M3 3.2 6speed gearbox to an M42

[E36-italia]

I think that I have to replace my clutch in the near future (halfway the stroke it engages, but without any feel)

but the otherday i found somebody who sells rebuilded bmw engines/gearboxxes..
He also has some M3 gearboxes in stock...

The M3 3.2 6speed is, includind 1 extra gear, a fraction shorter...which should improve acceleration
here's a ratio comparison
M3:
1 - 4.23
2 - 2.51
3 - 1.67
4 - 1.23
5 - 1.00
6 - 0.83
weight = ??

here for the M42:
1 - 3.72
2 - 2.02
3 - 1.32
4 - 1.00
5 - 0.81
Weight = ??

Not totally sure about the ratios, could not find official bmw info yet..

A shorter gearbox (and with 1 gear more) would be handy, since I live at the foot of the italian alps ;-)

now i you might guess my question... would a M3 gearbox fit to an M42?

[romkasponka]

Good idea, except first gear ratio . It could be that you will need shorter drive shaft.

[fabe]

the gearbox will fit... just that u'll need to find the right lenght of the drive shaft to mate with the longer 6 speed gearbox..

[e30boarder]

is there any other bmw 6 speed trannies that can bolt up to the m42? or is that the only one

[romkasponka]

is there any other bmw 6 speed trannies that can bolt up to the m42? or is that the only one

6 speed gearbox was fitted not only to m3 E36...

[e30boarder]

i realize that.. just wondering if there were more that could easily be adapted to work with the m42

[fabe]

The M42 has the same gearbox bellhousing bolt pattern with the M5x and S5x inlie 6 engines.. So it's compatible with a lot of gearboxes... only issue is sourcing the right length of the short shaft... unless you're adventurous enuf to cut and reweld the shaft to the required length..

[E36-italia]

The M42 has the same gearbox bellhousing bolt pattern with the M5x and S5x inlie 6 engines.. So it's compatible with a lot of gearboxes... only issue is sourcing the right length of the short shaft... unless you're adventurous enuf to cut and reweld the shaft to the required length..

judging from your words...an M3 driveshaft won't fit?
Cut&weld a driveshaft isn't really dangerous with a 140bhp engine... I don't want to do that with a 300bhp engine thou...

[nicknikolovski]

I'd get a custom driveshaft made up.

[e30boarder]

ill have to look into that. i would love to have a 6 speed in my e30

[supadave]

has anybody done this?

[gearheadE30]

I've seen a few. Mostly using 330i E46 transmissions though, iirc

[supadave]

More info please! A link or something

[fabe]

The only thing is to source for the right length drive shaft.. Maybe the shorter shaft from the E30 M20 can be used..
Length of the shifter link and the shifter holder can be modified without much hassle.

I guess for a start, measurements of the stock G240 gearbox and driveshaft (the front portion) would be good.

[KenC]

What do the e46 6speeds usually go fo?

I think the 1st gear ratio would pose some problems with my 4.45LSD haha