Using an 240 G/Box from an M40 on an M20 engine.

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SAS325i
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Fri Sep 20, 2013 9:41 pm

Hi Guy's

Thanks for all the previous help & advice....

Just to re-cap I am doing a conversion on my R/H Drive 88 model
318i M40 motor to a M20 325i.

I am trying to use my original 240 G/box of my M40 motor.
(I know its not the best option but it s my only one at present)

The M20 motor with the 318i 240 G/box is in the car and everything is working except the rear gear box mounting is not lining up.

I did have so photos send on this forum before but found out after a lot of head scrathing that they were from a mounting to work on a 240 g/box mounted to a M52 motor.

Can anyone help my with some photos or information on what mods must be done to the g/box mounting and linkages to so I can finish the job.

Cheer's

SAS325i
HairyScreech
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Sun Sep 22, 2013 12:17 pm

The 4 pot engines have a different tilt to the 6 cylinder SOHC engines.

The bell housing on a 4 pot, or an m5x series of engines is the same.
M2x and M3x series engines are the same.

If you mix and match then you have the issue of the gear box not sitting at quite the right angle, what you have is there reverse of the issue that the m5x boys have when using an m20 gearbox. Have a look in the m50/52 section and you will see what I mean.
2.8 development thread http://www.e30zone.net/modules.php?name ... c&t=170822

m3.3.1 m20 thread - now running, chip needed - any volunteers?
http://www.e30zone.net/modules.php?name ... =viewtopic&
e21jps
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Sun Oct 20, 2013 8:29 am

i think you will find m10 4cyl and m30 6cyl are the same, also m20 6cyl and m50 6cyl etc the same

Not sure about m40 but my guess is its the same as m10/m30 so not much you can do apart from find an m20 6cyl gearbox
jmc330i
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Sun Oct 20, 2013 9:37 am

e21jps wrote: Not sure about m40 but my guess is its the same as m10/m30
No, the M40 is the same bell housing bolt pattern as the M50 and M20 - the M40 box will bolt straight onto the M50, however on an M20 the box will be tilted (as Harry said, the opposite tilt of fitting an M20 box to an M50).
James
'91 325i Sport
'93 318i touring 16v
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