Mike's 128i (HPDE & DD)

[blnk-128]

I'm happy to report I passed instructor training and had my first student this past weekend at Summit Point Shenandoah. It was a fun ride start to finish, a 2 wheel off moment and rotors with serious pad deposits kept me on my toes. By the end of the weekend we were rolling so much additional speed through big bend (a fast left hander) that my student thought we must be in a lower gear based on the rpms.

As a track Shenny has a real laid back atmosphere. It's in a quiet town, you get to camp next to the track, they've got warm showers and some of the best trackside food. The circuit itself is highly physical and given my gearing + intake I was shifting 9 times per lap. With the typical pricing for events here, it's a serious value for anyone in the DMV area. Here's my Catalyst onboard where I set a few PB laps in a row.

Onto the car. I finally installed the 328i brakes and let me tell you, the 2mm piston size increase makes a remarkable difference. Between that and some stickier tires, my understeer issues have been largely resolved. The Kumhos I picked up have been phenomenal as well. They have significantly more grip than the 615k+s, which I'll never run again. With 6 track days on the Kumhos the outer block is a slick but they still have at least 4 more days left.

They're temperamental on warm up, and need a lap or two to build pressures and temps into the sweet spot. Once there, the tires are remarkably consistent before falling off to slightly below their top pace. I've found 27-28psi hot is the sweet spot for pressure as indicated by the wear bars and overall feel. I haven't run them in the wet, and at this point I wouldn't want to.

I'll be back up at Watkins Glen this monday/tuesday and the weekend after that I'll be at Summit Point main. Would love to see some other 1ers out there!

[cerealwars]

Originally Posted by blnk-128

The Kumhos I picked up have been phenomenal as well. They have significantly more grip than the 615k+s, which I'll never run again. With 6 track days on the Kumhos the outer block is a slick but they still have at least 4 more days left.

They're temperamental on warm up, and need a lap or two to build pressures and temps into the sweet spot. Once there, the tires are remarkably consistent before falling off to slightly below their top pace. I've found 27-28psi hot is the sweet spot for pressure as indicated by the wear bars and overall feel. I haven't run them in the wet, and at this point I wouldn't want to.

Agreed on everything about the V730s! I went through a set start to finish on my Miata and I had the exact same impressions, even down to the pressure setting. Excellent tire. Glad to know they work on these cars too. They're not too expensive either.

You're looking nice and tidy out there! The carousel looks fun.

[blnk-128]

Was at the Glen this past weekend and figured I'd throw on some old HT-10s I had from my first track weekend 2 years ago. My thoughts were two-fold.

1. See if I felt a difference in car balance
2. See if I could feel them come into or out of their temperature window

I did this as I was wondering if the DTC-70s in the rear were falling short of their ideal temperature window. What I felt was a car that understeered slightly more, but did seem to get rear brake bite earlier into a session. End result is I'll keep running the DTC-70s.

As for the day itself, I'm massively quicker on the Kumhos compared to the Falkens. I showed a 2s a lap improvement, and that was with traffic. I never had the chance for a clean session as I was giving ride-alongs to family and my student the rest of the weekend.

Speaking of which, I helped my student swap his rear pads on his MK7 GTI when they wore down to the backing plate after 3 sessions. We went out again on day 2, and these new pads lasted all of 30 minutes. Looks like our BMWs aren't the only ones doing crazy stuff with traction control out on track.

Video in case anyone wants to use my lap as a reference.

[Brian_]

Originally Posted by blnk-128

Speaking of which, I helped my student swap his rear pads on his MK7 GTI when they wore down to the backing plate after 3 sessions. We went out again on day 2, and these new pads lasted all of 30 minutes. Looks like our BMWs aren't the only ones doing crazy stuff with traction control out on track.

Yep the MK7 leans on the rear brakes very hard trying to reign in understeer with the stability control on. Definitely surprising the first time to see the rear brakes burn up first in a car with 64% weight on the front axle until you realize what's happening.

[blnk-128]

I'm going down the LSD road and looking for feedback. More context/details in this thread: https://www.1addicts.com/forums/show...4#post30481214

[blnk-128]

Hey y'all, as the season draws to a close I wanted to encapsulate the 15 events I've done this year and the continued development of the car. I've been seeing more and more 128s and 328s on track as people realize the platform's potential, and I've seen a variety of setups.

While these forums are "dead", what is dead may never die, and I want to thank everyone who participates or has helped out via a DM. It's been great meeting Spidertri, AMG6975, Phloozy, and others who have been generous with their time, information, and experience.

Power
This year saw the addition of significant modifications, let's start by reviewing everyone's favorite category -- Mo Powah Baby! ~20k miles later I'm happy to report the N54 intake & headers combo has been a revelation. While I haven't put the car on a dyno, I would estimate a minimum 35hp increase over factory. On track it lives between 5k and 7.5k RPM, being near the top of that range multiple times per lap, every lap. This results in high oil consumption, but overfilling before an event and topping up every other session has proven effective thus far. My concerns over longevity are easing with time and on the street it consumes 0 oil, so at least I have that benchmark going for me. My top speed on the back straight at VIR was 134.6MPH at ~40degrees.

Braking
Woahing this all down are new to me F30 335i front and E90 328i rear calipers. To start with the cons, these add a fair amount of unsprung weight mainly due to the front rotor size increase. In my setup they also added understeer, though I suspect that wouldn't be the case if you stripped the interior and/or went to a semi-slick tire. That being said, these things are consistent as hell thanks to their massive thermal capacity, which also removes the need for any brake ducting. The pads are lasting 5-6 events for me compared to the 1-2 I was getting on the stock setup. With FCP Euro carrying Hawk DTC-60s for the fronts, I saved more than my cost of installation this year alone. They also look cool, at least before they're covered in brake dust. If you're tracking on a budget I cannot recommend this pairing enough.

Seating
Let's talk restraints. To whoever buys my sport interior when I decide to pull it out, I'm sorry. The Schroth Quick-Fits are invaluable for staying contained in the seat and allowing for a Hans, but as a consequence they are beating the s**t out of the cushioning. To anyone HPDEing more than 2x a year these are worth their weight in gold despite the wear and tear. As my speeds and risk increase, I'm beginning to think that this current setup may be insufficient safety wise in the event of a rollover. Quick fits cannot be used with a true bucket seat, so if I upgrade to a roll bar I'll likely move on to a 5/6 point harness.

Suspension
Suspension time. I feel as though the TC Klines are overwhelmed in both damping and spring rate. I'm running 300# front springs and 600# rears as I originally thought this would be a good compromise between street and track. It was sufficient in the beginning but cannot keep up with the increased demand being placed on the car via modern 200TWs. In the rear I'm experiencing secondary motions when dealing with surface bumps, leading to oversteer. The front was rolling past it's ideal geometry, so adding an E92 M3 front sway bar was necessary and counterintuitively reduced understeer.

While TCK offers 400# front springs and 700# rears, based on my knowledge this would increase understeer as the relative stiffening is more front biased. It would make sense that I could go back to my stock FSB since the M3 one is effectively increasing front spring rate, but that would also place more load on the dampers which are already maxed out. Additionally, I've never been able to achieve over 2.8 degrees of front camber with TCK camber plates and M3 front control arms. The spherical bearings in the plates have worn out, so I'll need to replace those or consider moving to the Vorschlag plate which people seem to have more success with. Again the car is getting around the track as configured, so this setup has been effective. As I continue to progress I'm looking for more handling performance, so any suspension recs are appreciated.

Wheels and Tires
Are you tired of buying tires? This year I went through 3 unique sets of 200TWs, the Falken 615k+, Kumho v730, and once again the Continental ECFs. I've reviewed them a bit, so I'll summarize the main points here. The Falkens were not a good time on this car, being the slowest and fastest wearing, albeit most forgiving. They are the cheapest but I would spend a little more to get the Kumhos. They offer excellent grip and life in the dry, but take a bit longer to warm up and hydroplane often in the rain. The ECFs run super wide as I previously mentioned, but running the 245 on a 9" wheel made a huge difference in sidewall stability and outside corner wear. They are excellent bang for buck, giving you a true all weather endurance 200 similar to the RS4. The M3 FSB looks to have increased tire life by 2-3 events per set, if you're not doing this mod for the grip do it for your wallet!

Offseason Plans
The last major gripe I have with this car is the lack of an LSD. I've purchased a Wavetrac carrier that I'll try to install myself, and I am hoping that will add the last bit of functionality I need for HPDE. When driving other people's cars on track, I've found I’m not well adjusted to the driving dynamics of having an LSD and so I view it as essential to my skill progression. Other than that, the only "mod" on the horizon is adding some rear toe arms to help maintain rear alignment. For maintenance, she needs a new power steering line, shift shaft seal, spherical bushing replacements for the camber plates, a new windshield, and if she's lucky a new front bumper. I also should get around to installing the Condor baffle kit for the oil pan.

Future Goals
Right now I'm not exactly sure where I want to take this build. It's been a fantastic HDPE/DD, and over the last 5 events the only money I've spent has been on gas, oil, and one set of rear pads. A big part of me enjoys driving to and from the track and getting to let friends drive it around on the street.

Any leaps in performance will cost me either financially or in practicality. If I get a roll bar, it'll hurt my ability to put things in the backseat. If I add stickier tires, I'll need a new suspension and a baffle kit to prevent oil starve. If I want bucket seats, I'll need a roll bar. And if I want to race, I'll need to do all the above and a whole lot more.

So for right now I’m content to leave my car largely as is. Having a stable platform should allow for near apples to apples comparisons to gauge my improvement as a driver. By no means do I think I'm anywhere near my personal capabilities, and money spent on mods is probably better spent on coaching and seat time. That is until those Black Friday deals hit and next thing you know the car is at Piper getting a full cage.

I'll leave with a video showing my fastest lap at VIR this year, a 2:15.10, an 8+ second improvement from the year before.

[spidertri]

That's one heck of a lap, very nice.

Going through 4/5 are you WOT the whole time? I always end up throttle steering through 5 a little bit to get it tucked in for the lower esses.

I definitely need to commit to more throttle up the esses, my best lap I'm only around 100mph at the top, so there's time there for sure.

Great meeting you at the track, and the lead/follow laps were awesome, definitely need to do it again next year.

[blnk-128]

I'm lifting through the right hander after 4 to prevent the car from oversteering, and again as I turn in for 5 to get the nose to tuck in. The uphill esses are something, I had to intentionally practice lifting later and later and still know I have a few mph to go.

[Ric in RVA]

Originally Posted by blnk-128

I'm lifting through the right hander after 4 to prevent the car from oversteering, and again as I turn in for 5 to get the nose to tuck in. The uphill esses are something, I had to intentionally practice lifting later and later and still know I have a few mph to go.

Uphill esses are intimidating..

One day I followed some kid in a poorly driven viper up the esses in my spece30....and ended up towards the top going way faster than ever before.....

Looked at the flag stand and pitched it in over the blind brow and skittered out to track right.....whew......pucker!!!!



Love that track!!!