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Pandaman

M20 Swap Question

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I have been doing some reading and I think I might do the m20 swap next winter. After reading through the "6 Into 2 Does Go..." and other informational posts, I have one major question:

Will the e30 5 speed transmission work with the swap (not the trans in the awd model obviously)? The .pdf mentioned above calls for an e21 4 or 5 speed trans. I apologize if this may be a stupid question, but if I start looking for a parts car I want to get the right one. I plan on being pretty frugal with this swap when it happens!

I look forward to constructive responses and thanks for your time!

-Scott

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The G260 is too big to fit in an unmodified tunnel.

I think some have done it by cutting and welding the tunnel to make it bigger...

t

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I have heard that since my car is an automatic that the tunnel would be bigger to allow for an easier transmission swap. I'm guessing it still wouldn't fit though?

Thanks for the quick response!

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I have heard that since my car is an automatic that the tunnel would be bigger to allow for an easier transmission swap. I'm guessing it still wouldn't fit though?

Thanks for the quick response!

It still wouldn't fit, but it would be closer. The only way to fit the 260 is to either fab a new tunnel or split open the existing one and adding sheet metal.

For a 323 5-speed in ok shape expect to pay between $400-$600.

Another well-fitting option (if you want 5-speed and have the technical ability) is to use the 323 4-speed bell-housing and then use the 5-speed guts and gearing spacer from the Getrag 245 (the popular 5-speed tranny for the M10). In the picture below it's A+B.

IMG_4834-1.jpg

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I found an e21 5 speed trans for $250, but I wasn't planning on buying anything for the car until next spring. I might need to jump on it anyways...

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For a 323 5-speed in ok shape expect to pay between $400-$600.

Where? I've been scouring.....and how complicated is the bell housing swap? I have a line on a M20 242, and already have a M10 245....

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the 'bell housing' on most BMW diffs is actually the front case.

It's a pretty big job, really.

That's why some have done the sheet metal work.

Same issue with using the 'close ratio' M42/M50/52 5- speed- it's too chunky

and sits up higher.

t

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Me personaly i used the stock e30 Transmission the tunnel mod wasnt that bad .by a doner e30 use the complet drive train driveshaft inc great swap

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I have been doing some reading and I think I might do the m20 swap next winter. After reading through the "6 Into 2 Does Go..." and other informational posts, I have one major question:

Will the e30 5 speed transmission work with the swap (not the trans in the awd model obviously)? The .pdf mentioned above calls for an e21 4 or 5 speed trans. I apologize if this may be a stupid question, but if I start looking for a parts car I want to get the right one. I plan on being pretty frugal with this swap when it happens!

I look forward to constructive responses and thanks for your time!

-Scott

I used a transmission from a 1991 318is. Bolts onto the m20 and all you have to do is beat the sh%& out of the tunnel. It is a pretty tight fit, though! I have a piece of thick rubber sitting between my bell housing and the top of the tranny tunnel so there are no vibrations.

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I have a 69 2002 with an M20 engine and the E30 transmission that came with it off the 87 325i. My 2002 was an automatic and I did not cut any of the tunnel.. Yes, I did have to bang on the tunnel to get clearance. But no cutting.

If you get an E21 transmission, it has to be from the 6 cylinder Euro 323i with the M20, not from the US car with the M10. I have heard that the M42 transmission fits too but I can not confirm it.

The reason people go with the 32i E21 tranny is for the speedo drive. But those transmission are getting very hard to find. Luckily, there are other speedo solutions to address the problem. Do a search.

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Guest Anonymous

on our Chump car we used an m42 5 spd cause it is what we had lying around. Works oK but the shifter is off slightly.

a

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