My M20 Swap

[Deutschman]

I am using all the parts from the 2002 diff, besides the actual LSD unit from the small case e30 diff. So the ring and pinion gears, pinion shaft, and out put shafts/flanges are all from the 2002 diff. Basically all I did in the end was take out the 2002 diff pumpkin, then swapped the ring gear from it onto the e30 LSD unit, and installed the LSD unit into the 2002 diff case. The bearing are the same exact size on both the 2002 and e30 diff so there are no problems there. Ones you swap the ring gears out everything in the case fits together perfectly. I also found that the e30 LSD unit does not protrude from the case any further then the 2002 unit did so there is no need at all for a spacer between the case and the cover.

As soon as I order my seals and bearings from Blunt, and finish final assembly I will do a complete write up with pictures and post it up.

[Deutschman]

I am really sorry if my descriptions are not clear enough. I have a hard time remembering all the proper names for the parts, and to be truthful, I do not know what the actual technical name for the whole diff unit (the whole rotating assembly w/ ring gear) actually is. I tried to look up all the parts names in my shop manual but all it tells you how to do is replace the seals, so no help there.

[Tommy]

I don't know the correct english terms myself either. Only thing that's not clear to me is which parts you had in when it didn't fit together? That's what I'm interested.

Tommy

[Fishhead]

I don't know the correct english terms myself either. Only thing that's not clear to me is which parts you had in when it didn't fit together? That's what I'm interested.

Tommy

He had the 2002 pinion gear (the one that bolts to the drive shaft) and the E30 ring gear (on the E30 LSD) that didnt fit.

When the 2002 ring gear was put on the E30 LSD unit, then it fit.

There are 2 differnt styles of gears for the BMW's

http://www.bmw2002faq.com/component/option,com_forum/Itemid,57/page,viewtopic/t,331875/highlight,lsd/

If you look at the E30 ring gear in this post, the gear face of it looks flat in comparison to the 2002 ring gear. The 2 mis-matched gear styles wouldnt "mesh" together completely.

Here's a link on how to put the E36 168mm small case LSD into a E21 case(I would imagine the 2002 would be very simular)

http://forums.bimmerforums.com/forum/showthread.php?t=1565138

It's interesting to find out that all the stuff that was needed (according to the Quaife website) wasnt needed for the swap.

[Deutschman]

Yep. You broke it down very nicely!

Thats exactly it.

How ever this is done and set yet. Quaife might be on to something when it comes to the snap-in type output flanges. The e30 LSD unit has small snap in rings the retain the out put flanges. On the 2002 diff unit there are retaining circlips on the ends of the out put flanges that keep the flanges in place.

The thing is ones the output flanges are in the diff will they even want to come out? They fit in there really tight! I would also thing that there would be no room for them to come out because they are held in by the half shafts and control arms.

As I said this is still a work in progress and is not done.

[Deutschman]

I got my M30 AFM today because race car...

[eurotrash]

Yep. You broke it down very nicely!

Thats exactly it.

How ever this is done and set yet. Quaife might be on to something when it comes to the snap-in type output flanges. The e30 LSD unit has small snap in rings the retain the out put flanges. On the 2002 diff unit there are retaining circlips on the ends of the out put flanges that keep the flanges in place.

The thing is ones the output flanges are in the diff will they even want to come out? They fit in there really tight! I would also thing that there would be no room for them to come out because they are held in by the half shafts and control arms.

As I said this is still a work in progress and is not done.

You're right. They aren't going any where. I believe that the snap rings were mostly to aide in assembly..

I have the 2002 flanges that are end clipped, sans the clips, in an e21 diff. Which, like the e30 piece used the grooved shafts naturally. And as long as you have the more cupped variety (from a '76), its the same as having a set of the $80 IE spacers in there.

I had originally installed the diff with the less 'cupped' shafts, and the only time the shorter shaft came into play was when the rear of the car was jacked up and the suspension hung at full extension for a while. At this point, one of the shafts did manage to come out just far enough to disengage. But it slipped right back in.

In these pics you can see the difference. It looks like yours are the cupped variety, maybe.

Short version:

Cupped version:

[Deutschman]

Sweet! Good info! Thanks.

[Deutschman]

[Deutschman]

Did a few things today. Cleaned a few intake parts and painted the manifolds. Base coat of VHT super high temp primer, and then VHT super high temp aluminum. Sadly I must have ether put the paint on to fast, or just not waited long enough for them to dry, because when I picked them up to move them to a safe shelf the paint got fucked up. I guess I will just let them cure for a few weeks, and then give them a quick light sand to take the smudges out and a coat of paint.

Next weekend (my one day off every week ) I plan on switching the electronics from the m20 MAF to the m30 MAF.

I need to make a BLUNT order.

[Deutschman]

Got a few small things done today. I got the electronics switched over from my m20 AFM to my m30 AFM. Then I gave it a quick clean.

Also got my diff out put shaft flanges cleaned up with some new seals.

Some more random parts. I also sent my 19# injectors out to OKinjectors to get cleaned and re-manufactured.

Got my vacuum hoses in.

And the bearings I need to finish the diff, with some exhaust studs from Mr. Blunt.

4x 2.5" exhaust band clamps, 1x exhaust welding band clamp, 1x Y-pipe (2"in 2.5" out), 1x Cherry Bomb glass pack (for resonator).

Just waiting on my 2.5" mandrel bent stainless tubing kit from mandrel-bends.com.

Sadly I ordered lap joint clamps. I should have gotten but joint clamps. Good thing they are only $7 each!

Got some stuff done today.

I scored a Milwaukee Metal Chop Saw off C-list last night for $45 for my exhaust and other welding projects. I am super stoked on it! I am also getting a Hobart 140 from my girl for Xmas.

I still want to find a small counter top bench press, and a bench vise.

I also finished the diff today.

I got the old worn bearing seats cut out.

And the new ones installed.

Then I just threw everything together.

And now I have a limited slip 3.64:1 early e21 diff (using the LS mechanism from an e30 small case 4.10 diff). I will need 8mm bolts but no spacers for this diff to bolt into my car!

[White.Lightning]

The head work looks nice, and the engine almost looks too pretty to fire it up. J/k!

[Deutschman]

Thanks!

A few things have happened sins my last post.

I tend not to post here much because I feel no one reads it. The thread never gets bumped up to the top when I post new stuff and it is hard for people to find.

Oooooh! 2.5" stainless steel exhaust tubing!

http://www.mandrel-bends.com/catalog/?gclid=CNnEm_T7vqwCFQZbhwodg0uJqQ good prices!

Got my injectors back from Okinjectors. I am happy about the flow rate increase.

Okinjectors is great as well! They are part of the same company as High Performance Store Inc. (silicone hoses provider). They were very fast returning all my emails and phone calls, and refunded me my money very quickly when I accidentally payed them twice with Paypal (F**K PAYPAL!). Very happy with them and their work!

These are 19lb injectors. It was $139 for six injectors with new seals, o-rings, and pintle caps. They come with a one year warranty as well.

I was installing my fuel rail today and decided to have some fun with my iPhone 4S and some photo apps.

I even painted the fuel injector retaining clips!

And started putting the gauge cluster together. Used a bunch of JB Weld, and epoxy.

Sadly the primer did not want to work with the paint that was already on the aluminum .

I took the aluminum down to metal again an reprimed it with self etching primer. Then I got it paired black and put the gauges in.

I'm happy with it!

[GoFaSSter]

GAuge cluster looks great. I really like the clean job you did.

[Meintii]

Very cool! but .. the speedo only goes to 120?!? you'll need abit more than that!