German Car Day 2016

Great day at Larz Anderson Park in Brookline for the German-themed lawn event! It had to have been the most attended German Car Day ever. Sadly, there were only two E21s in attendance (both 323s) and it didn’t seem like we got much attention. There were fewer E30s and E36s too than I expected. Porsche and BMW were the most represented and I was disappointed with the lack of Mercedes. There were too many people to bother trying to take quality pictures.

323i brothers


end of the day


German Car Day 2016

An M6 for the Night

I needed to arrive in style for the opening of the Porsche-BMW exhibit at the Larz Anderson Auto Museum. Luckily, we just got this new BMW F13 M6 as a demo car so I borrowed it for the night.

It’s a 2016 in Sakhir Orange with matching extended Sakhir leather. It also has the carbon brakes option. Our race team campaigns two M6 GT3 cars in the IMSA GTD class. There is a lot of similarities between the race and production car, especially in the engines.

I’ve driven a few of these cars before but they’re almost always modified. This was my first extended drive in a stock car. Every time, I am overwhelmed by the gadgetry inside. This was a rainy evening so I needed to find a wiper setting, turn on the front and rear defrosters, plug my phone in, adjust the mirrors, find a good seating position, and set a decent radio station. I was under way in less than four minutes.

The seating position puts you very low, which is exaggerated by the high belt line. I could only guess at the approximate location of the corners. The overhangs are generous but most of the weight is within the wheelbase. Check out the front seat location in the photo above. Somehow, the M6 manages to feel almost nimble. Our race drivers say the same thing – great balance and the car is very easy to drive. This was a blessing and a curse as I wound my way down Route 1, Storrow Drive, and the Jamaicaway before arriving at Larz Anderson. Boylston Street was especially nerve wracking with that giant beak leading the way. I once drove a McLaren F1 down the same route and this was worse. The 6 series can’t really be any smaller though, or it would be a 4 series.

Power was as expected from an M-tuned 4.4L twin turbo V8, once you got past the lag in the first quarter-inch of pedal travel. I never went full throttle because of all of the thrust available. I’ll be driving an M5 soon with proper ECU tuning and it will be interesting to see how much better the throttle mapping is.

Another complaint is the sound, or lack thereof. Twin turbo cars are not known for volume anyway. But even with the engine sounds funneled through the stereo speakers it’s still inadequate. If I owned this car I would have to install the Turner muffler delete pipes, or something similar.

This car is just too much – bodywork, gadgets, power, luxury. It would make a great cruise missile with first class accommodations. Or if there were autonomous features that took all the stress away from the parking and close quarters maneuvering. Then I could devote all of my attention to learning the dash.

I feel as though this is the zenith of BMW performance, technology, and driving dynamics. I can’t imagine needing anything more than what this car provides, except all of this in a smaller and lighter package (like what you get in a 435i M Sport). Maybe I just appreciate what I have and don’t need additional complications – this is an E21 blog, after all – but I think BMWs stopped being the Ultimate Driving Machine after the E46 M3, with a few low volume exceptions.

An M6 for the Night

Reviving A Dead Optima Red Top Battery

I stupidly left the key on in my 323 for over a month. I don’t know how quickly the battery drained but it wasn’t completely done – the trunk light was still dimly lit but nothing else. 

This was a brand-new Optima Red Top and I wasn’t about to spend $150+ on a replacement. Unfortunately, neither of my chargers was having any success. Fortunately, the Optima website is very consumer-friendly and not only did it explain why my chargers didn’t work, it had fantastic instructions for reviving a spent battery.

My off-the-shelf, generic chargers have their own logic that will abandon the charging process if it detects battery voltage to be below a certain threshold. My dead Red Top was down to 1.5v according to my multimeter. The charger will give it a hearty try but call it a lost cause if the voltage can’t be maintained above X.Xv. 

The Optima website gave three options:

  1. buy the correct charger for an AGM battery that will not give up
  2. use the Optima as a slave to a good battery as the master (and keep the master charged)
  3. bring it to a professional shop who will do either 1 or 2

I opted for #2 because I can’t turn down an opportunity to learn a new skill. I bought a set of jumper cables (always good to have those anyway) and connected my Honda battery to the Optima. Right away I had 10.2v at the Optima. 

Then I connected my strongest charger to the Honda battery. I checked voltage every 15 minutes and in under an hour I had 13.4v on the Optima!

I then disconnected the jumper cables and put the trickle charger back on the Red Top and let it do its thing. After two hours it was still going! I had infused enough electrons into the Red Top that the charger’s fuzzy logic accepted. I let the charger work overnight and it continued to put out over 13.5v the next morning. I drove the 323 to work that day with no issues and the voltage gauge reading over 13v the whole time (between 12-14 and closer to 14).

I guess you can say “I’m charged up!”

Reviving A Dead Optima Red Top Battery

E21 Winter 2016 List

List of things to do this Winter:

Finish garage wall! Can’t do much when I have one of the walls under construction. And I need to plan the layout to allow me to work in the Winter. The original M20B23 engine is on an engine stand and more in the way than I expected. COMPLETE!

Complete the wiring for the M20 swap. It’s all there and connected and everything works. I just have to run the sheath over it and plug the metal connectors into the right places on the fuse box plug and C101 plug. I’m only using 7 pins but there are 20+ connections so I have to get it right the first time. I have a few spare connectors but it still makes me nervous. Then I have to mount the C101 connector on the firewall. COMPLETE!

I also need to connect the VDO oil pressure and oil temp sender. Edit: this is not going to be as simple as screwing it on and plugging in some wires. The owner’s original wiring is incomplete. I’ll have to re-do that too, all the way back to the gauges.

Then install the cowl cover and the engine swap should be 99.9% complete. COMPLETE!

I should set the idle speed to a more normal 750-800 RPM. It’s still up over 1,000 to keep it from stalling, but the O2 sensor seemed to take care of it. I might have to wait for warmer weather to do this though.

The temp gauge only gets to 1/4 on the gauge. I’m running the standard E30 80* thermostat and E21 fan. With a cold temp the DME richens the fuel mixture. I can adjust the fuel map but probably better to have the temp in the right place before I start tuning. First I’ll try removing the fan (done.). If that doesn’t work I’ll install a 88* thermostat. 

Other work on the engine should be: check the bottom end and make sure the rod bolts are tight and there are no spun bearings, and check for any leaks. COMPLETE! Bearings look great. A few small leaks from loose bolts and hose clamps. 

While I am around the subframe I need to replace the tie rod boots because they are ripped (COMPLETE! What a job to get the inner tie rod off!). And finish rust-proofing and painting the frame rails.

On the inside, I have a full Euro non-A/C center console to install. That will mean removing the radio (maybe a new one?) and reinstalling it in the normal horizontal position (COMPLETE! Center console is installed and looks great!). I need to fix or replace the radio antenna. I need to fix a few pieces of the center console before installing it. And I don’t have any hardware for it (COMPLETE! Hardware was sourced from Lowe’s and it looks great). At the same time I need to fix the heater controls because the temp and the vent knobs don’t move. I’m hoping I don’t break anything. And I want to check the hazard light switch because they are a known to be problematic (I bought a backup to have).   

how I want my interior to look

I don’t have the ECU mounted. It’s just dangling on the floor (COMPLETE! Mounted to the firewall. The glovebox closes too. Need to tidy up some other interior pieces and I’ll be ready). I want to try the Ostrich emulator so I can make tuning changes on the fly. And I have to recalibrate the wideband O2 sensor in the Spring (COMPLETE).

Lastly, I need to modify my battery hold-down tray so the Optima battery fits in it. It was supposed to fit but Optima must have changed the case and the battery tray manufacturer didn’t come out with a new one. 


I also installed new hood and trunk BMW emblems (roundels) and new wheel emblems.

Wow that seems like a lot! I’ll probably go down this list in order rather than pick and choose. But it all needs to be done before I can really start driving the car in 2016.

E21 Winter 2016 List

The Infamous E21 Shimmy

The E21 suffers from a front-end shimmy between 50-60mph. This plagued the E21’s reputation and led BMW to introduce a brand new front suspension design for the E30.

I’ll tell you about my car first and then get into the usual causes. My car had a shimmy from around 40mph and then it went away. It didn’t have the usual 55mph shimmy. I wasn’t too concerned about it since all of my focus has been on the engine swap. 

Then on one of my test drives I realized the shimmy was completely gone! No shimmy at 40, 50, or 55. I completely expected there to be something because there were loose control arm bolts, ripped tie rod boots, and I don’t think there are any of the usual shims or stiffer bushing fixes commonly used (see below). The previous owner said he liked the handling “lively”. My guess is that the tires were slightly squared from sitting for a few months. 

The shimmy has quite a few potential causes: 

  • the shimmy is inherent to the design because there is no locating link [solution: none other than full tubular A-arms]
  • worn ‘outer’ control arm bushings where the sway bar connects to the control arm [solution: replace with Genuine BMW rubber or urethane]
  • loose or worn wheel bearings [the wheel bearings should be re-tightened every 20k miles]
  • bent wheel(s) [straighten or replace them]
  • flat-spotted tires [drive on them for a while and they should re-shape themselves]
  • worn sway bar bushings on the frame rails [replace bushings with rubber or urethane]
  • wheels torqued to the wrong spec [loosen and then re-torque]
  • the wrong wheels (the wrong center bore or bolt pattern) [confirm wheel specs. If these are the wrong wheels, replace them right away]
  • bad strut or strut mount [replace strut inserts and mounts]
  • worn steering rack bushings [replace with urethane]
The Infamous E21 Shimmy

E21 323i Exhaust Layout

One of the first things people notice is that the 323i has a dual exhaust. It’s the only modern BMW with one until the 1998 M Roadster arrived. The single tips on both sides give the car some added muscularity and I love them.

The rest of my car’s exhaust is also interesting. It is a true dual exhaust; each exhaust outlet is traced back to one of the manifolds on the engine. Even though this is an inline 6 engine, we still refer to groups of cylinders as “banks”, just like in a V layout. Bank 1 is cylinders 1-3. Bank 2 is cylinders 4-6.

There is no X or H pipe in the exhaust stream. This would probably improve performance but BMW didn’t see the need. There is a center resonator and a muffler on each side. There is no catalytic converter which I have seen on other grey market cars. 

The sound is fantastic. There’s a bit of rasp throughout the RPM range. Because I’m still breaking in the new engine I haven’t revved it past 5,000 RPM but I bet the sound is glorious. Can’t wait to get the car on some backroads in warmer weather and open the sunroof and windows. Video to be added when that happens.

Update: Supersprint just told me that they are re-introducing their headers and all-stainless sport exhaust. That will bring some more power and improve the sound even more. They’re going with 2 round tips on each side (4 total) though. I’ll have to see how that turns out.

Update 2: the Supersprint system has been ordered! I went for the whole system – headers, center section, and mufflers. Supersprint will have two muffler types available: Performance with 4 60mm tips and Race with 2 60mm tips. I opted for the Race mufflers because I want an aggressive and “ripping” sound. If my past experience with Supersprint holds up I think I’ll be pleased. 

Some of my favorite 323i M20 exhaust sounds –

E21 323i Exhaust Layout

E21 Wheel Info

The original E21 320i and 323i wheels were 13×5.5″ with an 18mm offset (ET). There was also a 13×6.0″ ET13 Motorsport wheel available. These sizes  are slightly larger than what was used on the 2002 models. It’s interesting that BMW did not give the 323i a wider wheel.

If you want to maintain the the OEM appearance from the factory wheels you can use wheel spacers. A 15mm or 20mm spacer would work nicely.

Tuners at the time jumped all the way to 15″ wheels for their upgrades. Here are three examples –
Alpina Kopi – 15×6.5 ET20
Melber – 15×7.0 ET12
Ronal LS – 15×7.5 ET25

Of those, the Melber wheels are the most aggressive, putting the wheel 25mm further out towards the fender. We can use this as our benchmark as a “maximum aggressive” fitment. Meaning, if they were any further out they would probably be rubbing on the fender. But they look impressive!


The Ronal are the second most-aggressive, adding 18mm to the track on each wheel. The Ronal is an E30 fitment so there are few resources to go by.

The Alpina Kopi (replica) wheels are the more conservative but still give 11mm of extra poke from the stock fitment.

E30 325i wheels are not a direct fit. They are a good size but a higher offset –
BBS Style 5, “Basketweave” – 14×6.5 ET30
BBS Style 5, “Basketweave” – 15×7.0 ET24

The higher offset means the wheel sits closer to the inside of the car (towards the strut). To use the E30 wheels you will need to use wheel spacers, probably a 15mm for the 14″ and a 5-8mm for the 15″ wheels.

Here are 14″ E30 wheels on 12mm spacers –

Of course, the one variable I left out of this is the tire size. Running tires with a taller sidewall would lead to rubbing. I left tires out on purpose because of all of the variables in sizes.

Have something to contribute? Let me know in the comments section below.

E21 Wheel Info