Author Topic: Anotha newbie question....  (Read 2397 times)

e34biturbo

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Anotha newbie question....
« on: July 17, 2006, 02:27:31 PM »
working on my plans for my nephew......
will a M20b25 5spd tranny fir an M42?

anyone know if it is the same form and fit?  without messing with the drive shaft?

sheepdog

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Anotha newbie question....
« Reply #1 on: July 17, 2006, 08:56:52 PM »
Quote from: e34biturbo
working on my plans for my nephew......
will a M20b25 5spd tranny fir an M42?

anyone know if it is the same form and fit?  without messing with the drive shaft?

I would say no. For a few reasons. One being the transmission bolt pattern/input shafts are likely different ( I am sure the shaft is), as well as the gear ratios But I could be wrong.

The problem though is that our powerband is so different. If you want a cool swap try a Getrag 250. It will give you a close ratio trans and actually improve your 0-60. You do however need to change the rear end ratio to use it 3.79, if I remember right was about optimal.



You will have to mess with the driveshaft in almost any instance. Driveshafts however are cake.

Get your transmission in place, measure from yoke to yoke. Take the current shaft and the yokes you need to a driveshaft shop, and have them mate it all together. Expect a bill of $100-$250 (Maybe $300 due to our type of U-joint) depending on what they need to do, be it new joints, yokes, or a new shaft itself. However, you will end up with a rebuilt driveshaft when you are done.  I did this on my Chevy pickup, $205 for all  new u-joints, painted, balanced, shortened, and even a new yoke all done in 2 hours.
« Last Edit: July 17, 2006, 09:04:07 PM by sheepdog »
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Vladi

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Anotha newbie question....
« Reply #2 on: July 18, 2006, 03:12:00 AM »
My E36 engine has a Getrag 200 gearbox. It's ratios are way too short for me and the M20 flywheel doesn't fit in it. So i'm going to mount my Getrag 240 gearbox from my M40 engine+M20 clutch.:D
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