'89 325i + m30 + 4hp22 build

[n3nyongmini]

Hi, thanks for doing this swap, it's the only one i can find... I'm staring mine now as well... '89 325i vert auto (dead m20)... found a running 735il (b35) and am getting the complete engine/ ecu and bell housing from it... ebay mounts from england are ordered... stahl headers for a 635 already in the garage and crossing my fingers that they fit without mods...

The only questions I have are...
-are there different models of bell housing from the m30?
-will the m20 harness work out ok with everything (other than extending injector wires)?
-any electronic hookups i need to know about on bell housing that could cause a problem?
-any other hick ups i should know about?

Other than those things, it seems like a plug n play kind of deal, right?
Thanks,
David

G:

- I dunno about different m30 bellousings, but all of the m30 w/AT bellhousings have looked the same to me.

- I am thinking yes the m20 harness woudl be A-OK; I spliced an m30 harness into my m20 harness right about a foot after it comes out of the firewall. I had to work with a cut m30 harness and only part of an m20 harness.

- No, no electronic hookups as long as you are using the 4hp22, not the 4hp22eh, which is the electronic one found on later 5 series and has its own TCU, harness and a switch or two.

- Get a new kickdown cable for your transmission as it has a seal at the end it connects to the transmission (same withe selector shaft seal - both of these are about impossible to do without dropping the AT) I got the one for the e30 but it has the wrong end on it for the m30, so I brazed on the right cable end. Or you could just get the one that has the right end - this would be from an early 5 series that used the non-electronic transmission, as the electronic doesn't have a kickdown cable. That being said, you may have to cut and braze on the end to get the length right from where it connects to the bracket. THE BRACKET: you'll need to fab one to hold the kickdown cable, unless the 735iL was early enough to use the non-electronic transmission. There are two different throttle bodies - one allows for full throttle, then a bit more for the kickdown, the other is just a plain throttle body, where if you want 100% throttle you get the kickdown. .

[n3nyongmini]

oh, i forgot... what have you done with the cooling system?
thanks again

I did the m30 version.

I've gotten it started and all seems good EXCEPT I put the wrong flex plate on. My m20 flex plate was less corroded than the m30 one I have, so I used it as it looked like it would work. I've now got a grinding starter so I'm going to try to drop the AT and swap it out IIRC I think I should be able to do it.

I'll see if I can post some pics of the kickdown cable bracket and the different throttle bodies.

OH - while you have the AT out, replace that shaft seal that blows out the A-clutch when you have a worn AT and you rev it in N or P for any length of time. I took a few pics when I did mine - I'll need to write that up. There are a couple tricks.

Looking forward to your sucess!

[G-Man the Visionary]

Thank you! Your post just boosted my confidence on this as I was starting to get worried... Haha... I will keep in touch and hopefully we can bounce ideas around to make things easier... All parts are ordered so hopefully in 2-3 weeks (work schedule pending) there will be some racket coming from the garage... Thanks again, I really appreciate your quick feedback!

[G-Man the Visionary]

Any luck with your grinding? Also, which diff do you have? Thinking about going to a 2.93 LSD since its just going to be a cruiser and dd... Lower rpm's = more mpg... BUT worried about being too slow with the auto tranny (should have plenty of tq though right???)... Before spending all the dough I figured more homework is necessary... Thanks

[n3nyongmini]

Here's a pic of the kickdown cable bracket. Needed only to grind down the spacer on the upper stud and add a stud/nut at the existing attachment point on the throttle body. It's a bit rough. I'm sure someone else could do a better job.



Here's a pic of another throttle body I had. It had the extra spring and bracket to allow for 100% throttle and THEN kickdown. I didn't use it because the barrel was very pitted. The brackets might swap over, but there are embedded "hard points" and stops in the TB casting that I don't have in the TB I used. "Next time"

[n3nyongmini]

Thank you! Your post just boosted my confidence on this as I was starting to get worried... Haha... I will keep in touch and hopefully we can bounce ideas around to make things easier... All parts are ordered so hopefully in 2-3 weeks (work schedule pending) there will be some racket coming from the garage... Thanks again, I really appreciate your quick feedback!

Thanks. It's a lot of fun. When you get the bell housing you need to get the bell housing to block bolts as well. They are different for m30 vs m20.

[n3nyongmini]

Any luck with your grinding? Also, which diff do you have? Thinking about going to a 2.93 LSD since its just going to be a cruiser and dd... Lower rpm's = more mpg... BUT worried about being too slow with the auto tranny (should have plenty of tq though right???)... Before spending all the dough I figured more homework is necessary... Thanks

I might get to it this weekend, if not it'll be next weekend.

When I get this thing rolling I'll determine what rear end works best. I have the stock 4.11 open installed but have a 4.11 LSD to put in if its the right ratio.

[G-Man the Visionary]

Hopefully he just leaves the bell housing attached for me when he pulls it so I can have the right bolts... About the diff, that seems like the best one for accel but at 70 I think the rpms would be close to 3200 or something really high like that... Have to check the conversion calculator again... I'm sure with the tq the LSD is necessary... Hahaha... I'm anxious to dig in on this job (and I'm glad you've already figured out all the kinks)!

[G-Man the Visionary]

Thanks for the pics! I'll have to wait til I have my hands on it and in possession to know exactly what you mean... Looks good though I think, as long as it works right?

[n3nyongmini]

Hopefully he just leaves the bell housing attached for me when he pulls it so I can have the right bolts

well whomever is doing will need to separate the engine from the AT to get the bellhousing off of the AT, so better to ask for them... be sure to get the flex disc too.

[G-Man the Visionary]

For sure, I'll let them know... Sometimes the junkyards here can turn into pricks and change the story on what was purchased... What fan are you running?
Thanks

[n3nyongmini]

AC aux fan, but as I mentioned, the car is still in the garage and not on the road yet .

[Doughnut]

Here's a pic of the kickdown cable bracket. Needed only to grind down the spacer on the upper stud and add a stud/nut at the existing attachment point on the throttle body. It's a bit rough. I'm sure someone else could do a better job.

Your idea of "rough," is severely impaired...

That bracket is sexy :up:

Your swap is coming along nicely, I'd love to drive an auto m30 e30!

[n3nyongmini]

Replacing the flex plate requires the engine and AT to be separated. During install, It appeared that there would be enough room to access the bell housing bolts for underneath. So I raised the motor with an engine support, pulled put the motor mounts, dropped it and the tranny down and there is plenty of room to get in there with some long wobble extensions. I left the TC on the flex plate, as it easier to separate that way, so that would also lead me to believe that a manual transmission with it's input shaft could be dropped the same way:

[G-Man the Visionary]

OK, engine is out, sitting at the yard right now... I got the radiator in the mail last night and its not fitting like everyone says... It hits the bottom mounts... I have the automatic tranny radiator if that makes a difference, and also noticed that those lines are on the opposite side as well... Did I get the wrong one? While I'm at the yard I decided to grab an e36 rack & pinion, and a trunk mount for the battery... I could not find an older 535 here for that bracket, but I can experiment when the time comes... Can I use the Old Tq converter? They don't want to give me that... Thanks!