M20 Gearbox on M50b25tu in E30

[OldE30`]

Hey Guys,

So im wanting to use an m20 gearbox on my m50b25tu swap, and i've heard that if i do the gearbox will be rotated a bit or something like that, and that you need to slightly modify the transmission or crossmemeber or mounts or something like that. Sorry for the noob question but i just don't know what to do exactly. Photos also appreciated.

Thanks Guys!

[mtech325]

The g260 as found on the 325i will be rotated 10 degrees or so when bolted up to the 24v. Companies such as Condor Speed Shop and Garagistic make the modified transmission brace to accommodate for the altered transmission angle. If you use a g260, the rear most oil pan bolts will be blocked by the transmission, so the pan can't be pulled with the transmission in place.

The g240 found on the m42 powered cars will bolt up without a fuss, but it's known for being a weak transmission behind the m/s5x family of engines.

The most ideal transmission for the swap would be a ZF310/320, as it's strong and is intended for use on the e36 engine, so everything right up, including the e36's shift linkage. Since you're in Australia though, I'm not sure which transmissions are readily available.

[OldE30`]

The g260 as found on the 325i will be rotated 10 degrees or so when bolted up to the 24v. Companies such as Condor Speed Shop and Garagistic make the modified transmission brace to accommodate for the altered transmission angle. If you use a g260, the rear most oil pan bolts will be blocked by the transmission, so the pan can't be pulled with the transmission in place.

The g240 found on the m42 powered cars will bolt up without a fuss, but it's known for being a weak transmission behind the m/s5x family of engines.

The most ideal transmission for the swap would be a ZF310/320, as it's strong and is intended for use on the e36 engine, so everything right up, including the e36's shift linkage. Since you're in Australia though, I'm not sure which transmissions are readily available.

Thanks mate, the ZF310/320's are almost impossible to find around Australia (At least for me) I'll probably end up using a G260 that i'm pretty sure i have. Do you know how to tell if it is a g260 though? Is there a stamp on the trans or anything? And i'm not sure of the condition of it, is there any way to check before i bolt everything up and all that? Cheers

[mtech325]

There should be numbers that are cast into case itself. A 325 Eta g260 will have "1270" in it, while a 325i g260 should have "1346" on it. Sometimes the VIN sticker from the original car will be on the trans bell housing somewhere, which is nice because you can use a decoder which will tell you what specific car it came from as well.