy-in by itself. Then there's the 5th & 6th gear issues among other things in the regard of the T56. As has been said, they are dimensional behemoths.

And yes, before other parties come in here I will also acknowledge that the ratios aren't the best and will likely need some rear end modification in both instances...
 
Ah, that slipped my mind, apologies. Edit from the last time I asked
towz-T said:
prices where
€2250 for the twin kit
€2480 for the triple +postage
Click to expand...

Also it's for the red pattern, white bell pattern is different
 
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It's (for me at least) not necessarily about which is the best transmission- if I had the budget it would have a sequential transmission for ?10k- it's about budget and what will hold up to the torque produced by a heavily boosted T5 engine. In this situation I have to accept that the ratios aren't the best and live with it.
 
p18002.5t said:
If you use a BMW box you will want a 3.15 (great) 3.31 (good) or 3.54 (not as good) rearend otherwise you will have high revs at highway speeds
Click to expand...

Until it (one day) gets an Explorer 8.8" it will have whatever rear end ratio a manual 1992 2.0L 240SE has :-P
 
I am putting a similar box behind a toyota v8 for my 740. The fixed bellhousing makes things a little challenging. I am making a bellhousing adapter coupled with a flywheel spacer to compensate for the extra thickness. Same strategy should work for a b230.
 
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