engine and drivetrain Swapping out the auto for a 4spd how to???

[richinatlanta]

I have a '76 with an auto that I'm building and just purchased a 4spd to swap into it.  I've searched, and searched but cannot find a how to for this.  Only able to find writeups on 5sp swaps.  Can anyone send me a link to this?  I'm sure it exists somewhere.

 

Thank you

[Gordon]

Even though this write up is for a 5 speed, it's the same principle for a 4 speed.  I can't speak for the difference in length between a 4 speed and automatic driveshaft. Others on this forum can speak up on that issue.

 

http://www.lexam.net/peter/carnut/5-speed.html

 

G-Man

[Hans]

I assume you have parts from a donor car?

[richinatlanta]

I don't have a donor car, but I've acquired the parts.  Looks like I'll just go over the 5 speed writeup and take it from there.

[peterschop]

A transmission swap from auto to 4sp is basically the same as it would be to 5sp. You have to do all the same things including having a drive shaft made, put in pedal box, putting in new clutch, flywheel, clutch MC and slave.  About the only thing you won't have to do is have a 4sp shift platform shortened and maybe you can use your transmission brackets on the tunnel. It is all just as much work so my advice to you is spend a little extra money and pick a G245 transmission to put in it. You will not be sorry you did.

 

With that said, Gordon's link is a great resource.

[Henning]

Don't forget to add the guide bearing assembly in the crankshaft's rear end:

Nr. 13 - 17.

Then you will have to remove or change the wiring under the steering column. Atomics have a switch to avoid starting the engine in R-, A- or 1-,2-,3- position.

Hen

[richinatlanta]

Awesome.  Thank you!

[Hans]

I'd be inclined to find a 5 speed.Overdrive 5th makes a huge difference. A little extra money now, but you'll be kicking yourself later for doing all that work to put in a 4 speed.

[Gordon]

FYI in case you haven't seen this FAQ Tech Article

http://www.bmw2002faq.com/articles.html/_/technical-articles/engine-and-drivetrain/five-speed-conversion-r29

 

+1 on the above comments, if you are already in there, you might as well do a 5 5-speed conversion. You'll kick yourself in the butt later for not doing a 5 speed. Been there, done that and would do it again in a heartbeat. The majority of my 02's over the past 34 years have had a 5 speed conversion in them and no regrets.

 

G-Man

[jgerock]

I'm not sure if the automatic-equipped 02's had the 3rd port from the brake fluid reservoir to feed down to the clutch master and slave cylinders.

[richinatlanta]

I really need to read up on this swap and see what all will entail.  Thank you for all of the advice!

[peterschop]

I'm not sure if the automatic-equipped 02's had the 3rd port from the brake fluid reservoir to feed down to the clutch master and slave cylinders.

 

It didn't. BF reservoir has to be replaced also along with a pilot bearing in the crankshaft.

[Dabliz02]

^^^^+1  I forgot the pilot bearing when it the engine was still out of the car, did it when it was installed.  It would not spin at all.

I would also suggest rebuilding the pedal box before you pop it in.

[blackmesa533i]

It didn't. BF reservoir has to be replaced also along with a pilot bearing in the crankshaft.

I know that the reservoir is still available new from BMW with some checking up and some info from Andrew at IE but not sure what part number I'm looking for with the pilot bearing on the crank..would it be a part specifically for the 4 speed because I have the 5 speed overdrive i'm doing this upcoming week and need to figure this out. Auto to 5speed that is.

Edited February 17, 2015 by blackmesa533i

[richinatlanta]

Dang, I had no idea about the pilot bearing!  I would've completely forgotten that!