3002 tii’s Track Day Journal
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3002 tii
Active member
Been hustling last 2 weeks to knock out my mod list. Truthfully, none of these were needed but where’s the fun in keeping things stock!? First up is lighting…
I already upgraded my xenon projectors a while back, but I can’t stand the lack of visibility during fog. And no low beam is going to cut through that unless you source 3K bulbs, which would be a nuisance to everyone on the road. I did consider retrofitting oe fogs but decided it wasn’t worth the trouble (i.e., mess with the LCM, source a new light switch and open up the brake ducts). Then I recalled seeing a race car at my local track with a light bar that looked surprisingly good.
However, I wanted something a little more stealth. So after taking some measurements, I determined there should be enough space to mount it behind the bumper while sitting above the oil cooler.
It’s visible if you’re specifically looking down there. Else, I find that itactually blends in quite well with the lower honeycomb.
Interesting note, this light by Diode Dynamixs is SAE / DOT approved, so it’s legal for street. You can see how the beam pattern widens out without blinding anyone.
I know it’s not everyone’s cup of tea but I dig it, and more importantly it’s functional. Now onto aero changes…
I already upgraded my xenon projectors a while back, but I can’t stand the lack of visibility during fog. And no low beam is going to cut through that unless you source 3K bulbs, which would be a nuisance to everyone on the road. I did consider retrofitting oe fogs but decided it wasn’t worth the trouble (i.e., mess with the LCM, source a new light switch and open up the brake ducts). Then I recalled seeing a race car at my local track with a light bar that looked surprisingly good.
However, I wanted something a little more stealth. So after taking some measurements, I determined there should be enough space to mount it behind the bumper while sitting above the oil cooler.
It’s visible if you’re specifically looking down there. Else, I find that itactually blends in quite well with the lower honeycomb.
Interesting note, this light by Diode Dynamixs is SAE / DOT approved, so it’s legal for street. You can see how the beam pattern widens out without blinding anyone.
I know it’s not everyone’s cup of tea but I dig it, and more importantly it’s functional. Now onto aero changes…
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3002 tii
Active member
Despite my best attempts to convince APR to release a swan neck, they apparently have no interest developing products for cars 20+ years old haha. So the moment I saw a used GTC-250 pop up, I jumped on the deal.
This wing is huge, sitting 6 inches wider and 1 inch higher over my GTC-200. If I’m not careful, the end plates will catch my arm when I walk around the hatch. Despite its larger dimensions though, it does not exceed the width of the car nor sit above the roofline. However, it does hang off the rear deck which is one of my favorite aspects.
To balance out the rear, I shifted my front splitter forward by +1.0 inch. This will undoubtedly scrape, so I added some titanium skid pucks by the leading edge to take the brunt of any impact.
I also incorporated side spats to help deflect air off my tires. Using 1/8” ABS plastic, I cut and molded the spats to follow the curvature of the fender. Side note, the M finally looks like it has wide fenders lol.
The spat is held in by the factory fender rivets along with an L bracket attached to my splitter. At some point I may need to trim the inboard side as I noticed slight rubbing. But I’m also experimenting with the smaller tire sizes. If there’s no noticeable loss in handling with a 245mm front, then trimming may not be required after all.
This wing is huge, sitting 6 inches wider and 1 inch higher over my GTC-200. If I’m not careful, the end plates will catch my arm when I walk around the hatch. Despite its larger dimensions though, it does not exceed the width of the car nor sit above the roofline. However, it does hang off the rear deck which is one of my favorite aspects.
To balance out the rear, I shifted my front splitter forward by +1.0 inch. This will undoubtedly scrape, so I added some titanium skid pucks by the leading edge to take the brunt of any impact.
I also incorporated side spats to help deflect air off my tires. Using 1/8” ABS plastic, I cut and molded the spats to follow the curvature of the fender. Side note, the M finally looks like it has wide fenders lol.
The spat is held in by the factory fender rivets along with an L bracket attached to my splitter. At some point I may need to trim the inboard side as I noticed slight rubbing. But I’m also experimenting with the smaller tire sizes. If there’s no noticeable loss in handling with a 245mm front, then trimming may not be required after all.
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3002 tii
Active member
My calipers have been running hotter ever since I switched to DTC-70s up front. Even with titanium shims, I managed to cook my dust boots last fall. So over the winter, I rebuilt both front calipers with hi-temp boots and seals from OPS. Feedback from M3 owners seem to suggest these are up to the task, but with very little data out there, I figured it wouldn’t hurt to look into some cooling solutions.
On my old 3.0si, I installed brake cooling ducts by the factory fog lights. For the M, I had to get a little more creative since I didn’t want to hack any of the factory plastics. My options were then limited to:
Option 1 - Illustrative Scoop off Control Arm
Option 2 - Illustrative Ducts in the Lower Tray
Even though less air is fed through with Option 2, I preferred its shorter and more direct path to the rotors. So I began tracing the factory tray on a 3mm aluminum composite sheet.
After trimming to shape, I cut out the inlet holes and attached the ducts with some low profile fasteners before sealing the edges with black silicone.
So how will the air be directed to the rotors? Simple… I picked up Westerlund’s brake cooling kit. Install is straightforward. Remove the caliper, use tin snips to remove the dust shield. Use provided hardware to mount the new backing plates.
I have to say these things are absolutely beautiful. The backing plate bolts up to the spindle perfectly and provides the same coverage as the factory dust shields. Best of all, he was even able to customize the inlet to accept a smaller 2.5 inch hose.
The attention to detail is quite obvious. For example, he includes a C-shaped piece to cover the tiniest of exposed area on the hub that forms when you remove the factory pressed dust shield. Other features include a protective cap for the wheel sensor. Basically a Z4 kit offered by a Z4 enthusiast.
On my old 3.0si, I installed brake cooling ducts by the factory fog lights. For the M, I had to get a little more creative since I didn’t want to hack any of the factory plastics. My options were then limited to:
Option 1 - Illustrative Scoop off Control Arm
Option 2 - Illustrative Ducts in the Lower Tray
Even though less air is fed through with Option 2, I preferred its shorter and more direct path to the rotors. So I began tracing the factory tray on a 3mm aluminum composite sheet.
After trimming to shape, I cut out the inlet holes and attached the ducts with some low profile fasteners before sealing the edges with black silicone.
So how will the air be directed to the rotors? Simple… I picked up Westerlund’s brake cooling kit. Install is straightforward. Remove the caliper, use tin snips to remove the dust shield. Use provided hardware to mount the new backing plates.
I have to say these things are absolutely beautiful. The backing plate bolts up to the spindle perfectly and provides the same coverage as the factory dust shields. Best of all, he was even able to customize the inlet to accept a smaller 2.5 inch hose.
The attention to detail is quite obvious. For example, he includes a C-shaped piece to cover the tiniest of exposed area on the hub that forms when you remove the factory pressed dust shield. Other features include a protective cap for the wheel sensor. Basically a Z4 kit offered by a Z4 enthusiast.
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3002 tii
Active member
You are not alone. I had a pair of v1’s as well but can’t fault the guy for continuing R&D to offer a better product!Well this is irritating, that looks amazing and I've gone and bought a 2nd hand previous iteration westersund kit without all the clever bits like the abs shroud
Looks fantastic nice write up!
Oh for sure, the latest ones look fantastic! Have you any before data on brake temps to compare with after data?
3002 tii
Active member
Unfortunately not. I ran out of caliper temperature strips a while back. Though I suppose I can still run a before vs after just by doing a session with and without the hoses connected.
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3002 tii
Active member
After 26 heat cycles my RT660 began cording so I went back to the RE-71RS (not the latest RZ compound ). This time around though I decided to downsize the fronts from 255 to 245. Rubbing wheel liners is semi annoying but I don’t want to have to mold new tire spats after each weekend.
As expected, the 245 on 9.5 et35 clears strut side without any spacers (vs before I had to run 7-10mm).
Outboard side is a different story though, there’s maybe 2 pubic hairs worth clearance with my 996 caliper
but all that matters is the rim spins freely. Track day tomorrow so excited to test all the latest upgrades
As expected, the 245 on 9.5 et35 clears strut side without any spacers (vs before I had to run 7-10mm).
Outboard side is a different story though, there’s maybe 2 pubic hairs worth clearance with my 996 caliper
but all that matters is the rim spins freely. Track day tomorrow so excited to test all the latest upgrades
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3002 tii
Active member
Annual changing of wheel liners. At $20/ea it’s not a huge cost but it would be nice to extend the shelf life to more than 1 year. I am hopeful though with my recent tire change to 245/40, my liners will be spared going forward. Also this time around I double stacked the plastic liners which appears to have increased the stiffness.
3002 tii
Active member
Got the rare opportunity to test out the new M2 Racing. What a fantastic race car. Stating the obvious but nothing comes close to a factory race car. The car didn’t have the fastest straight line speed but it was so well composed. You couldn’t tell it was 4 cylinder turbo. No lag, no heartsick and the 7 speed auto really changed my views on automatics. Would I want one for a weekend car like the Z? Absolutely not but for track duty absolutely. It’s just too good to pass up. The stock brakes (paired with track pads) were by far the most impressive I’d ever driven.
Me sadly exiting the nicest race car I’ve ever driven.
Me sadly exiting the nicest race car I’ve ever driven.
3002 tii
Active member
Been a minute since my last update, but there just hasn’t been much opportunity to get on track. Barely got my car ready in time for my annual trip to Watkins Glen, where I’d see my friends, some of whom brought new toys, including a CTS-V BW, G80 M3 and 991.2 GT3.
Like most race tracks with moderate elevation, Watkins has its own micro climate. And so for the entire weekend it was basically raining every few hours, followed by periods hot sun. If you weren’t dealing with wet surfaces, you were most definitely driving in periods of thick humidity. This made things tricky with the aero — higher AoA helps with grip in the wet but it has a noticeable drag effect on the straights as confirmed by my lap data. Forecast looked great in the morning…
but most of the day looked like this:
My PB was 2:13.2 so I was hoping to crack 2:11s but sadly that did not happen. The brakes performed flawlessly (shoutout again to @Westersund), but with very little seat time, I was just rusty. However, there were some positives from the weekend. With the extra downforce, I was able to take T2 flat, which is the beginning of the hairiest section but where you also pick up the most time. I increased Vmin by nearly +4mph which translated to 1.5-2.0 seconds. Top graph is from when I did 2:13 last year. Bottom was best run from this weekend.
I have a neat video on my IG where my buddy in the red GT3 was behind me when I mustered up the courage to WOT, and it was the first time I was able to maintain some distance. On the not so plus side, one of my wheel sensors went out and I ended up losing ABS and locking up on T1 during the last day lol. At that point, decided it was best to pack up and avoid flat spotting my new front tires.
I do think under ideal track conditions I would’ve cracked sub 2:12. Guess I have something to look forward to next year lol. And for your viewing pleasure…
Like most race tracks with moderate elevation, Watkins has its own micro climate. And so for the entire weekend it was basically raining every few hours, followed by periods hot sun. If you weren’t dealing with wet surfaces, you were most definitely driving in periods of thick humidity. This made things tricky with the aero — higher AoA helps with grip in the wet but it has a noticeable drag effect on the straights as confirmed by my lap data. Forecast looked great in the morning…
but most of the day looked like this:
My PB was 2:13.2 so I was hoping to crack 2:11s but sadly that did not happen. The brakes performed flawlessly (shoutout again to @Westersund), but with very little seat time, I was just rusty. However, there were some positives from the weekend. With the extra downforce, I was able to take T2 flat, which is the beginning of the hairiest section but where you also pick up the most time. I increased Vmin by nearly +4mph which translated to 1.5-2.0 seconds. Top graph is from when I did 2:13 last year. Bottom was best run from this weekend.
I have a neat video on my IG where my buddy in the red GT3 was behind me when I mustered up the courage to WOT, and it was the first time I was able to maintain some distance. On the not so plus side, one of my wheel sensors went out and I ended up losing ABS and locking up on T1 during the last day lol. At that point, decided it was best to pack up and avoid flat spotting my new front tires.
I do think under ideal track conditions I would’ve cracked sub 2:12. Guess I have something to look forward to next year lol. And for your viewing pleasure…
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3002 tii
Active member
In the past year I’ve come around to the idea of trailering the Z4. While car is still comfortable enough to drive to/from the track, the truth is trailering makes things a lot easier. For one, I limit wear n tear on the car. Two, I can run slicks or bring a 2nd set of tires. And three, in the worst case, I won’t have to worry about being stranded in the middle of nowhere. But first thing’s first, I need a tow rig and fortunately my daily is a good candidate.
Call me biased but I think BMW design era peaked with the F series (after E85/86 of course). I can’t think of anything current that I would want to replace it with. My only regret is not getting the diesel but at the time, I did not think I’d need it. However, the 6000# towing capacity remains the same across all engine trims. What’s more important is stopping power, and for that I already upgraded to the larger factory brakes from the 50i model.
As for the hitch itself, I didn’t go with OEM as it uses an annoying system where you have to swap between the class 2 square and class 3 ball mounts. Not to mention, unlike our European counterparts, we don’t get the automatic swivel function making it even less compelling. So after doing some research, I landed on Curt’s class 3 hitch — simple but ridiculously beefy, made in the USA, and doesn’t require any modification to the bumper.
Install was pretty simple, just basic trim removal tools and sockets to undo the rear fender trim, bumper and tail lights.
Though despite my best efforts I did end up snapping the clips on the rear reflectors. I couldn’t find a way to get my hand behind them (from underneath) to pop them out. Luckily new replacements weren’t too expensive.
Even though I went with an aftermarket hitch, I did opt for the factory harness for a PnP install. Well worth its price as I had no interest in splicing wires. Using a generic bracket, I mounted the Pollak connector vertically for a cleaner install.
Overall I’m quite happy with how it turned out. It’s not very visible nor does it stick out very far. All that’s left is to reprogram the VO with Esys and find a proper brake controller.
No clue where I’d even park my non-existent trailer buy at least I now have the option to hook up a U-haul toy hauler. But in the meantime, I’ve already found myself getting some good use out of it.
Call me biased but I think BMW design era peaked with the F series (after E85/86 of course). I can’t think of anything current that I would want to replace it with. My only regret is not getting the diesel but at the time, I did not think I’d need it. However, the 6000# towing capacity remains the same across all engine trims. What’s more important is stopping power, and for that I already upgraded to the larger factory brakes from the 50i model.
As for the hitch itself, I didn’t go with OEM as it uses an annoying system where you have to swap between the class 2 square and class 3 ball mounts. Not to mention, unlike our European counterparts, we don’t get the automatic swivel function making it even less compelling. So after doing some research, I landed on Curt’s class 3 hitch — simple but ridiculously beefy, made in the USA, and doesn’t require any modification to the bumper.
Install was pretty simple, just basic trim removal tools and sockets to undo the rear fender trim, bumper and tail lights.
Though despite my best efforts I did end up snapping the clips on the rear reflectors. I couldn’t find a way to get my hand behind them (from underneath) to pop them out. Luckily new replacements weren’t too expensive.
Even though I went with an aftermarket hitch, I did opt for the factory harness for a PnP install. Well worth its price as I had no interest in splicing wires. Using a generic bracket, I mounted the Pollak connector vertically for a cleaner install.
Overall I’m quite happy with how it turned out. It’s not very visible nor does it stick out very far. All that’s left is to reprogram the VO with Esys and find a proper brake controller.
No clue where I’d even park my non-existent trailer buy at least I now have the option to hook up a U-haul toy hauler. But in the meantime, I’ve already found myself getting some good use out of it.
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