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