M50 swap Gearbox Required Getrag 260

[E30nut 1]

Hi guys, I’m looking for a gearbox for my M50b25 swap into my e30, probably a getrag 260 ? Preferred in Auckland ? 

[eliongater 718]

Any particular reason you’re after a 260? The bellhousing on the M20 is different to an M50 and will be rotated by about 10 degrees, meaning your shifter and crossmember will need modification to work. 
Plus e30 tax applies to a 260 whereas an e36/46 gearbox should in theory be easier and cheaper to find. (E.g. a 220, 250, various ZF gearboxes and a 240 from an e30 with M40)

[E30nut 1]

Thanks Elijah !

No reason, ive just been suggested to use a 260 as per another mate thats done it, and yes he has mentioned the shifter issue. Th vehicle currently has an m40 in it as the moment, reckon the manual box from that would be sufficient ? and also what clutch & flywheel would i use ? Would the drive shaft & diff need to be changed too ? Also would the m40 240 match the M50b25 ? (It is out of an e34 525i)

Cheers  

Edited August 23, 2020 by E30nut

[eliongater 718]

It should be, though I’ll wait for smarter people than me to comment, I’ve not looked at this swap in a long time so am little rusty. 
Have a read of this, should help you with 99% of what you need to know:

https://www.e30zone.net/e30wiki/index.php/Engine_Swap_-_M5x

[nick496 268]

I'd say the m40 g240 is fine, unless you're wanting to drop lots of skids. In which case the recommendation would be a manual ZF box from an E36.

I'm using an M20 flywheel (which has been machined on the back to clear sump) and an OEM clutch, and it's been fine.
Driveshaft you'd be best to see how you go, measure up the length you need, try find one the right size, give up, and get it shortened.

Diff, ideally at 3.73 ratio, but others prefer more or less depending on their driving style.
Or have a flick through gearing calculators eg: https://e30goodies.com/gearing-calculator/

 

You might also want to have a flick through my thread: