Swapping in a 210mm Euro Evolution differential

[DaveAZ]

This is my first installment of my M3 Evolution differential swap.
I will be installing it into a US M3 with a manual transmission.
For those who don't know, the M3 Evolution is the European M3.

The M3 Evolution differential has a 210mm (ring gear diameter) as opposed to the US M3 188mm. The purpose of the swap is for a stronger differential that can handle more power.

Per the "Metric Mechanic" website (link below):
With a 3.46:1 gear ratio, the US 188 diff can handle 350 ft. lbs. of torque.
With a 3.46:1 gear ratio, the Evo 210 diff can handle 575 ft. lbs. of torque.
(This isn't needed for a car that puts out less than 350 ft. lbs. of torque. I plan to put out a LOT more...)

For a more in depth comparison, Check out metric mechanic's writeup:
metric mechanic Differentials

[Stück]

I hear about people busting their stock 188mm ring gear ALL THE TIME.

Except not.

[DaveAZ]

Here is where the fun starts. I heard many rumors about all sorts of special parts required to install with the Evolution differential. My being in the US with the actual parts being across the pond proved to be a problem.

I decided to try to deal specifically with England (UK) so I would not have a major language barrier. They may call a hood a "bonnet" but it is easier than translating German.

I thought people actually in Europe may be more familiar with the swap and tracking down the parts, so I found a pair of BMW forums in England.
BMW land UK
e36coupe.com

It turns out that over there it is far easier to swap out the entire subframe with everything attached than it is to just swap a differential. This makes sense for them, but not for someone who is in the US and doesn't want to ship a whole pallet overseas (which I almost did.)

I found someone in the US who does import pallets of Evolution parts to sell to the US market. Alex Lipowich in Chicago

Ebay has location specific sites including one that caters specifically to the UK. People list Evo parts on it, but shipping is expensive- price shipping first, and be sure the price you are quoted is in US dollars. Ebay UK

You can also track down dismantlers in Europe who deal specifically with BMW's to have them ship directly to you:
Euro BMW parts
moseley motorsport
Russ: M3 Spares

[Balthazarr]

Sounds like a very expensive proposition.
Seems like you have spent a lot of time on this.

I'd just be happy to know my diff won't fall apart as some member's diffs have.

[DaveAZ]

Now that I have aquired a Evolution Differential and subframe, I wanted to compare it to the US version. I still wonder if the case is the same as any used on M5, 7 series, 540, 740, 840 or 850, as they had 210mm differentials.
Here are the pictures:

Parts Schematic

Right Side.

close-up of part numbers, right side.

Left side

Close-up of part numbers, left side.

[SG_M3]

great to see this David. I've been thinking of doing the 210mm diff swap, just for fun.

I don't see why you can't run the V8 diff cars, e46 guys are running the gear sets and lsd carriers out of them. Did you check and see what would have to be done to swap the e46 vario lock and 3.62 gear set in?

[DaveAZ]

Top, in Evolution rear subframe

Bottom, in subframe

I had some pictures of the US rear subframe and the Evolution rear subframe, and they looked to have different sized openings. Once I actually had them to compare I discovered the only difference is the front bolt mount. If someone were to want to modify their US rear subframe to accomodate an Evolution differential, they would only need to cut out the flange that holds on the front subframe bolt hole and weld on a threaded sleeve to match the Evolution version.


Evo Rear Subframe, front (notice the bolt at bottom left.

US Version, for comparison.

US version, close-up of front bolt flange

Close-up of Evolution front bolt


reinforcement on Evo front bolt

Side view

Angle of front bolt compared to input flange

Evolution sitting on top of US differential from rear.

[DaveAZ]

Wow, I'm getting lots or responses to my posts as I am putting them up.

I hear about people busting their stock 188mm ring gear ALL THE TIME. Except not.

Then this isn't for you and your car that puts out less than 350 ft. lbs. of torque. Thanks for your constructive input.

great to see this David. I've been thinking of doing the 210mm diff swap, just for fun. I don't see why you can't run the V8 diff cars, e46 guys are running the gear sets and lsd carriers out of them. Did you check and see what would have to be done to swap the e46 vario lock and 3.62 gear set in?

the 210 ring & pinion on the E36 Evo M3 are the same as those in e46 m3's/euro m3's/most cars with v8's/v10's/v12's (5/6/7/8 series) except the e38/e39 and newer v8/12, which use a different gearset, per Dan at diffsonline. He mentioned it in this thread:
Euro Differential

I wouldn't suggest this unless you will put out the power to justify it. Locating the parts, paying for them, having them shipped and installing them only for a weight gain and bragging rights wouldn't make a lot of sense.

[Balthazarr]

Don't mind Stuck, Dave.
He's just the resident malcontent.

[DaveAZ]

I heard a lot of rumors of other parts I will require for this install during the process of tracking down the parts. The sway bars are the same. I think the output shafts are different, but you can pop off the ones on the Evo and use the ones from the US. You only need the differential and the subframe. If you are gutsy and want to try to modify your US subframe, you can do that and only need the differential.

There is a great differential swap writeup on this website here:
Differential swap writeup
Since I am doing the subframe as well, I will be skipping the hardest part: The Torx bolts. I will just be popping the output shafts off the US diff and putting them into the Evo diff.

Th driveshaft length had me worried.

Here is my 1995 Manual transmission (6-bolt) with the tape starting at the subframe. 4" to the end of the input flange.

Here is the Evolution, also 4", also 6 bolt. No problem.

Oddly, here is the US 4-bolt. (Not my problem, but an inch shorter)

I will be doing the actual install in a few weeks, but I wanted to get this posted for now. I have other projects to tackle first...

[Def]

350 ft-lbs of torque at the diff? I *highly* doubt that figure, unless you're calculating it to have a safety factor of about 2.

There have been some pretty high HP E36s running the stock 188mm ring gear.

My Nissan has a 200mm diff stock, and that thing has held absolutely retarded amounts of torque... the highest I've seen I think is about 600 ft-lbs on a boosted KA, not to mention all the RB26DETT swaps I've seen that make a fair bit of torque. A few go to the 230mm big diff, but I've absolutely never heard of anybody breaking one of those things, even with 800+ ft-lbs of TQ.


I think you're being overly conservative on the torque capacity of the 188mm diff. If you want the big diff, then cool, but saying your stock diff is going to blow at 350 ft-lbs is a bit of a stretch.

[328iJunkie]

Impressive. Im giving you props for doing this but yes as others have said check the FI board and you will see that people are running sick tq into their stock diffs. Alot of other stuff will break before the diff does... (halfshafts, driveshaft,etc)

[DaveAZ]

350 ft-lbs of torque at the diff? I *highly* doubt that figure, unless you're calculating it to have a safety factor of about 2.

There have been some pretty high HP E36s running the stock 188mm ring gear." "... I think you're being overly conservative on the torque capacity of the 188mm diff... (read below for further whining and criticism)

I don't mean to single you out, but it will be a while beore I continue this post and I already have multiple whiners shaking pom-poms for the wonderful 188mm differential. This thread isn't to bash the 188mm diff. Get over your issues and move on to a thread about your favorite 188mm diff that you can praise and don't bash my decision here- it is obviously too late to change my mind.

I did not come up with the numbers for what a 188mm differential could handle, I was quoting what Metric Mechanic published. (see the link in my previous post.) The link also says that the 188mm differential can handle 450 ft. lbs of torque at 2.93:1 ratio if you want to run that ratio for some reason. This still doesn't make me want one. There are options to make a 188mm differential stronger. I didn't care to explore those. If you choose to explore them or wish to appreciate them from afar like all the other "racers" behind their keyboards, that is your option.

I'm not posting this thread to argue the options that are available for the 188mm differential. If you are interested in the 210mm on an E36, read on. If not, argue elsewhere. I did not test the 188mm differential. I don't care to, that is why I am changing it. This, along with having the 1995 M3 manual with a weak differential gear ratio that is known to have bolts which fall out of its ring gear.

BMW put the 210mm on their European Evolution M3 for some reason. I selected it for use on my car which will eventually have a GM LS-1 engine with well over 400HP in it. If you don't like it, simply move on to another thread.

As far as I can tell I am the first person who is undertaking this differential swap who is willing to document it for the benefit of others. Again- if you don't like it, this thread is not for you. There are plenty of other threads on Bimmerforums to keep you interested.

[jvit27]

Still has the same shitty sway tab mounts?

[Stück]

I already have multiple whiners shaking pom-poms for the wonderful 188mm differential.

Now don't get me wrong, I'm hardly a pom pom shaker or a whiner.

Any diff can break with the right amount of abuse. I'm just pointing out the fact that the differential that is factory equipped in the US M3's is pretty much bullet proof. I can count the number of failures like you are trying to omit on one hand. Most if not all of the 500+whp cars on this forum are still pushing it through the 188 diff... and without issue.

I will thank you for the pictures and comparisons though, I was under the impression (through forum misinformation) that the subframes were "completely different" I see now thats not true, and the difference is trivial at best.

[milKt]

true,

they'll snap axles before the diff gives,
they'll mulch trannys " " " " .

[GMW364i]

The issue isnt really the differential, but the way it's mounted at the front as well as the subframe which twists up under the instant torque produced by the V8. The Evo large diff has a huge bolt on the front mount compared to the NA M3/325 etc. This is the reason as well as the larger differential that I am running one in my E36 LS1. The 188mm isn't a weak unit, the axle stubs are as are the stock M3 half shafts (same same on Evo large diff, half shafts that is)

Something else to think about is the gearing in the T56 transmission is much taller then the M3, leading to much reduced wheel torque over a turbo/supercharged M3. My car does 62mph in 1st gear, stock T56 and stock Evo M3 rear end on 265/30-19 tires.

I have produced a set of reinforcement plates for the subframe (evo and normal) after 20k miles and many trackdays and abuse. I've finally got the subframe to stay straight. These are laser cut plates and consist of 34 pieces that are welded on the subframe.

Probably don't want to keep the stock rubber mounting bushings, also much stiffer RTAB's are required if you want to prevent rear wheel hop on the car.

Paul

[millm3]

The "small" 188 Diff can handle torque >500 Nm (crank) without problems.

If there is a problem with 188 diffs it's heat .. not torque. A finned diff cover helps.

There are V8 engine E36 with the 188 diff and problems with the diff are not known. There are other weak spots on the E36 rear axle which need to be addressed, when using a high torque motor.

[DaveAZ]

I can count the number of failures you are trying to omit on one hand.

Honestly I was not concerned about the 188mm M3 differential at all.
I also am not saying that anyone needs to do this swap.
What I am doing is posting photos and information that I was unable to find when I was weighing my differential options.

Since I can't seem to control this thread from going off on a huge "Praise the 188mm diff" tangent, I will explain my reasons for this decision. (Let the drama unfold...)

When I became interested in swapping an LS-1 into an E36 I was driving a 325IS. It is the car with the open four bolt differential in my pictures. I knew I needed to upgrade the differential so I looked at my options.

I did my math. I looked at available gear ratios and their pricing. I looked at the options to strengthen the front bolt weakness. I looked at finned covers. I looked at other custom options like clutch packs and variable ramps as available here: Diffsonline I started bidding on the 188mm M3 differentials on ebay. The prices went higher than I was willing to pay.

I also did reasearch on the Evo differential and found that I could swap internals with any other 210mm diff. The gear ratio options are plentiful and inexpensive. You can plop in the E46M3 innards if you get a wild hair. I went to the EbayUK site and I landed an Evo differential which was already built to 40% lockup for under $300.00. Before the auction closed I went to UPS.com and got a price quote for shipping of 200.00. Sadly I didn't catch on that the price quoted was in UK money and I ended up paying over $400.00 to get my $300.00 purchase home. This still looked like a great deal compared to what I saw the 188mm diffs selling for.

I had located a rear subframe for my Evo diff. By the time my auction ended the subframe was already sold to someone else. It took me a year to finally find my subframe from someone willing to ship it and it wasn't inexpensive.

I knew that bolting my 210mm differential to a 325is setup would provide many other weaknesses.
I thought I solved that problem here:Ebay auction gone bad
If you read the linked thread you will see how that turned out. I think that loser is still doing business on here under a different name. One day he may grow up to be a man and be honest with people. I'll avoid him until that day.

After that experience I decided to search for an affordable M3. I looked at a bunch which were overpriced for my purpose because the owners had put a lot of upgrades into their engine compartments. (Keep in mind, I don't care about the engine.)

A few weeks ago I found and purchased a 1995 M3 that I liked and could afford. At this point I already had the Evolution Differential and rear subframe. Mine is a story of the chicken before the egg. Now if I could only convince my friends to stop calling my daytona purple M3 a "barney car" and to stop telling me they like the look of the green 325IS better...

Still has the same shitty sway tab mounts?

Yes.

Paul, thanks for your response. It has been difficult to get much input from people who have running examples of LS1 E36 M3's.

As for my comments about a much simpler kit in development, this is true. I will wait until it's ready for sale and release the details. I've learned a great deal about this combination and as Randy has said there are many improvements that can/will be made.

How is your progress going?

[porschetech]

interesting thread....i like a lot. respect to ya for doing the work and researching into this. if and when i go the vitolo route, i may consider this as another mod/upgrade to euro spec

[DaveAZ]

While reading through this I noticed that I failed to mention that the Evolution M3's have tubular half shafts that are supposedly stronger.


This was my motivation when I considered getting a pallet shipped.

I didn't buy them, I am just adding this for the sake of public awareness.

[Gizmo330iT]

I will just be popping the output shafts off the US diff and putting them into the Evo diff.

Not going to work, the output shaft splines on the 188 diff are smaller dia. than the 210 diff. You need the 210 output shafts...

[GMW364i]

While reading through this I noticed that I failed to mention that the Evolution M3's have tubular half shafts that are supposedly stronger.
(I will add a picture- I believe it is on my work computer)

This was my motivation when I considered getting a pallet shipped.

I didn't buy them, I am just adding this for the sake of public awareness.

I received the entire Evo M3 rear end, subframe, trailing arms, brakes, halfshafts when I got mine. The half shafts appeared to be the same as standard M3 units, I took mine apart and re-greased the CV joints before installation.

As for the LS1 E36 parts, I am building some parts, I will wait until I have a marketable kit before revealing the details. No point getting anyone excited until it's completely ready for market.

I can tell you that the lessons of the past are paying dividends, my setup will be significantly less expensive while improvements have been made on every part. It will be available as a very basic kit will all of the other parts as options. I recently had the entire car apart to evaluate how the conversion has been holding up for the 20k miles it's accumulated so far.

Paul

[DaveAZ]

Not going to work, the output shaft splines on the 188 diff are smaller dia. than the 210 diff. You need the 210 output shafts...

I hope I don't need the Euro half shafts... Alex in Chicago told me it will work with the US M3 output shafts and that he has done it with them before. I don't know if they bolted on the torx bolts or popped out the output flanges as I was suggesting. I just finished assembling the entire rear of the 325IS with its stock parts and I didn't compare the output flange patterns. I was able to see that the two differentials were the same width. (Russ at M3spares had me concerned about the output shaft lengths.)

I received the entire Evo M3 rear end...the half shafts appeared to be the same as standard M3 units

I was told that the earlier years had similar half shafts to ours and the later ones were the stronger tubular type. I deleted the email so don't know the exact years.

[Gizmo330iT]

I hope I don't need the Euro half shafts... Alex in Chicago told me it will work with the US M3 output shafts and that he has done it with them before. I don't know if they bolted on the torx bolts or popped out the output flanges as I was suggesting. I just finished assembling the entire rear of the 325IS with its stock parts and I didn't compare the output flange patterns. I was able to see that the two differentials were the same width. (Russ at M3spares had me concerned about the output shaft lengths.)


I was told that the earlier years had similar half shafts to ours and the later ones were the stronger tubular type. I deleted the email so don't know the exact years.

I hope you're right. When I was searching for a M3 LSD the 3.2lt one had bigger spline half shafts so I went for the 3.0lt one. Maybe the scrapyard showed me the wrong diff...