e9x M3 front and rear end swap

[houtan]

I feel you. It's a lot of work to document. Please give us updates when you have time. Awesome thread and looking forward to your progress. Good luck.

[drwillb]

Dropped off fenders and bumper for paint a couple of days ago. They'll be ready this Friday then I have next weeks off for Easter break. I figure 2 days will get the entire front end done.

Looking for a driveshaft shop in north Jersey. I've got someone in Clifton, but they weren't very convincing over the phone. They want to look at the driveshaft first since, of course, BMWs are not like American cars. They're more complicated.

[drwillb]

Getting ready....

Sorted out the garage. The couch and chair are old pieces we replaced in the living room. I'll put those out in the driveway, under a pop-up, while I'm working. There will be some friends dropping by.

Bodywork will be ready this Friday.

I forgot this was Easter weekend so I won't be able to start the job until Tuesday but I'm off all next week.

Getting psyched......

[drwillb]

Went to pick up my finished 1M panels. The color looked good but there were some debris imperfections on the fenders. The shop owner looked at and said "I thought these were for a track car?" Then he said he'd buff them out.

Got my fingers crossed but to me that's a re-spray. You can't buff that out. I know they have a spray and bake booth so makes you wonder how clean they keep it.

Anyway, $200 per panel is very cheap around here. The dealer owned body shop was about $450 per panel and I got other quotes in between.

[drwillb]

Still having trouble getting started but I did pick up the painted parts and managed to get a couple of basics done: put the Vorschlag plates on the front struts and got the hubs onto the hub carriers.

Of course, got stuff to do early tomorrow but all the front end bits should be a simple swap. The only possible hangup I see is getting the tie rod ball joints off. First thing will be rebuild the brake calipers.

Sunday will be bodywork day. I think a full day should be enough time.

[houtan]

Looks like a lot of work, but it's worth it!

[drwillb]

Finally got to it.

Did all the front suspension and brakes. Took about 12 hours, including lunch brake and a couple of visits from friends that wanted to see the action.

My approach was to remove calipers and leave them hanging til the very end and then replace the brake lines and bolt up my rebuilt M3 calipers. I disconnected the tie rods from the hubs, control arms from the subframe, ABS sensors, and sway bar links then dropped the strut with the brake rotor and hub carrier attached. I figured that would save some time.

Prior to lifting the car I put a piece of tape on each fender and made an arbitrary mark on the tape. With the car still on the ground, I measured from the center of the roundel to the mark on the tape. This was my reference for ride height so I could then jack up the hub and torque down the control arms.

Everything went together pretty smoothly and I sorted parts out according to left and right sides and also put all nuts and bolts together with each part. I did this the night before I started working on the car and it definitely helped save time.

I did lose a lot of time trying to get the new dust boots on the brake pistons. I struggled for a couple of hours on the night before work day. The problem is that the boot has a metal ring imbedded in the rubber and this is supposed to be a press fit over a flange on the caliper body. Lots of cursing went on over this. Funny, but I went to bed and the minute my head hit the pillow I came up with the solution. I used my son's 3-D printer to make a sleeve for pressing in the dust boot. Not a lot of space to work in, either, since there's only about a 3mm slot on the back area of the boot seat to get any tool into. This thing worked perfectly! I even spent a good hour and a half on the internet trying to find solutions but couldn't find any.

Brakes: M3 brakes are ///Massive. The rotors are very cool, too: floating, slotted, cross-drilled, big, and factory part. I've got a neat solution for brake cooling that I'll post once I get there.

Hot tip: when replacing the brake lines w/SS lines, I replaced the fluid reservoir cap with my brake bleeder adapter cap (you can also take the stock cap off and stretch a rubber glove over the top and snug it down with a tight fitting rubber band). Doing this prevents brake fluid from flowing out of the lines after opened. Also, do yourself a favor and buy the proper flare nut wrenches: 11mm and 14mm.

Sway bar: strange thing is that the M3 coupe sway bar is 26.5 mm diameter but if you measure the 135 MSport sway bar, it is also 26.5 mm in diameter. They are basically identical except for the center section of the 135 bar has a smaller diameter for a few inches. I guess that the overall measure/effect of the sway bar is only as good as the smallest diameter at any given point on the bar. You engineering types can chime in. Another note: the bushings for the M bar are a really tight squeeze. They appear to be a few mm too small.

One final note: I did research on all this for a few months as I rounded up parts but I didn't come across one minor detail that bit me in the but at the very last moment. My plan was to do mechanicals and body all in the same weekend but, as usual, I had all kinds of delays last week (even though I was on vacation and thought I'd have more than enough time to get all this done) and I was only able to do the mechanicals. Anyway, it turns out that an 18" 261 wheel will not fit over 1M/M3 brakes. That fine point did not become evident until 8pm Sunday night. Also, my new Apex wheels for 1M fender fitment will, obviously, not work. Ouch.

I'll be putting in some hours each night, after work this week in order to get things finished.

[drwillb]

Here's my dust boot tool for pressing them in. I had to make a notch in the back to clear the body of the caliper.

[John_01]

I think its fairly common to use 18" wheels on M3s. Why do you think the Apex wheels will not fit?

[drwillb]

The stock 261 18" do not clear the caliper.

I have Apex ARC 8 18 x 9.5 et 22 ready to go but I need to get the 1M fenders on in order to have the needed space. I know these will clear the M3 caliper.

[drwillb]

PROGRESS!!

This took a lot more time than I expected but it's just nuts and bolts stuff thanks to using only factory parts.

I'll update the OP with some of my findings. Just some things that I did a little different than those who have preceded me. I'm not trying to re-invent the wheel since I'm really just following their lead.

[Yeineken]

Looking great so far!

[houtan]

Originally Posted by Yeineken

Looking great so far!

+1. Great job!!

[drwillb]

She's come a long way but now we are in full house makeover mode so my garage has been completely hijacked and I won't get it back for another week. I'm very nervous about my June 9, Watkins Glen deadline now. I'm confident I can get the rear end bolted up in one weekend but I need to find a driveline shop in north Jersey for the driveshaft work.

Here are some updates:

1. I did the suspension then the bodywork. Turns out this was the wrong order. If I had done the bodywork on the first weekend then the stock wheels would have fit over the stock brakes and inside the 1M fender. By doing the suspension first, the stock wheel did not fit over the M3 caliper and the APEX wheel did not fit inside the stock fender. I wound up renting a car for a week so I could get around.

2. Another reason for doing bodywork first. The 1M fender liners need to be fitted before the struts go in place. I did the struts first so I then had to cut a slit into the liners to get them around the struts. You can barely notice it once they are in place, but I hate cutting up brand new parts.

3. As posted above, the M3 caliper dust boots are a total bitch without a special tool. I'd say they're nearly impossible without it.

4. I elected to go without headlight washers. I've always questioned their value and it just uses up the washer fluid more quickly. As per TUN3D's build, I looked for the plastic plug for the washer pump at Lowe's and Home Depot but couldn't find one. I remembered I had some black RTV silicone so I went about blocking the washer pump filter with this then let it set 48 hours.

5. I put in fresh M3 tie rods, inner and outer. First, the stock tie rods are long enough to work with the longer M3 control arms. There's plenty of meat left on the threaded end once you wind them out to reset the toe. The M3 rods are definitely longer and I was worried I wouldn't be able to get correct toe before running out of rod. Below is a picture under the car with toe set to zero. Overall, the tie rod ends on the M3 parts do look a little more robust.

6. While torquing down the strut top nuts, one of the studs broke its weld and became a spinner. This was on my brand new Vorshlag camber plates. I kinda knew what I was going to run into in trying to fix this but it was actually a much bigger pain in the ass than I expected. Vorshlag customer support was excellent. I had a replacement part in 2 or 3 days. I should have waited for the weekend but I had an alignment appointment set up at the shop I use, so I decided to tackle the project on a Tuesday night, at 9pm. Bad move. Because the one studs was spinning, I couldn't remove one of the nuts holding the strut in place. This meant I had to disassemble the strut inside the wheel well to then gain access to the underside of the studs and then grind off the head of the offender. Then, reassemble the strut and bolt everything backup. Piece of cake. Done at 1:30 am. It should have been much easier and quicker but the allen socket at the top of the stud had gotten fouled when the stud was welded to it's bracket. I tried all my metric and SAE allen wrenches but none worked. I also tried vise grips on the stud but that didn't hold. Time to cut.

That's it for now

[drwillb]

The floors are done and I've got my garage back but now I only have 9 days left before I leave for Watkins Glen. I'm ready to do the rear end swap but the shop I had lined up started getting flaky and asking for all sorts of measurements and then the whole cut and weld thing became a problem.

Seems to me that the front half should not get any changes at all and the rear half (M3 donor) just gets shortened to whatever then new overall length is. Easy Peasy.

If anyone has a lead on a NJ shop that would be ideal.

Plan B is to have a 1 piece shaft made up but I have not heard anyone give feedback on those. I know these are used on the track but how do they stand up with daily use and salty roads, etc.

Plan C is to have a 135 LSD made up, keep the stock driveshaft, get the HPA 1M rear shock adapters so I can run 1M suspension all around, do the control arm and bushing upgrade, and deal with the above later.

Plan D is run the stock open diff on the track, get the HPA 1M rear shock adapters so I can run 1M suspension all around, do the control arm and bushing upgrade, and deal with the above later.

Plan E: buy a 1M driveshaft since this is made to fit an M3 diff with the N55 tranny. My 2012 135i with M3 rear subframe will match those specs.

Being a "frequent flyer" at my local dealer, I've earned a healthy discount tier. By the time I add up shipping costs, aggravation, parts, and labor in order to make a Frankenshaft I'll be close in cost to a brand new, shiny 1M driveshaft.

I'm off to the dealer this morning.

[Yeineken]

Hoping the OEM 1M drive shaft gives you no problems.

It's a shame you don't have more time. I can't remember the name off the top of my head but you could look into a custom carbon fiber drive shaft down the road. This is the route I probably will have to go when I do my rear end.

[drwillb]

1M driveshaft has been ordered.

In case anyone is on the fence about doing this, the parts people told me that there were zero of these in the US and only 2 in Germany.......make that 1, now.

Delivery will not be in time for my track event but at least I've got one less thing to think about.

[drwillb]

Last weekend I finally got my garage back from the contractors working on the house and I immediately got to work tearing down the rest of the salvaged M3 subframe. I had already found a cracked subframe bushing (How on earth do you manage to do that. Must have been a pretty big hit) back in Feb, but now I found a bunch more stuff: bent trailing arm, adjustment tabs broken off one of the lower camber arms, badly bent bolt on one of the control arms, etc.

This was enough to make my blood boil. I shot off a long text with pictures to the guys that sold me the parts, asking from my money back and telling them to come pick up their junk. I got a lame response from the one guy, he said I needed to contact his partner since I had dealt with him. I told him that I only had one contact number and that was the one I was reaching out on. I told him he had to deal with this.

That was a week ago now. No response.

DO NOT EVER DEAL WITH THE SCUM GUYS FROM PISCATAWAY NJ

[drwillb]

I have received my brand new 1M driveshaft and this week I will order a brand new, shiny subframe. I'll also get new lower camber and trailing arms with nuts and bolts. In the end, the parts I will use from the salvage car will be the diff, axles, and hubs. I do have my doubts about the diff. I wouldn't be suprised if that's blown.

On a brighter note, I took the car to Watkins Glen this weekend and it did well with only the front end M3 parts installed. I was afraid that there would be a big balance problem but it wasn't there. I expected oversteer so I sandbag the first couple of sessions, slowly picking up pace but it wasn't until the 6th session that I started getting a squirmy rear end.

I can't wait to get all the mechanicals done.

[houtan]

Originally Posted by drwillb

I have received my brand new 1M driveshaft and this week I will order a brand new, shiny subframe. I'll also get new lower camber and trailing arms with nuts and bolts. In the end, the parts I will use from the salvage car will be the diff, axles, and hubs. I do have my doubts about the diff. I wouldn't be suprised if that's blown.

On a brighter note, I took the car to Watkins Glen this weekend and it did well with only the front end M3 parts installed. I was afraid that there would be a big balance problem but it wasn't there. I expected oversteer so I sandbag the first couple of sessions, slowly picking up pace but it wasn't until the 6th session that I started getting a squirmy rear end.

I can't wait to get all the mechanicals done.

Sorry to hear about the broken parts. But looks like you are making great progress. Looking forward to more updates.

[Rikx1M]

congrats on an epic build...looking forward to the final verdict

[drwillb]

Thank you, guys. I'm only half way there but very impressed with the results so far. Can't wait to get on the track again with an LSD, matching F/R supension, matching F/R brakes, and nannies coded out.

My instructor was a good friend of mine and he has a fully built, true 1M with MCS suspension and stoptech BBK running R1s. I took a ride with him and, man, that was the best track car experience I have ever had. The thing is on rails and we consistently hit 150-152 on the back straight!!!

I know my car will never be 100% 1M but even 80% of that will blow my mind.