2013 Blacktrax Performance Thunderhill bypass config track day

[Z K]

I went out for the first time running the bypass config of Thunderhill yesterday. Blacktrax hosted an excellent track day with a lot of fast cars (mostly S2000s) and nice people.

My lap times weren't very great but I had a good time and my lap times dropped a good 5-6 seconds from beginning to end. The best I got was a 2:19... which is pretty slow compared to most fast laps in the M3. For comparison I ran a 2:11 in the Evo X running the same track config. I tend to run slower in Bypass config vs Cyclone config. In Cyclone config, I got a 2:17 in the M3 and 2:09 in the Evo so about 2 seconds slower. Kinda scary going over that blind crest so I brake there.

Looking at my fastest lap, I can see all the places I am braking too much or not on the throttle. Lots of things I can improve as well. The biggest thing for me is getting more confident in getting on throttle when it isn't straight. I always run with no traction control. I spun out at Thunderhill my last track day into the dirt so I try to be more careful now... It's my only car so I need to get home and be able to drive the car to work the next day.

Anyway, here's the video:

Below are my lap times. As you can see, getting better throughout the day. Still need a lot more seat time... and balls.

[OC3]

Nice. Glad to see that you made it thru T9 downhill uneventfully this year.

[Z K]

Originally Posted by OC3

Nice. Glad to see that you made it thru T9 downhill uneventfully this year.

Haha, you remember my last time going off!

After that off, I lift there to prevent that from happening. I can feel the car get light in that section. I'll stay neutral throttle until it settles back down and then WOT again. I see tire marks going off the course there so I know I'm not the only one to have that happen to them.

[OC3]

Originally Posted by Z K

Haha, you remember my last time going off!

Oh yeah, cuz a bunch of us in SoCal were planning a Thunderhill-Infineon-LagunaSeca trip when I saw your video. When we ran Thunderhill in June, I made sure I eased over that hill, hah.

Originally Posted by Z K

After that off, I lift there to prevent that from happening. I can feel the car get light in that section. I'll stay neutral throttle until it settles back down and then WOT again. I see tire marks going off the course there so I know I'm not the only one to have that happen to them.

Hah, yeah, the motor is mighty quiet this time while going down that hill.

I think you can stay on throttle if you just unwind the steering wheel and track out to the left side of the track. If and when I go back, that's what I'm planning to do.

[Z K]

Originally Posted by OC3

I think you can stay on throttle if you just unwind the steering wheel and track out to the left side of the track. If and when I go back, that's what I'm planning to do.

A lot of people do that. Let it track left and then bring it back right to make the corner. I need to work on that.

[OC3]

^

[admranger]

Looks like fun. I've only been to T-Hill once, for a club race weekend in 2009 in my J-prepared (non-aero though) E36M3 (w/2.8 motor, cams, injectors, exhaust, NT-01s, PFC-06's, 2990lbs w/driver). Oh, and I found out later after I sold the car that the tune was wrong and I had left 25hp on the table...

We ran the bypass the second day, the cyclone the first day. First weekend ever at T-Hill.

I checked my times (on the BMW CCA CR website) and my best time was 2:04.84 for the bypass. Of course, I had a trailer to push the car into if I wadded it up so I understand the need to drive the car home bit.

With your data acquisition, you should be able to see where your g-force curve isn't shaped like a "T" and work on those areas (as well as not coasting so much). Using all the track will help too. The E9x is a handful to tame as I have found out, so keep at it and build up in small increments. Don't try to do it in one bite, or you'll likely get bit!

[mot]

nice video! are you using euro mdm?

[Z K]

Originally Posted by mot

nice video! are you using euro mdm?

I have the traction control off.

[Z K]

Originally Posted by admranger

I checked my times (on the BMW CCA CR website) and my best time was 2:04.84 for the bypass. Of course, I had a trailer to push the car into if I wadded it up so I understand the need to drive the car home bit.

With your data acquisition, you should be able to see where your g-force curve isn't shaped like a "T" and work on those areas (as well as not coasting so much). Using all the track will help too. The E9x is a handful to tame as I have found out, so keep at it and build up in small increments. Don't try to do it in one bite, or you'll likely get bit!

I am definitely leaving time on the table. As OC3 commented about, I spun off into the dirt at about 90mph at Thunderhill last time which was not fun at all. I'm working my way back up in bravery and also getting used to the car more.