E28: Eggenberger Group A E28 Tribute Build Thread

[SpasticDwarf]

Hello friends!

I've had a whole bunch of folks ask me if I'd put together a build thread for my E28. I figured I'd at least put something together. It'll take me a bit to do the whole thread, and truth be told, with my track record, I'll get partway done and then not come back and finish the thread. But a start is better than nothing I suppose! I also didn't take photos of much of the build process, except for with my phone, so honestly this thread is more of an inside look at the car and the parts on it, as opposed to a start-to-finish build progression.





I've had the old girl out on track at Chuckwalla and Buttonwillow and it's been driving phenomenally, and I'm very excited to continue dialing in and tuning the suspension to maximize the car's potential.

For the sake of thoroughness, here's my "build sheet" of what all is done to the car. It's probably missing a few things, but it's mostly there.

1984 533i, 165,279 miles on chassis.

Custom “Original Teile” Livery, based on GR. A E24

Suspension:
H&R Coilovers, custom made in Germany
H&R Sway bars, one-off, custom made. 30mm front, 25mm rear
Custom adjustable swaybar links
Custom fabricated reinforced swaybar mounts
Ground Control race camber plates
E31 aluminum lower control arms
Powerflex black race bushings for:
Front LCAs
Front UCAs
RTABs
Rear Subframe
Complete suspension overhaul, all OEM:
New front wheel bearings/hubs
New rear wheel bearings
New lock rings and collar nuts
New dog bones
New axles
New rear shock mounts
New front LCAs
New front UCAs
New tie rods and center link
New steering idler arm

Custom 7075 alloy Centerlock hub adapters, Steel drive pins, built to Gr. A E28 spec
Brand new BBS centerlock nuts
Ronal Racing centerlock wheels, 16x8 square
Built with brand new BBS rim halves, sealing rings, and hardware
Pirelli P-Zero Trofeo R 225/45 tires
Tarox 6-pot aluminum big brake calipers, front
E32 750 rear brake calipers
310x26mm slotted front rotors
300x20mm slotted rear rotors
Tarox Corsa track brake pads

Exterior:
European bumpers front and rear
Euro M5 front air dam
Euro headlamps and grilles, with custom crosshairs
M5 rear spoiler

Interior:
NASA legal, 1985 FIA Group A-spec 6-point Roll cage, 1.75” .120 DOM
Pair of Momo Daytona fixed back seats, FIA compliant til 2020
VAC machined seat mounts
Pair of Willains 6-point harnesses, FIA compliant til 2020
Vintage Momo Futura steering wheel
Rennstall white delrin RSKT2 shift knob
Stripped and fully painted interior
Black headliner
Black door cards

Driveline:
S38B35 Engine swap - Pulled from 125k mile car, cluster accurate.
Swap includes complete M5 driveline:
G280 transmission
Rebuilt 4.10 E30 M3 Limited Slip Differential, converted to 3-clutch setup
Custom reinforced rear differential mount
Euro “bundle of snakes” headers
Conforti software
JB Racing 11.5lb flywheel
Clutchmasters 6-puck sprung clutch
Custom short-shift kit
CSF Aluminum radiator
SPAL 16” fan
Maintenance includes:
Complete top end rebuild, fully redone cylinder head
New timing chain
New timing chain guides
New head gasket
New front and rear main seals
New ancillary gaskets
New waterpump
New thermostat
etc.

Fueling:
ATL 120-liter Aluminum fuel cell, 1982 GR. A touring spec
3-liter fuel swirl pot/surge tank
Bosch 044 inline fuel pump
Holley Red lift pump

As a bit of an opener, the car is a bit of a mashup of ideas, most notably, it's inspired by the '82 Group A Eggenberger E28 ETCC race cars.



None of them were blessed with particularly beautiful liveries, so in building a tribute car, I went with something with a bit more flair, and pulled inspiration from the E24 factory works "x-ray" cars.





But, because those are E24s, they're not quite right in terms of simply copying the livery, so I had my good friend and business partner Andrew Ritter redesign the graphics to correctly portray an E28, including the rear seat, doors, etc. We also changed the engine and transmission to reflect M5 components.



M5 components are reflected because that's the final piece to my puzzle. While a built 2.8 M30 would be more correct in the car, it felt wrong to do anything but go for the best the E28 had to offer, despite the fact that the S38 was never homologated for FIA racing. I used an M5 donor car to contribute all of the parts, including tidbits like M5 door sills, to keep things authentic.

The build itself is something I've been planing for quite a few years, but last year I was given the opportunity to realize the vision and bring it to fruition. While the Group A E28s serve as the basis for the build, my initial inspiration was a french Superproduction E28. I had originally planned to copy this car, to a T, but with the influx of Marlboro-themed cars out there, I didn't want the effort to go to waste in the mix of something trendy, so I shifted my gears and worked towards the car I have today. (Humorously, halfway through my build, this exact car surfaced and went up for sale. When I had found photos a year or two prior, I had assumed it was long gone.)



Anyway, on July 1 of last year (2016), I picked up a reasonably nice example of an early body E28, which I wanted due to the fact that the race cars were also early-body. It was white over cardinal red in good overall shape.

[SpasticDwarf]

As said, I don't really have a great chronological collection of photos, so I'm more aiming to showcase the components of the car, or at least parts of it.

The suspension and underside of the car were the most important to me. I worked closely with H&R to build a special setup for it, and BimmerWorld helped to supply to parts necessary to overhaul literally everything.



Most here in the US are unaware that H&R builds complete coilover kits for the E28. While they're expensive, they're also a bolt-on affair engineered specifically for our chassis. For anyone interested in a set, feel free to reach out to me and I can help to get you set up.

We also built a one-off set of sway bars as an exercise in curiosity and experimenting. Aftermarket swaybar options are limited for E28s - M5s are equipped with 25/18mm bars front and rear, and can do so because of special sway bar mounts. Non-M cars have more fragile mounts, and require reinforcement to the chassis in order to upgrade to larger bars. There are a few companies that make larger bars for our cars, with the largest being an M5-spec 25mm front and a slightly upgraded 19mm rear bar, as far as my research has shown. We opted to size up substantially, with 30mm front bars and 25mm rears. At the moment, there's no plan to put these into production, but if others are interested, a group-buy might be something I can help put together.



To mount the sway bars, reinforcement was needed. I opted for Aaron's (limitedslip engineering) front mounts, since he clearly did a nice job with his kit. I ordered a second pair of D-mounts and bushings from him for use in the rear of my car. For the front, I bored out his largest D-bushings to accomodate my bars.



For the rear, he offered an upgrade for the swaybar mounts on late-model E28s, but for the early car, the mounts are different, and much more fragile. Tearing them from the body is a common occurrence with upgraded sway bars, so I designed my own reinforcement setup, and welded it into the car. I fabricated a differential mount reinforcement setup while I was under the car as well, and can find a photo if people are interested.



For the build, I stripped every component from under the car, except for the factory fuel and brake hardlines. I modified the rear subframe with an Ireland Engineering posi-lock style toe/camber adjustment kit, and then had both subframes, and the trailing arms powdercoated in a factory satin black.



With everything apart, I wanted to replace every component underneath the car, so I had BimmerWorld source everything needed. All four wheel bearing assemblies, the hubs, the axles, all of the bushings, control arms, steering components, dog bones, shock mounts, and even brake shields, nuts and bolts were all replaced; some pictured, some not. Every part used was OEM, including the Lemfoerder arms, which I pressed the bushings out of to replace with Powerflex components. I used black Powerflex bushings on every component they offer, except for the sway bars, and the LCAs.







Seen before the bushing swap:



The rear end, mocked up:



Today, the only thing I have planned for the underside of the car is a cryoblast session to restore it to its former shine. I considered stripping and repainting the whole car, but it didn't make sense on a car I actually want to drive and race. A perfect show-car undercarriage would be pretty to look at, but flinging rocks and debris at it with R Comp tires seems like wasted effort.

My original plan was to use the M5's large-case 3.91 diff, but it wasn't until trying to physically install it into the car that I realized that it would take more than just a rear mount modification to pull off. The floor pan is different in early versus late E28s, with the early model floor pan providing inadequate clearance for the larger differential case. I opted for an E30 M3 4.10 LSD, as it was a direct bolt-in solution. I'm currently in the middle of rebuilding it with a Thayer 3-clutch kit, new bearings, seals, and hardware. The 4.10 was a great choice in this car when paired with the G280's long gears. I really enjoy the way it drives.



I wish I had more photos of the suspension to show off the thoroughness of the build, but that'll have to do. No expense was spared in the running gear of this build. I wanted it to be thorough, and true to form in wanting an E28 that drives better than new. The only factors that I am unhappy with would be the lack of true Group A trailing arms. The front components will be swapped out for Group A bits in the coming months, as those are much more simple.

[SpasticDwarf]

The wheels are probably my favorite part of the build, and might be the most important part. In wanting to build a spiritual “sister car” to the E24s, it was important to use the correct wheel. I found these Ronal splits, off of a Group A car, a few years back, I believe in 2012, and have been sitting on them ever since. They’re a spot-on match for the E24s, and as run on some of the E28s as well.





Using a few reference materials, primarily homologation papers for one of the Gr. A E28s, and an old rear hub I happened to have here at the shop, I joined forces with one of my closest friends, Nic Foster, to build a set of centerlock hubs for the E28. Pictured below is the original hub I had, which I sent to Nic up in Seattle, so that we could replicate it.



The factory E28 race cars are setup slightly different to our road cars, as their strut-to-spindle attachment is a a bit different from the road cars as it’s a BMW Motorsport coilover. However, it does utilize the factory geometry and the stock steering arm, so it’s practical difference is, well, none. You will note, however, that the hub assembly is almost identical. We used my spare factory centerlock hub for measurements and dimensions for both the hub and the drive pins. Pictured below are two photos from the E28 FIA homologation papers - the motorsport strut assembly, and the centerlock unit.





For our hub, we did add some lightening holes (as also used on the original hub I own, but not as seen on the Gr. A E28s in the pic above), however, they do use the drive pins to affix to the car - they’re not a dual-bolt style “adapter”. It’s as close to the factory centerlock hubs as we could venture.



We produced the parts with a 7000-series alloy and FEA testing shows the load capabilites well past 4x the German TUV minimum safety rating, so this is a true race-capable part. A crows foot and torque wrench is used to install them to the car via the drive pins.



Ronals were built, back in the day, to BBS dimensions and to utilize BBS hardware. BBS supplied me with NOS centerlock nuts, as well as the original ’83 CAD drawings so we could perfect our hub and mate them perfectly.





For the wheel build, I simply rebuilt them to factory spec with new BBS inners, outers, bolts, nuts, and sealing rings. I left the wheel centers as-is, opting to not refinish them in favor of retaining the patina and as-raced marring and imperfections.





All of the components fit together perfectly, and I was eager to see them on a car. At the time, the white car had no subframes, so mockup there wasn't an option. Here’s a few photos of initial test-fit on my M5 of all of the components. Sorry for the rusty surfaces - it’s been sitting since ’94, and is on my list of builds to do. Seeing them on an E28 had me excited and eager to finish up the suspension build on the race car.



And the original, for comparison:



Wheels on!



Mounting them on the race car was pretty straight forward, as per above. Torquing the wheels down required me having to have a custom 90mm socket made. While you can buy one ($1200 from SnapOn for the one socket, $400 for the cheapest out there), it was cheaper to have one made. The nuts are torqued to 400lb-ft.

[stonea]

Damn, this thing is so cool!

[Shock(/\)ave]

This is probably my favourite of any of your builds (and I've seen your work since your first threads on bimmerforums.com). The stance is period correct and fully functional, the wheels are perfect and just the right size for the chassis, and the livery is fantastic. Your tastes have certainly matured. ;D

More pictures and background on the E28 M5 would be great (or a link if you've posted about it somewhere else).

How many cars are in your collection now? I haven't kept track, but would guess you've sold your E36 and E9...

[Eric]

Great stuff Mike! Cool to see this project coming together after years of thought. What is the difference between early and late E28's? When did the switch happen?

How do you like it on track? I found my M5 to be fun, but a bit slow by modern standards. Still a hoot to make the old girl move about! I like the 16" wheel/tire choice, the E28 chassis likes a 16" tire so much more than bigger wheels



Some things that I've upgraded on the M5 and really liked:
-Spherical ball joints in the upper control arms. I used BF.C's Wokke's complete kit, but I'd probably do mooshead's if I needed to do them again. My bushings failed pretty quickly, and the spherical's have lasted much much longer and feel better as far as brake dive and turn in response

-steering box mount upgrade. I made my own, but fixing the steering box mount with that $20 kit the dude on mye28 sells is an easy upgrade to save yourself from hunting for that one clunk you could never pin down
Untitled by ericandshovin, on Flickr

-Intake mods. I've recently rebuilt my B35 as well and it runs SO MUCH BETTER with a few little intake mods. Previously, with a Miller MAF/WAR chip and Stebro back box, the car made 234rwhp at 6,000ft elevation. Since the top end rebuild I've increased the airbox intake size from 3" to 4" (It's 4" from airbox to plenum now) B36 intake cam, slotted cam gears custom timed by the gentleman who assembles Paul Burke motors, and the M88 headers. I haven't dyno'd it yet (I want to) but It runs so much better now, it has to be making a good bit more power. If I were to do anything different would be to use the PNP megasquirt kit to have more control of the tuning. Before the Miller MAf I had the Jim C chip and I'd butt dyno guess that my car now has 60hp more than it did with the Jim C chip, it's vastly different!
Untitled by ericandshovin, on Flickr

[Eric]

Also, I just noticed in the last pic that you have the car side pipped! How does it sound with the M88 headers and side pipes??????

[paynemw]

Ahhh soo awesome! This makes me miss my e28 and wish I found another 535is worth a shit.

[Rontgen]

Wow! Just...wow! I'm speechless.

Well done and thanks for sharing!

[Jjaniiii]

Damn this looks good!!

[SpasticDwarf]

This is probably my favourite of any of your builds (and I've seen your work since your first threads on bimmerforums.com). The stance is period correct and fully functional, the wheels are perfect and just the right size for the chassis, and the livery is fantastic. Your tastes have certainly matured. ;D

More pictures and background on the E28 M5 would be great (or a link if you've posted about it somewhere else).

How many cars are in your collection now? I haven't kept track, but would guess you've sold your E36 and E9...

Thank you, I appreciate that.
I don't have any photos of the M5 to share - it's a long-term project and currently looks the same as it did when I pulled it from where it had been parked decades ago. It's not a pretty car.

I sold the E9, but I still have the E36. I currently own it, the M5, the E28 this thread is about, "Rusty," and two Toyota Land Cruisers.

Great stuff Mike! Cool to see this project coming together after years of thought. What is the difference between early and late E28's? When did the switch happen?

How do you like it on track? I found my M5 to be fun, but a bit slow by modern standards. Still a hoot to make the old girl move about! I like the 16" wheel/tire choice, the E28 chassis likes a 16" tire so much more than bigger wheels

Some things that I've upgraded on the M5 and really liked:
-Spherical ball joints in the upper control arms. I used BF.C's Wokke's complete kit, but I'd probably do mooshead's if I needed to do them again. My bushings failed pretty quickly, and the spherical's have lasted much much longer and feel better as far as brake dive and turn in response

-steering box mount upgrade. I made my own, but fixing the steering box mount with that $20 kit the dude on mye28 sells is an easy upgrade to save yourself from hunting for that one clunk you could never pin down

-Intake mods. I've recently rebuilt my B35 as well and it runs SO MUCH BETTER with a few little intake mods. Previously, with a Miller MAF/WAR chip and Stebro back box, the car made 234rwhp at 6,000ft elevation. Since the top end rebuild I've increased the airbox intake size from 3" to 4" (It's 4" from airbox to plenum now) B36 intake cam, slotted cam gears custom timed by the gentleman who assembles Paul Burke motors, and the M88 headers. I haven't dyno'd it yet (I want to) but It runs so much better now, it has to be making a good bit more power. If I were to do anything different would be to use the PNP megasquirt kit to have more control of the tuning. Before the Miller MAf I had the Jim C chip and I'd butt dyno guess that my car now has 60hp more than it did with the Jim C chip, it's vastly different!

Also, I just noticed in the last pic that you have the car side pipped! How does it sound with the M88 headers and side pipes??????

Thank you. The differences, as a whole, between early and late E28s are pretty slim. They have slightly different floor pans in the rear, use different differentials (although they're largely interchangeable), ABS vs no ABS on the old cars, etc. The bodies are the same, and there's no way to tell a difference between them unless you poke around underneath one, or if you spot a 533i badge. The switched happened from 84-85.

I love the car on track, and it has been a blast. So far, I'm happy with the 17" wheel/tire choice, mostly due to sizing options. My original plan was to run 16s, but I found things to be a bit too restrictive.

I talked to Paul at Moosehead about getting a set of spherical bearings for the UCAs in the front, and it's on the eventual list of things to do. I think you're absolutely right there.

The steering box mount reinforcement is something I wish I had done before getting the subframe powdercoated. I figure once I have a problem with it, I'll build another front subframe and swap it in.

Your performance mods sound fantastic. I've considered similar stuff, but am conflicted, as although the S38 was never homologated, I'd like to leave it factory, as it would have been raced, if it were. (Although cams and a .6mm over bore are allowed by the FIA at the time.)

The car sounds great with the exhaust setup. I have a short video clip I'll have to figure out how to share.

[SpasticDwarf]

Thank you, everyone else, for the kind words.

[CorvallisBMW]

Wow, what a build! Congrats on one hell of a car :up:

[rturbo 930]

I didn't realize how much work, and how many specialized parts went into this build. I thought it was just an E28 with a wrap, and an S38. Pretty cool. I agree with ShockWave that your taste seems to be maturing, which is good to see. Also nice to see at least one of your E28s on a track ;)

I gotta hand it to you though, it's impressive how you've built a brand and business for yourself. I remember you posting something on TDF (remember that site?) maybe 10 years ago about how you were going to do an S54 swap in your E36, and thinking no way this kid is gonna do such an involved swap. Well done.

BTW, what other Land Cruiser do you have? I thought you sold the FJ40 recently.

[JuusoIemel]

Good lord that thing is sexy!