Running my 1st TT event tomorrow @CMP

[R13]

After a few years picking my way through the NASA HPDE ladder, I decided to go ahead and jump in to something where a quick lap actually means something.

I'll be running TTB and I expect to get crushed by a lady in a C5 Vette, and maybe have a close run with another fellow in a spec racer of some type.

This should be entertaining either way.

 

[itrsteve]

After a few years picking my way through the NASA HPDE ladder, I decided to go ahead and jump in to something where a quick lap actually means something.

I'll be running TTB and I expect to get crushed by a lady in a C5 Vette, and maybe have a close run with another fellow in a spec racer of some type.

This should be entertaining either way.

Congrats! How many points do you have to spare running in TTB? What mods are being tallied up?

 

[R13]

As it turns out, I've ended up with only 6 points to spare.

The main reason is that the car weighed in at 2926 (with me in it) which is 120 or-so lbs under the base weight of 3047 (as stated in NASA's classification). other point-bearing mods are the tires, tailpipe, coilovers, swaybars, and chassis brace.

After Day 1, I'm sitting in 2nd behind aforementioned chickinavette, although I'm closer than I thought I'd be. She's sitting on a 1:47.2xx. My fastest time of the day was a 1:48.6xx, but that didn't count because I spun on the next lap....spectacularly I might add. So my quickest scored time is a 1:49.2. The track got slower for everyone after the second session of the day, so I'm planning accordingly for tomorrow.

As a side, note, I should have some entertaining video from the second session. If anyone wants to know what backwards looks like at ~110mph, I got ya covered.

 

[docjohn]

how many cars compete in the tt events? Is it mixed in with regular hpde or is the whole day tt? I used to compete in emra tt but just like auto x got to be too tedious waiting around for my runs.Back then we did'nt have transponders so the tt was run like an auto x 3 laps per car,needless to say having over 50 cars was kinda hurtin.

 

[R13]

Schedule-wise it's like a competitive DE session. Practice session on day 1, then you get gridded by speed after that to minimize the need for overtaking. ~4-5 15 minute sessions/day.

It definitely hasn't been tedious so far.

 

[itrsteve]

As it turns out, I've ended up with only 6 points to spare.

The main reason is that the car weighed in at 2926 (with me in it) which is 120 or-so lbs under the base weight of 3047 (as stated in NASA's classification). other point-bearing mods are the tires, tailpipe, coilovers, swaybars, and chassis brace.

After Day 1, I'm sitting in 2nd behind aforementioned chickinavette, although I'm closer than I thought I'd be. She's sitting on a 1:47.2xx. My fastest time of the day was a 1:48.6xx, but that didn't count because I spun on the next lap....spectacularly I might add. So my quickest scored time is a 1:49.2. The track got slower for everyone after the second session of the day, so I'm planning accordingly for tomorrow.

As a side, note, I should have some entertaining video from the second session. If anyone wants to know what backwards looks like at ~110mph, I got ya covered.

That's still a pretty solid time. Unfortunately with CMP the best way to shave off a second or two is sacking up at the kink (which is something I can't do). I had a bunch of buddies there this weekend, I probably should of went.

 

[R13]

Yeah, about that "sacking up" at the kink:

skip to ~9:55 or so, lol.
<iframe width="640" height="360" src="http://www.youtube.com/embed/MoQLel7YFAo?rel=0" frameborder="0" allowfullscreen></iframe>

 

[itrsteve]

Yeah, about that "sacking up" at the kink:

skip to ~9:55 or so, lol.

You should of heard my audible gasp. Did you lift? That part of the track is such a mindf*ck that you have to tell yourself to keep the foot planted to the floor although common sense says otherwise. That kink has taken out many of cars, glad you were able to keep it under control and traffic behind was clear.

I lost it there in standing water my last time there, the guys at race control said I did 5-6 360's all the way down the straight, ended up a few hundred feet from the brake markers. It only further added to my fear of that thing.

I checked out two laps and everything looked great though.

 

[R13]

I asked myself the same "did I lift" question, but I've watched it and listened to it a few dozen times now and although I breathed the throttle before I turned in, I was neutral until after it let go. I've driven a mid-engined car my whole life, and I'm pretty certain I killed the "lift" reflex about 12 years ago, but it made me think.

I'm pretty sure I was going a couple miles/hour faster, lifted less, turned in earlier, caught too much curb on the inside, and hadn't un-wound the wheel. That and the left rear had gained too much pressure (~40lbs when I checked it about 2 minutes after the video stops, typically I try to shoot for ~35 hot), so really just a combination of things.

 

[ATERPAK]

From what you said about coasting through that section, possibly giving it a little more throttle as you entered the apex might have moved the weight to the rear just when you needed it and kept it going in the direction you wanted to go. However no matter the reason, I'm glad you're always testing your limits. That's the only way you'll be learning how to get faster while still under control and having fun. I rarely have a session where I'm doing everything right. In fact when I do, I'm probably going slow even though it all feels great. My biggest problem is using enough speed in the sweepers. I should be able to make up time there but often I'm just hanging in and not accelerating enough from the start to the finish of the sweeper. I just love to attack pure corners. It seems the more you do the better it feels and responds. I also noticed that once I changed over to my KW V3's I had a car that was just more responsive and grippy than ever before. I now have to learn a whole new car and move up to the next level. Hopefully I'll be up to the challenge.

Al

 

[R13]

Well, not exactly "coasting", just neutral throttle (not adding or taking away power). It's hard to tell, even in hindsight if accelerating there would have helped, hurt, or made no difference. I think the "bounce" from the curb was the primary factor here. I'd hit the curb there before in my MR2, but 10mph slower on much softer suspension, with slightly stickier tires and barely noticed it. Lesson learned I suppose, but as you say, now I know where that limit is....

 

[itrsteve]

I asked myself the same "did I lift" question, but I've watched it and listened to it a few dozen times now and although I breathed the throttle before I turned in, I was neutral until after it let go. I've driven a mid-engined car my whole life, and I'm pretty certain I killed the "lift" reflex about 12 years ago, but it made me think.

Not saying it works for everybody and may be totally different on MR, but I will either do a quick brake tap or throttle breathe before that curbing comes up and I make sure my foot is to the floor as I'm entering the apex all the way to the braking zone.

The car was definitely unsettled, I'm willing to bet that unsettling mixed with just a little bit of lift throttle caused that back to kick out just a hair.

This is where data would be really nice

 

[R13]

Yeah, I was running a phone logger, but it only samples 1x per second and obviously wasn't pulling any throttle/brake input. I might be able to get something from the accelerometer plot though. I'll have to take a look. While I would like to know exactly why, I'm not going to over-analyze it...that never ends well.

I'll see if I can get a graph in a form that's forum friendly.

 

[docjohn]

Big Al in the house:biggrin:

 

[R13]

Ok, I think this absolves me of lifting:

I've circled the "tipping" point there, and the longitudinal acceleration plot is trending upwards when the lateral G starts indicating turn-in, and maintains that trend until everything goes off the deep end.

 

[itrsteve]

Maybe it could be attributed to a stiff rear bar and dampers turned up in the rear after the unsettling of the kink? Not sure, if there wasn't lift then it would say it would deserve a degree of attention... that would scare the bejeezus out of me to happen each time if I were doing everything else correctly.

 

[R13]

I think I could've opened the wheel more on entry and it would've just been a wiggle, just watching it again that's what I keep telling myself to do from a critique standpoint. I do need to do some messing with corner balancing. It might not necessarily surprise me to find the rear bar is doing a little weight jacking.

 

[jtower]

slightly early turn in + a tad too much curb + teensy bit slow applying opposite lock. no big deal, everyone spins there eventually if they're pushing it.

to wit: https://vimeo.com/16028871 (go to 3:15)

for more fun at cmp, try this sometime: https://vimeo.com/11390110

 

[ATERPAK]

It almost looked like your tires were made of concrete or you had corded one of them. Certainly a handful around the track. Surprising how that soft thing called rubber can be pretty hard when it's pushed on the track. Good job until that last corner.

Al

P.S. Did the world seem to slow down during the spin? I'm trying to gauge what each driver sense during a spin to see if there is any consistency out there amongst drivers.

 

[R13]

P.S. Did the world seem to slow down during the spin? I'm trying to gauge what each driver sense during a spin to see if there is any consistency out there amongst drivers.

Yeah, I made a bunch of decisions and plans for when/where i might stop sliding...then just kinda waited for the car to slow enough to regain directional control. I mean it was a loooong slide, but I'd say there was a little mental time comprlession there....no "life flashing before my eyes" type of thing...I've spun cars before, but a little adrenaline shot for sure.