Originally Posted by dogbone
As SuperLap Battle at COTA approaches this weekend, I've been trying to get all my ducks in a row.
The weather is looking really good for Saturday and decent for Sunday. Phew.
On the technical side, I spent a lot of time trying to come up with an action plan for the car's issues. At COTA, my car was doing weird things. The rev limiter would rotate around the tach and restrict the revs and then move back out of the way and the car would run normally, but then it would jump down again...... the car would hesitate while on the gas at random times. But none of the codes were related to the engine or transmission. The errors were pointing more to DSC/ABS issues.
In looking at the codes, several people said the front wheel speed sensors looked like culprits. And the wheel speed sensor codes kept coming back after clearing the codes. So, something is up there. I've ordered brand new wheel speed sensors for both front wheels. (In the past, I have had some limp mode issues that pointed to the wheel speed sensors. When we replaced them, the issues seemed to go away.) I have to accept the fact that it gets ridiculously hot in my front hubs. I could see sensors going bad due to extreme heat.
Another thing we found was that half the gas tank had fuel in it, and the other half was empty. The fuel didn't seem to be siphoning between the halves very well. I don't know if that's specifically related to COTA, or something else, but I just replaced the whole fuel pump setup a couple months ago preventatively. (After the fuel pump replacement, it ran totally fine at Buttonwillow and 99.9% fine at Willow Springs, but I did have one tiny hesitation at WSIR.) So, we thought maybe putting more gas in the car would help that. And on Sunday, the car ran fine for the first couple sessions when fully fueled. But then, the revving issues returned even with a full tank. So frustrating.
Then, another mechanic/racer said that he's seen issues that look like this being related to the gas pedal going bad----that gas pedals in BMW race cars go bad more often than you'd think......he said they used to keep three gas pedals in the trailer when racing an E92 M3. Well, after that conversation, I was watching the 2:22 lap video that I posted here, and I was looking at the Turn 16,17,18 section, and as I enter that carousel, the data overlay shows that I get off the gas completely-------except that the car is accelerating and you can hear that I am CLEARLY on the gas.......In all the years of using an AIM, I have never seen that. I wondered, did RaceRender render the data on the video incorrectly? Nope. When you look at the AIM data, there's just no gas pedal activity captured at that moment, but I am definitely on the gas......hmmmm. According to the mechanic, the gas pedal sends signals to more than one place. So, he's saying it is possible that the car is responding to my pedal press and accelerating, but the CAN data could be incorrect and causing problems. So, I've ordered a new gas pedal.
When I get to Austin on Friday, my first set of tasks are to replace the wheel speed sensors and the gas pedal. I've watched videos and both tasks look very reasonable. I hope these things can alleviate the issues I was having. Whatever is going, it's intermittent and weird......and soooooo frustrating.
I'll have two new sets of slicks with me. I plan on running new tires at the start of each day.
I was debating whether to play the video game anymore now that I've been to the track. I took almost a week off of the game, but decided over the weekend to start back up. I've been getting faster in the game in the last day or so. I'm much more consistent in the game now. Having both the game to play and my own videos to watch has been giving me some new insights into the track. I am very eager to see how that plays out.
One of my Unlimited Class competitors introduced himself to me at the Chin event. Very nice guy. He ran at SLB Buttonwillow in November and won the Street class with his Subaru. He said that he had watched my videos of Buttonwillow and they helped him get a sense of the track. Cool. For this event, he's going to be driving his 991 GT3 (that has a Cup Car suspension). He's local to COTA and says that he has upwards of 10000 laps there. I believe it given the lap times he's doing in that GT3. I watched a video of him at the Chin event on new Michelin slicks doing a 2:17 IN TRAFFIC. He thinks the car can do 2:14. Amazing. Anyway, the garage assignments were announced and it turns out we are sharing a garage at SLB, so that's cool.
As this is my 50th birthday weekend, my family will go to Austin on Saturday to celebrate my birthday and hang at the track for a bit. In eight years of going to the track, my family has only been once and they stayed for about 15 minutes and took off. I don't anticipate them spending much time at the track this time either....I mean, they're welcome to stay.....I just know my wife will get bored with the whole track thing very quickly.....hahaha.....That's ok.
As far as looking at potential results, there's 8 cars in Unlimited. I think the podium is a long shot for me. Again, I have to compete against AWD cars, so that's tough. The Lyfe Motorsport Nissan GTR will be there. They did a 2:07 last year. Yup, I'd say that's good for first again. If the GT3 can do a 2:14, I think that has a good shot at 2nd. That leaves 6 cars shooting for 3rd (none of them local to COTA)......a Subaru STI, a GT3RS, a Lyfe Motorsport Nissan 350Z, a Honda Accord, a Ford Festiva, and me. Of those 6, my wild guess is that the STI is probably the quickest. I found it on YouTube. It's fully built. Heck, maybe it can do better than a 2:14. But COTA is tricky. It doesn't just hand out fast lap times out to newcomers. (I don't know if the STI has ever been to COTA.)
Anyway, the podium is not my main concern. I said before, my goal is to simply go sub-2:20. If the car is healthy, I am optimistic. Someone mentioned recently to me that no E9x M3 has done sub-2:20 at COTA. Is that true?
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