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      11-15-2024, 03:32 PM   #1
Adcampo
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Boy, track day will put a hurten on your tires.

They have plenty of tread left, they just aren't smooth. Picked up a bunch of melted rubber too. I've driven the car normally since and it cleaned them up some.
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      11-17-2024, 01:04 AM   #2
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Track marbles come off so don’t worry.
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      12-03-2024, 03:53 PM   #3
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How does this tire look? Can it still reach max performance or it shouldn't be tracked again?

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      12-03-2024, 06:12 PM   #4
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Quote:
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How does this tire look? Can it still reach max performance or it shouldn't be tracked again?

Stock PZ4

Attachment 3614128
That thing still has plenty of life left. At least another day or two. At $400 per, I’d squeeze ever mile out of them.
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      12-03-2024, 07:01 PM   #5
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That thing still has plenty of life left. At least another day or two. At $400 per, I’d squeeze ever mile out of them.
Thats good news. Otherwise $2000 tire cost each track weekends is forbidding
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      12-04-2024, 04:22 PM   #6
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Quote:
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Thats good news. Otherwise $2000 tire cost each track weekends is forbidding
I’ve got 11k miles and 2 track days.
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      12-05-2024, 11:17 AM   #7
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How does this tire look? Can it still reach max performance or it shouldn't be tracked again?

Stock PZ4

Attachment 3614128
You can track any street tire to the cords. You'll just start to notice after multiple heat + cool down cycles that your braking distances will get longer and your car will understeer more and get more tail happy on trail braking.

Unless you're shooting for ultimate lap times, you can run them until you wear them out. They just won't be quite as fast.
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      12-05-2024, 09:13 PM   #8
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You can track any street tire to the cords. You'll just start to notice after multiple heat + cool down cycles that your braking distances will get longer and your car will understeer more and get more tail happy on trail braking.

Unless you're shooting for ultimate lap times, you can run them until you wear them out. They just won't be quite as fast.
I do want to push for better lap times so if I can feel the tires start slowing down I probably just go for a new set.

Interestingly trail braking on these cars almost never push the rear end outward. I had wished there were more rotation on corner entrance, but if I brake just slightly more, the car understeers more. Not sure this has anything to do with 4WD mode.
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      12-06-2024, 09:58 AM   #9
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Quote:
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I do want to push for better lap times so if I can feel the tires start slowing down I probably just go for a new set.

Interestingly trail braking on these cars almost never push the rear end outward. I had wished there were more rotation on corner entrance, but if I brake just slightly more, the car understeers more. Not sure this has anything to do with 4WD mode.
Need all the assists off to get the rear to move a bit but so far, I've been faster entering corners a little slower and on power super early. I think it's too obese for acrobatics.
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      12-06-2024, 10:14 AM   #10
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Quote:
Originally Posted by vrships View Post
I do want to push for better lap times so if I can feel the tires start slowing down I probably just go for a new set.

Interestingly trail braking on these cars almost never push the rear end outward. I had wished there were more rotation on corner entrance, but if I brake just slightly more, the car understeers more. Not sure this has anything to do with 4WD mode.
Looking at your video, I think you are trail braking too much and trying to rotate the car on the front axle, at least on some of the corners. The overall weight of the car is not necessarily the issue. The car has 53% of its weight on the front axle, so trailing the brakes all the way to the apex or even past it is not the best technique with front-engine cars. That overloads the front outer tire and you get understeer. Trail the brakes less, just enough to ensure the attitude of the car entering the corner is to your liking, and then momentarily pause with feet off the pedals, essentially coast, until the attitude of the car gives you confidence of your corner exit, then get on throttle gradually, but aggressively. Rotate the car on the rear axle.

This technique is not valid for every corner, but IME works well for medium- to high-speed corners. Also, this technique can offer some unwanted surprises on the rear axle in 4WD Sport, having the car in 4WD as you have works really well with this technique. I can feel the front axle pulling the car out of the corner with the rear rotating in a predictable manner.

Finally, as a word of clarification, that momentary pause I mention above is critical to ensure the chassis is settled on outside wheels before transitioning from braking to throttle. It makes a world of difference. That momentary pause is just fractions of a second or half of a breath, just enough to settle the chassis.

I hope this helps in some way.
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      12-06-2024, 10:58 PM   #11
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Thanks a lot for all this extensive explanations.

I have struggled to get the car to rotate before the apex on almost every corner. And I feathered out my trail brake much earlier than what I did in simulators. But I am a first timer and this is the only car I tracked so maybe I didn't really catch the feel of rotation.

Anyway, as you can see I got the car under steered almost starting from the entrance for most corners, but usually not bad enough to miss the apex. And I think I released brakes fully before most apex. I realized the car slows down rapidly mid-corner, likely due to this constant under steering, if coasting, so I usually apply some light throttle before or at the apex to fight this slowing down. That makes the car feel like 4 wheel sliding from apex to exit, if I got it properly.

I need to practice more fine adjusting the trail brake on this car. Overall I am guessing I trail braked too light initially but held it for too long.
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      12-07-2024, 10:21 AM   #12
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Quote:
Originally Posted by vrships View Post
Thanks a lot for all this extensive explanations.

I have struggled to get the car to rotate before the apex on almost every corner. And I feathered out my trail brake much earlier than what I did in simulators. But I am a first timer and this is the only car I tracked so maybe I didn't really catch the feel of rotation.

Anyway, as you can see I got the car under steered almost starting from the entrance for most corners, but usually not bad enough to miss the apex. And I think I released brakes fully before most apex. I realized the car slows down rapidly mid-corner, likely due to this constant under steering, if coasting, so I usually apply some light throttle before or at the apex to fight this slowing down. That makes the car feel like 4 wheel sliding from apex to exit, if I got it properly.

I need to practice more fine adjusting the trail brake on this car. Overall I am guessing I trail braked too light initially but held it for too long.
I am glad I could be of some help.

With any car, it takes a while before you can feel the dynamics, which is very different than simulators. Give yourself time, and don't chase lap times. Lap times will come eventually. What is important, IMHO, is being able to run consistent lap times, not the ultimate number. Experiment with different techniques, there isn't a single way of driving, find your own way of getting the most out of yourself and the car.

One thing I would recommend strongly is attending autoxes. You will get to feel the car and yourself very rapidly

Have fun.

Edit: I also think that based on your brake pad wear, you are not using your brakes the most efficient way. You probably need to start braking a bit later approaching a turn while on a straight line, but with more force (try to actually break the brake pedal... you won't be able to ), gradually come off the brakes as you turn in and don't trail as much.
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Last edited by BackOnBlack; 12-07-2024 at 10:42 AM..
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