"Cleanest/Drop in" M20?

[Seth Horwitz]

I know that this mod has been done to death, and have searched a lot, but I'm in a pretty unique situation, and apologize. Put simply, what's the cleanest drop in of an M20, and what impact does that have on the EXISTING transmission mounting? (I should ask about hacking to the front sheet metal, I suppose, but I'm not there yet.) I'm not looking to start anything between any vendors or users, (but feel free to PM me), and just want to know what can be achieved. To be SUPER brief, I need an automatic in this 2002, I know that the 3-speed auto is unlikely to do it for me (meaning I'll shortly go for a 1985 318 ZF 4HP22 as I've seen done ONCE before in my searching which seems to fit on a stock M10), and expect that I'll probably get bored with that and go with an M20 instead of doing much on the M10. Any help as to what caused how much movement, or pics, would be super appreciated. Any suggestion as to another (BMW) power train that could work would be appreciated, though I think this is it for anything resembling cost-efficient. (I know that's a relative term, as right now I'm willing to fly someone in to get it done right.) Thank you much. 

     Seth

[AceAndrew]

In regards to the transmission tunnel, the cleanest drop-in M20 would consist of a Getrag 245 5-speed from an E21 323i (or 320/6).  This would require hammering of the transmission tunnel, and repositioning the shift lever hole rearward 2"-2.5" (or running a super-short selector rod).  The transmission mounts would be cut off and repositioned down the tunnel.

 

However, you are doing an automatic, and that throws all the above out of the window.  I don't know of anyone who has done an M20 swap with an automatic.

[Seth Horwitz]

7 hours ago, AceAndrew said:

However, you are doing an automatic, and that throws all the above out of the window.  I don't know of anyone who has done an M20 swap with an automatic.

 

Bingo. I don’t make things easy, unfortunately. (Sometimes my fault, sometimes not. In this case, shockingly, not.) I’ve been following your old posts, by the way. Beautiful job. 

 

Unfortunately, I’m not sure there’s a shop that has done any sort of fast auto without throwing all of the shop’s resources at it. If I owned a shop, I’d do a show piece, but that seems silly for a personal toy. Thank you for your help, Andrew. 

[evil02]

Why not a M42 with an auto trans? I'm sure a competent shop can do that swap.

[AceAndrew]

3 hours ago, Seth Horwitz said:

 

Bingo. I don’t make things easy, unfortunately. (Sometimes my fault, sometimes not. In this case, shockingly, not.) I’ve been following your old posts, by the way. Beautiful job. 

 

Unfortunately, I’m not sure there’s a shop that has done any sort of fast auto without throwing all of the shop’s resources at it. If I owned a shop, I’d do a show piece, but that seems silly for a personal toy. Thank you for your help, Andrew. 

 

Happy to help.  I got word from a friend this morning that one of the shops down here has done it.  Go figure!

 

Thank you for the kind words on the project.... Thinking more about the auto, the shift arm is on the right so the transmission tunnel would need some decent fab work in that area.  You may actually be able to shorten the linkage and run the lever through the stock hole in the body.

 

It would be a big commitment by you and the shop, very much a relational project.  You can do this, just go in with your eyes wide open.  If you'd like references, PM me.
 

[tonybeemer]

Buy an automatic Honda 

[Son of Marty]

The 02's that came with a auto trans have a deeper tunnel in the bell housing area and you'll probably have to add some metal just behind the firewall to fit a auto bellhousing not a huge deal but it will need to be done.

[Seth Horwitz]

1 hour ago, tonybeemer said:

Buy an automatic Honda 

 You seem like a great guy who I can’t wait to engage with even more. I’ve spent hours going through search to avoid asking common questions like a rookie, and merely hit you with the implied ask of not taking your own time to type a smart-guy answer. Good on you. Luckily, I’ve been on enthusiast boards since A4.org in the late ‘90s, so I’ve seen your type and have no issue dealing with you. I hope that other newbies aren’t scared away by your ilk. Thanks for being helpful to someone who is both a BMW enthusiast and has a medical need for an auto tranny. You’re a gem. (Based solely on this post. I don’t know what else you’ve done.)

 

To you other guys, I truly am grateful. I have a bit more research to do. This clearly won’t be drop in, but I’ll figure it out and make things known. Thanks again. 

     Seth

[tonybeemer]

Hahah just having fun .. no need to get upset .. if your in la hit me up I’ll give a ride in my 02... ??

[Seth Horwitz]

3 minutes ago, tonybeemer said:

Hahah just having fun .. no need to get upset .. if your in la hit me up I’ll give a ride in my 02... ??

 

No harm done. I'll take you up on it in the event that I am. 

     Seth

[tonybeemer]

For sure let me know if you’re around the la area ... you might like the ride along 

[irdave]

17 hours ago, tonybeemer said:

Buy an automatic Honda 

 

Ooooo... K20 / 24 swap.  Now we're talking!  Still don't know that it solves the auto-box problem, but it sure solves the easy, all day 200hp problem...  (Don't get me wrong, HRC can suck it, but Honda does make nice engines.)

[dasfrogger]

What are you looking to get out of the car?

 

I've got an 73 Automatic, everything stock. the 3hp22 gets a bad rap, but most people who slam them haven't driven one. It's a fine transmission, especially when it's in good working order. I'm currently restoring the 73 and the m10 and auto box will go back in it. Everyone that has ever driven, ridden, or followed the car has been surprised. Is the auto transmission as engaging as a manual transmission? No. But the 2002 driving experience isn't all about the transmission choice.

 

Have you driven a stock automatic 2002? If not definitely get some seat time before you take the plunge and make the commitment to doing a swap - i think you'll be surprised.

 

Good luck on your journey! if you need anything don't hesitate to PM.

Edited December 12, 2018 by dasfrogger

[Seth Horwitz]

24 minutes ago, dasfrogger said:

What are you looking to get out of the car?

 

I've got an 73 Automatic, everything stock. the 3hp22 gets a bad rap, but most people who slam them haven't driven one. It's a fine transmission, especially when it's in good working order. I'm currently restoring the 73 and the m10 and auto box will go back in it. Everyone that has ever driven, ridden, or followed the car has been surprised. Is the auto transmission as engaging as a manual transmission? No. But the 2002 driving experience isn't all about the transmission choice.

 

Have you driven a stock automatic 2002? If not definitely get some seat time before you take the plunge and make the commitment to doing a swap - i think you'll be surprised.

 

Good luck on your journey! if you need anything don't hesitate to PM.

 

Thanks for the heads up. My gut feeling tells me that I'll be missing a gear, though. (Regardless of engine, at first.) Trannies are obviously a trade-off between acceleration and top speed, so an extra gear makes the trade off just a little bit smaller. I won't be doing 140 in a 2002, and won't be racing kids at stop lights, either. If I can have a car that is a bunch of fun on the side roads, with the added bonus of a gear that can easily keep up with highway traffic (even if I need a custom ratio), I think that'd be great. For that reason, I would like to buy a 3-speed and play around a bit, as you suggest. There have been a few California cars that I would've bought straight off of eBay to do just that, but I'm concerned of rust from a few thousand miles away with a couple of pictures. I'd gladly send a truck and a check for the right car, but some of these jokers won't even respond to a question. Alas, I move on. Thanks for the heads up. 

     Seth

[dasfrogger]

32 minutes ago, Seth Horwitz said:

If I can have a car that is a bunch of fun on the side roads, with the added bonus of a gear that can easily keep up with highway traffic (even if I need a custom ratio), I think that'd be great.

 

The stock auto trans can do that, no problem. I've made a 600 mile trip in a day with mine, sings at 4-4.5k RPM on the highway and loves it. My car has a 3.64 rear gear set (stock IIRC for an auto). I really think you'll be pleasantly surprised if you can find a car to try out.

 

I totally understand about being wary or rust. It's worth waiting and finding the right car. I hope you can find a legit seller that isn't afraid to answer questions.

 

Best of luck!