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Old 09-03-2017, 04:12 PM   #1
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understeer on 17 brz

17 brz on the track. much easier to drive than the 16 FRS... rear end is much easier to control, but the damn thing understeers all over the place. especially downhill. had to use the brakes a lot to get it to turn in at any reasonable rate at all... what are some steps i can take to bias the grip up front a little more? stiffer rear antisway bar? the front feels almost underdamped... but wouldn't more damping on the front make the understeer worse?
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Old 09-03-2017, 05:17 PM   #2
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17 brz on the track. much easier to drive than the 16 FRS... rear end is much easier to control, but the damn thing understeers all over the place. especially downhill. had to use the brakes a lot to get it to turn in at any reasonable rate at all... what are some steps i can take to bias the grip up front a little more? stiffer rear antisway bar? the front feels almost underdamped... but wouldn't more damping on the front make the understeer worse?
Start with a performance alignment.

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Old 09-03-2017, 05:21 PM   #3
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I'm guessing you already left foot brake?

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Old 09-03-2017, 05:22 PM   #4
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Add camber up front. Changing springs and bars and dampers is a waste imo if you're not even using the whole tire you've got. Stock suspension I think I went up to 3.2 degrees and the improvement in grip was immense.

Technique will do a lot, newbies generally charge the corners too hard and create their own understeer, I have definitely done that. Instruction/tightening the nut behind the wheel can cure a lot of car setup problems.

The other trick may be pedal dance to improve trail braking rotation. After exploring those things I think a stiffer rear sway may get you the balance you want, but I'd chase alignment first, I was pretty happy with the balance with -3.0 degrees up front and nothing else.
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Old 09-03-2017, 05:52 PM   #5
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Add camber up front. Changing springs and bars and dampers is a waste imo if you're not even using the whole tire you've got. Stock suspension I think I went up to 3.2 degrees and the improvement in grip was immense.

Technique will do a lot, newbies generally charge the corners too hard and create their own understeer, I have definitely done that. Instruction/tightening the nut behind the wheel can cure a lot of car setup problems.

The other trick may be pedal dance to improve trail braking rotation. After exploring those things I think a stiffer rear sway may get you the balance you want, but I'd chase alignment first, I was pretty happy with the balance with -3.0 degrees up front and nothing else.
That was the other problem I was having. I couldn't get pedal dance on! Wtf! I read that it's the same procedure but I can't get min to turn on... Trying g to figure out what's wrong.the car was built July 17 according to a sticker.
Maybe I just need to get back in pedal dance...

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Old 09-03-2017, 06:12 PM   #6
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Trying g to figure out what's wrong.the car was built July 17 according to a sticker.
It MUST be warmed up. If you can't get it on next time, after your session shut the car off and immediately turn it back on and attempt pedal dance, I bet that's all it is.

BTW if you don't provide more details about your setup you've pretty much exhausted the amount of suggestions you will get.
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Old 09-03-2017, 06:54 PM   #7
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It MUST be warmed up. If you can't get it on next time, after your session shut the car off and immediately turn it back on and attempt pedal dance, I bet that's all it is.

BTW if you don't provide more details about your setup you've pretty much exhausted the amount of suggestions you will get.
Car was fully warm trying to get into pedal dance. I tried it before every session. And after a few. Couldn't get it any time. Wound up doing the 5sec Trac button. Track mode is really weird. Does weird shit that I don't understand. I didn't really need to brake much at streets so the brake bias adjust being on didn't bother me.

Car is fully stock aside from an oil cooler and some brake pads.

The other problem that day was they just put down a slurry coat at streets of Willow, so people were saying it's like driving on ice... Maybe it was just a bad day?

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Old 09-03-2017, 06:59 PM   #8
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Couldn't get it any time.

Maybe it was just a bad day?
Won't know unless you have video why it didn't go on. My only advice is you don't have to do it super fast, just do it deliberate, you have plenty of time, make sure you see the e-brake light go off when you go down, lift your foot all the way off the brake pedal.

Everyone has bad days, track conditions very well may be the issue, but you'll have to correct for it somehow so you have a good time when it happens again, 'cause nobody is going to hand out refunds.
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Old 09-03-2017, 07:05 PM   #9
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Won't know unless you have video why it didn't go on. My only advice is you don't have to do it super fast, just do it deliberate, you have plenty of time, make sure you see the e-brake light go off when you go down, lift your foot all the way off the brake pedal.

Everyone has bad days, track conditions very well may be the issue, but you'll have to correct for it somehow so you have a good time when it happens again, 'cause nobody is going to hand out refunds.
still had an amazing time despite the 110f weather.
Thanks for your advice. I actually had a blast fighting to get front grip. Quite a change from the last car which was fighting to keep from spinning. But I would like the car to turn in better. I'll take video trying to get into pedal dance and maybe you'll see what I'm doing wrong... I thought I had it down with the last car but I'm probably doing something wrong.


You know... I just thought... This one has the little oem wing... I wonder if that's the main difference I'm noticing. Maybe I should just get a splitter lol

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Old 09-03-2017, 07:24 PM   #10
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still had an amazing time despite the 110f weather.
Thanks for your advice. I actually had a blast fighting to get front grip. Quite a change from the last car which was fighting to keep from spinning. But I would like the car to turn in better. I'll take video trying to get into pedal dance and maybe you'll see what I'm doing wrong... I thought I had it down with the last car but I'm probably doing something wrong.


You know... I just thought... This one has the little oem wing... I wonder if that's the main difference I'm noticing. Maybe I should just get a splitter lol

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Hey on track, maybe those front end side fin thing works... :P let me know

But ya Brz tend to lack a bit of front end traction when you turn.
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Old 09-03-2017, 08:19 PM   #11
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I'm guessing you already left foot brake?

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No... Should I be?

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Old 09-03-2017, 08:35 PM   #12
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It transfers weight to the front while keeping power to the rear which should help induce oversteer. Or at least help reduce understeer.

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Old 09-03-2017, 09:20 PM   #13
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Old 09-04-2017, 04:42 PM   #14
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Reposition your camera to get your hands in the shot, seeing where the car is can be nice for critiquing lines, but if you want to get insight into what the car is doing you are showing about 1/3 of the picture.

Things like rough binary inputs, shallow or late turn in, too aggressive or not aggressive enough, or maybe you're babying it and doing everything in your power to manage the weight transfer and the car is simply not responding, it's incredibly tough to judge without at a minimum seeing what the driver is doing.
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