Derek's E90 slicktop OEM+ Project

[cyberkaa]

The caps are a nice touch

[reidetailing]

Originally Posted by cyberkaa

The caps are a nice touch

In agreement with the center caps being a nice touch...I do like the look w/o center caps, but this cleans it up!

Actually got mine too from System Motorsports (ordered August 2020) for my Mag Blue OG TEs!

[derbo]

Originally Posted by cyberkaa

The caps are a nice touch

Originally Posted by reidetailing

In agreement with the center caps being a nice touch...I do like the look w/o center caps, but this cleans it up!

Actually got mine too from System Motorsports (ordered August 2020) for my Mag Blue OG TEs!

I think I made the decision to buy caps because these became my street setup. It just looks more complete for a street car. Obviously on the track we remove them so my Titan 7 rims do not have caps. 😬

[derbo]

Labor day drive

[derbo]

Time for a Brake Part Deux

After the last track day in July, my Stoptech rotor rings started to look tired. This seemed particularly oddly fast but I do think it was partly my fault. If my theory is correct, I kept the dust shields in place (per the instructions ST provided) so it was no surprise that 100F HPDE days outputted high heat on the inner face of the rotors and the stress cracks reached the edge. This was all after 5 events.

As you can see, the cracks hit the edge of the rotor, toasting them.The most logical thing to do would be to order new rotor rings, and new seals to rebuild the ST60.


Of course, that didn't happen. Enter the company Paragon Brakes. I first heard of them from the Civic Type R folks and heard good things about them.There is also a racing team using them at 25 hours of Thunderhill so there must be some sort of reputation. I figured what's the harm to chat about brakes. So I emailed them to talk about kits. After a few email exchanges, I ended up getting the following setup:

• AP Racing 9660 Calipers
• AP Racing anti-rattle clips
• Paragon Caliper brackets
• Paragon 372x34mm 72-vane Rotors
• Goodridge brake lines

With Paragon's in house facilities, they were able to create custom rotor specs. I noticed European AP racing 9660 front kits favor 378x36mm rotor ring setup while Essex sells a 372x34mm. After some flailing, I decided to increase my 18" rim barrel clearance and order the 374x34mm slotted setup. The rotor bells from Paragon also were compatible with the AP Racing J-Hook rotor rings 372x34mm if I were to swap out.





For brake pads, I decided to follow the combo of Ferodo DS2500 for street and DS3.12 for track use. I haven't been able to get the car out for bedding yet, but so far the car feels great on the new brakes. I also replaced the rear OE rotors and OE handbrake assembly..might as well.




I'll have better feedback after my next track day at 11/28 Laguna Seca on how these brakes feel. It will be my first time back since my spin last year in October and should be fun!


What's upcoming

After this track day, I have ideas on what's next. I bought BimmerWorld solid subframe bushings last Black Friday but never ended up figuring out what I wanted to do. My original idea was to replace every rubber bushing with spherical bearings but I dropped that idea a month or two ago. The idea of corrected roll centers is rather pleasing but I don't know if it is necessary as I am not that low. I also have SPL rear toe links to install whenever I get another alignment.

The flat ride concept has consumed me lately into the deep end, so I may experiment some spring changes. 400/900 + 29mm Eibach sway is looking like something I want to try.


Final fun fact, GTS "race" mode is 12mm below ZCP height, so I ended up accidentally with that setup by dropping my car around 10-13mm from ZCP height!


Congratulations if you read all this. Till next time!

[cyberkaa]

Those brakes look great and should hopefully solve some of the issues with the ST setup.

Looking forward to hearing your feedback on how well flat ride works at the next track day.

And I can't wait for mine to arrive.

[LeontiyZHP]

Looks really clean!

[g.m00]

I like what you did with your wheels.

They provide an intense smoky look that contrasts and complements the white of your car.

Sharp

[wyatth]

Delicious!

[derbo]

Return to the Seca

2021-11-28 marks the return to Laguna Seca in my car. A year and a month after my T1 spin, I am back to enjoy the track again.

Since the last outing at Laguna Seca, a few items have been changed:

• 600/900 springs
• RIP GTS lip
• Hankook RS4s on 18x10.5 instead of PS4S on BBS GT4s
• AP Racing 9660 replacing the Stoptech ST60s
• Ferodo 3.12 vs Hawk DTC60
• DSC off

The goal for this past weekend was to get familiar with the new brake setup as well as gain confidence back on the track.

I really love how the E9x can pack so much into the car.






I'm a bit sad we didn't take any paddock pics but slcook54 SAMM3Y were in on the fun for the weekend. SAMM3Y ran into some suspension trouble on the 1st session and quickly ended his day. slcook54 did great and was hitting some great PB times!

As for me, it took most of the day to rekindle my confidence over T1 with WOT. The uneasiness of it the rear will come loose at the top of T1 keep going through my mind every lap. By the end of the day, I was doing WOT over and just committed! Either way, the pace of the day was slower by 2-3 seconds of my best laps on the PS4S tires back in October 2020. I think the RS4s were losing grip as well as my own mental game prevented that time to be matched or improved. The hankook RS4s are around 5 1/2 events old and probably have at least 20-25 heat cycles on them. That said, the car did great and my initial impressions of the AP racing brakes were what an incredible caliper. The brake pedal is firmer than the ST60s and there is a level of confidence in the pedal I did not have before with the ST60. The Ferodo 3.12 pads did very well and I have 0 complaints from the pad or the brake system now.






# Media Frustrations
I had a lot of frustration with my GoPro hero9. For whatever reason, it would start recording on the pit lane and as soon as I exited to T3, it would shut off. I could not figure out why it is doing it and still do not know what's wrong. I'll try turning off the GPS and doing some tests in the car in the future to see if I can reproduce the issue.

My wife wasn't on track with me this weekend so she let me borrow the Garmin Catalyst so i got a few laps in with that.

This isn't the best lap I've ever done but it was the best of the day. I lifted at T1, etc etc, enjoy the slow video.

Also my car is super quiet, passes 90dB full WOT.


## Post HPDE
I haven't done full analysis of my AIM Solo 2 data yet but I suspect Sunday was mainly a mental game with traction and I played the safer side of things keeping under the limit a little too much. The confidence is back to maybe 95% and next time around will hopefully be more fun!




Black Friday, I did order a Dinan DIY tune kit and pulleys so those will be coming up. I also ordered Bimmergeeks Pro Tool so I could do more coding for others as a service. The car is in a good place right now and time to enjoy more track days with it.

Thanks for getting this far into the journal. Cheers!

[derbo]

[Exclusivs]

Great updates derbo 👍

Question: where did you mount the garmin camera? High on windshield? Center? I don't see the rear view plastic cover in your video that's why. And it's great

[derbo]

Originally Posted by Exclusivs

Great updates derbo ��

Question: where did you mount the garmin camera? High on windshield? Center? I don't see the rear view plastic cover in your video that's why. And it's great

Right under the mirror, dead center. I did buy a Garmin suction cup instead of the supplied 3M tape mount.

https://www.amazon.com/gp/product/B0...?ie=UTF8&psc=1

I'm still frustrated at the whole gopro experience and not sure why it turned off on its own. Some say its overheating..but it survived 100F weather at Thunderhill...others say its the SD card..hmm idk.

[Exclusivs]

^using same one. Did you remove plastic rear view trim?

Ironically enough: suffered go pro 9 failures last outing. It just turned off and wouldn't turn back on. Tried new battery, nothing.

Got home - and got it to "wake up" by plugging into pc. Very frustrating. Working fine now, but skeptical. Maybe last update? Dunno.

[derbo]

Originally Posted by Exclusivs

^using same one. Did you remove plastic rear view trim?

Ironically enough: suffered go pro 9 failures last outing. It just turned off and wouldn't turn back on. Tried new battery, nothing.

Got home - and got it to "wake up" by plugging into pc. Very frustrating. Working fine now, but skeptical. Maybe last update? Dunno.

I did not remove anything. I put it directly below the rear view mirror trim.

I'm not sure. It was working 7/31 and the last update was sometime in June.

[Exclusivs]

I see now and looking good! Unsure if having it not at highest point in windshield has any effect...vids sure look better though!

[DRLane]

Originally Posted by Exclusivs

^using same one. Did you remove plastic rear view trim?

Ironically enough: suffered go pro 9 failures last outing. It just turned off and wouldn't turn back on. Tried new battery, nothing.

Got home - and got it to "wake up" by plugging into pc. Very frustrating. Working fine now, but skeptical. Maybe last update? Dunno.

This is basically every other track day. I hate GP.

[derbo]

Originally Posted by DRLane

This is basically every other track day. I hate GP.

Yea, thats utterly frustrating. I'm reading its battery, SD, firmware problems..Nope its GoPro problems.

[derbo]

Time to take charge of the situation

I knew that I wanted to replace my battery since I got the car but I never got around to it. The primary reason for the lack of motivation was because the car was always on the tender when parked in the garage and I never seen any issues with discharging over the few days I drive in a row.

Initially, I wanted one of the antigravity batteries but I think at the end of the day I didn't really need to save that much more weight for $800+.

From the forums, I've seen others use a Z4M 70Ah battery so I went to my local dealership and got a 70Ah AGM battery.

Part no: 61-21-5-A40-E19 (This is the new part number that supercedes the original Z4M 811 part number)
Weight: 45lbs
CCA: 680

The battery I pulled out my car was a 90Ah 900CCA battery. For those who have OE batteries in their car, the negative terminal shows a date in the format of WW/YY. Mine was 15/10 which meant April 2010, over 608weeks ago! Who else has their original battery from 2010?!

Anyways, the original battery was 60lbs so there was net loss of 15lbs due to the smaller CCA and group size. As you can see in the picture, it is definitely smaller!





Installing was uneventful:

I coded 70Ah AGM into the CAS module
Synced time with my laptop via ISTA
Registered the new AGM battery via the barcode and mileage

Tada!

I'm still amazed that AGM battery survived for so long.

[DanMpower]

Very cool Derek, curious about how you secured the smaller battery?

The OEM bracket that holds down the battery is made for a group 49/H8 behemoth. Are there additional slots that I never paid attention to?

[derbo]

Originally Posted by DanMpower

Very cool Derek, curious about how you secured the smaller battery?

The OEM bracket that holds down the battery is made for a group 49/H8 behemoth. Are there additional slots that I never paid attention to?

If you look at the installed picture, you can see the multiple threaded holes on the bottom. I believe there are 4 threaded holes for sizes H5 to H8 in there.

[DanMpower]

Originally Posted by derbo

If you look at the installed picture, you can see the multiple threaded holes on the bottom. I believe there are 4 threaded holes for sizes H5 to H8 in there.

Ooh that's what I was assuming but never looked. Good stuff