Z3: first track day!

I finally got to drive my 1996 Z3, and at my favorite track no less! Let’s have a look at the spec sheet as it sits.

  • 1.9L engine with 150k miles. It made 138 crank hp when new, so maybe 110 at the wheels right now.
  • Curb weight is listed at 2600, but that’s with a spare tire and without a roll bar or driver. It probably weighs around 2800 lbs. All told, that’s over 25 lbs / hp. Not great on paper.
  • 5-speed manual transmission and probably a limited slip differential (haven’t checked).
  • ABS yes, but there was no stability control back on the 1996 model.
  • The suspension was upgraded to KW Variant 2 by a previous owner. It’s lower and stiffer than stock. Not brutal, but also not very comfortable on bumpy roads. There’s also an upgraded ARB.
  • 225/50/16 Federal Evoluzion ST-1 tires. Tire reviews show that this budget tire is not well loved.

Before heading to the track (Thunderhill West), I tried to estimate the lap time based on previous experiences in a Miata and Yaris. The Miata was often shod in 200TW and did a lot of 1:32s. That was several years ago. It weighed a lot less than the Z3 and probably made similar power. The Yaris runs 1:34s on 200TW. Here’s what I wrote in my notebook.

The Z3 on 300TW tires is not going to be very fast. Maybe 1:35. With a really sticky tire, it might get to 1:32.

The actual lap time was 1:34.001, so a little better than expected. I didn’t write down how I expected it to drive, but if I had, I probably would have written something like “typical BMW goodness”. In fact, it drove even better. I think it’s one of the best cars I’ve driven. It’s certainly not one of the fastest, but that’s not what I look for in a car anyway. You can push it hard, and it responds predictably. It has very little body roll. The rear comes around nicely under braking or throttle. Perfect. Well, except for a few things.

Not every day goes 100% according to plan. My front right brake ran really hot . When I came in after the first session, it was smoking. Almost every driver dropped by to say “when you passed me, I could smell your brakes”. I left the second session a little early and skipped the third entirely. All because my brakes were overheating. I could be sad/angry about the brakes, but I’m so pleased with the car in general that I don’t care. Not sure if the caliper needs to be rebuilt or I need a different pad compound, but I’ll definitely have to address brakes before the next track day.

Another not so great thing was the seat. I had very little support and I had to jam my left foot into the dead pedal to try to compensate. I’m would say that a seat was my next purchase, but I already have a spare, and the Z3 came with race seat mounting hardware. So it’s just a matter of me not being lazy. I may take out both seats as this is really just a track toy.

I also had plans for some lap timer testing and video, but I lost patience partly because I was so cold. Oh well, next time.

8 thoughts on “Z3: first track day!

  1. wow. sounds great. my first track day was stomped because my father-in-law was in a motorcycle accident and my wife went home to support her folks. He’ll be ok, but man, makes you think… i take solace in a) wearing lots of safety gear, b) closed circuit (e.g. no “sand in the road”, unexpected corner, oncoming traffic), and c) i’m currently staying away from tracks w/ big walls / blind corners (ala infineon…). hope your mom is doing better.

    as for the z3, sounds like you had a great time. spring & shock upgrades on good geometry can make a car really fun. seems like you scored! my 2002 was like that. get the brakes fixed and then drive the wheels off that thing! hopefully this year i’ll see you out there. i’m angling toward 4/12 buttonwillow at present. selection criteria is governed by a) weekday, b) little to no walls (buttonwillow / t-hill – both are similar distance from me….. still deciding on whether i’m going back to laguna seca).

    and just so you know, thanks for the posts. i appreciate your stories and point of view.

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    1. My mother is improving every day, but slowly. Recovery takes a long time at 84 years old.

      Motorcycles on the street are scary. Too many oblivious drivers. I would love to ride one on track. That will probably never happen though. Too scared of injuring my back.

      I’m having to replace pads, rotors, and calipers. It was quite the melt down. I’m also going to install a proper seat and maybe a harness bar so I can wear a neck brace.

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      1. hard to believe that they got that hot… must had some dragging. maybe some brake cooling ducts?

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  2. Or larger front brakes? I used to regularly melt my FRS front calipers until I sourced a used Brembo upgrade. Bet there are bigger brakes available for that car – hopefully at a reasonable price.

    I have found that an aggressive driver can heat up OEM brakes despite low power, especially on tracks with longer straights leading to braking zones. I don’t recall how TH West fares on brakes.

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    1. The Z3 uses the same size brakes as lots of heavier and more powerful cars. It’s surprising that they overheated. It’s possible I could use a larger brake, or more cooling, but I’m thinking something was actually wrong with the brakes, like they were dragging. I’ve added brake cooling ducts in the past, and it wasn’t that helpful, but I’m thinking I should do this just in case. I don’t want to have to replace calipers again.

      Thunderhill has some pretty aggressive braking zones. The speeds going in aren’t that high because the track is twisty, but the minimum speed is really low in a couple spots.

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      1. I went to YT University and learned how to rebuild my calipers (it was not all that hard). I bought a spare caliper set to have on hand so I could swap rebuilt ones in quickly (and brake fluid wouldn’t drip). Agree that if you are correct that only one side was hot, then it was a defective brake. Agree that ducts are less effective than big, functioning brakes.

        I also find Centric rotors to be inexpensive enough to swap them out “early.”

        Oh, and I used those adhesive temperature stickers – I believe from Alcon? – on each caliper until I solved my issue. Shows peak temp which is nice because the cooldown lap makes other real-time methods inaccurate.

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  3. On my Miata and Yaris, I used to swap out the rotors on schedule whether they needed it or not (every 3 pad changes). Now I’m using a more expensive rotor on the Yaris and it doesn’t get swapped as often. I need to get these stickers for the Z3 calipers.

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