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Old 03-24-2017, 10:30 AM   #113
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People want specific front-rear grip balance. In most cases everything else untouched most are happy with a bit more grip in front vs stock, hence if you change grip bias with dialing extra negative camber only, most commonly suggested alignment is with more camber in front. One can play also with different coilover tuning / different rollbars / staggered wheel-tire setup to overcompensate camber choice of "other way around", but why? KISS principle still applicable, no?
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Old 03-24-2017, 04:24 PM   #114
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Originally Posted by Icecreamtruk View Post
You can, the thing is that you gain nothing from it. The car will understeer more, that is all. It all depends on what you want out of the car. Rear camber usually only gets you uneven tire wear and understeer, so people try to avoid it.
The reason why i asked becus my car tend to oversteer =[
i dont know if i go too fast or i throttle too early....
I have -3 camber front/ -2.5 rear
0 toe front, 0.05 toe in rear
255 tires
22mm front sway bar/ stock rear
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Old 03-24-2017, 04:45 PM   #115
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Originally Posted by FR-Sky View Post
The reason why i asked becus my car tend to oversteer =[
i dont know if i go too fast or i throttle too early....
I have -3 camber front/ -2.5 rear
0 toe front, 0.05 toe in rear
255 tires
22mm front sway bar/ stock rear
Rear camber is not static. It goes more negative with compression.

There's a difference between tendency to oversteer and power oversteer. If you have the car set up neutral, which I think you do, then it will be less forgiving of harsh driver input.

Also, that's a lot of rubber. Tire pressure will have a big effect.
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Old 03-24-2017, 05:22 PM   #116
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The reason why i asked becus my car tend to oversteer =[
i dont know if i go too fast or i throttle too early....
I have -3 camber front/ -2.5 rear
0 toe front, 0.05 toe in rear
255 tires
22mm front sway bar/ stock rear
You may have too much rear camber, most stick closer to -2. Too much camber will reduce grip.

Spring rates and sway bar are likely the next steps to hook up the rear. Damper adjustments as well.
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Old 03-27-2017, 09:53 AM   #117
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Originally Posted by FR-Sky View Post
The reason why i asked becus my car tend to oversteer =[
i dont know if i go too fast or i throttle too early....
I have -3 camber front/ -2.5 rear
0 toe front, 0.05 toe in rear
255 tires
22mm front sway bar/ stock rear
Another bit of advice I can give you (that I was never given initially, and when I did heard about it, it didnt make much sense until later), sometimes, you think the car oversteers or understeers naturally, when in reality, its the drivers inputs that make it so.

So a oversteery car could be caused by driver inputs. So lets try to see if its true or not. When do you feel/experience the oversteer? On corner entry, mid corner (right before and during the apex), or on corner exit? Do you experience oversteer only after applying throttle?

A car that naturally oversteers will do so when you enter a corner, but without any throttle input. If the car oversteers only when throttle is applied (commonly known as power oversteer), then its usually drivers input, you are mashing on the throttle too hard or too soon, or both (usually both).

Last edited by Icecreamtruk; 03-27-2017 at 11:36 AM. Reason: clarification
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Old 03-27-2017, 11:26 AM   #118
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If the car oversteers only when throttle is applied (commonly known as power oversteer), then its drivers input, you are mashing on the throttle too hard or too soon, or both (usually both).
That's not necessarily true, a sub-prime alignment or suspension setup (springs, dampers, sway bars) can make that happen when it shouldn't. This car isn't the kind of car where you have to wait until the wheel is straight to apply throttle, but I've felt it set up that way, no bueno.

I had some rear toe-out on accident for awhile, the rear end would jump out when the throttle was applied. It absolutely wasn't the driver, it was the car.

But I think you're on the right path, driver induced handling issues are more common than anything else for us amateurs. Especially if the suspension is off the shelf by a reputable company (or OE).

@FR-Sky see if you can ride along with someone else on the same course, doesn't even have to be the same car as long as grip levels aren't too different, that can be eye opening. If there's someone you trust with lots of experience, they may be willing to sit with you as a coach and notice if you're making obvious errors or even drive your car and give feedback. It's easiest to do if you're at autox (low risk) but there may be opportunities at track days as well (SpeedSF has an autox setup at most of their events, should work well as a test n' tune).
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Old 03-27-2017, 12:29 PM   #119
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If your inputs are too harsh you can induce lift-off oversteer too. That's when you lift off the gas too abruptly, upset the car and the rear wheels want to kick out. If your driving is the problem, chasing a fix with alignment will only make the car worse.

It all depends on WHEN you get that oversteer. Is it in the braking phase? Transition? Apex? throttle application? or track out?
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Old 03-27-2017, 09:03 PM   #120
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Originally Posted by Icecreamtruk View Post
Another bit of advice I can give you (that I was never given initially, and when I did heard about it, it didnt make much sense until later), sometimes, you think the car oversteers or understeers naturally, when in reality, its the drivers inputs that make it so.

So a oversteery car could be caused by driver inputs. So lets try to see if its true or not. When do you feel/experience the oversteer? On corner entry, mid corner (right before and during the apex), or on corner exit? Do you experience oversteer only after applying throttle?

A car that naturally oversteers will do so when you enter a corner, but without any throttle input. If the car oversteers only when throttle is applied (commonly known as power oversteer), then its usually drivers input, you are mashing on the throttle too hard or too soon, or both (usually both).
Yes, it oversteer between mid corner and exit,,if I throttle the car swing and traction control kick in. The only time I can really throttle is when the car most straight.
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Old 03-27-2017, 09:07 PM   #121
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You may have too much rear camber, most stick closer to -2. Too much camber will reduce grip.

Spring rates and sway bar are likely the next steps to hook up the rear. Damper adjustments as well.
Yea...forgot to mentions, I have spring rate 6k f/r damper 5/8 from hard
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Old 03-28-2017, 09:51 AM   #122
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Yes, it oversteer between mid corner and exit,,if I throttle the car swing and traction control kick in. The only time I can really throttle is when the car most straight.
Hmm interesting that you mention traction control. Means that you have either VSC Sport or just normal (everything) active. The nannies come into action way before there is an actual need for them to intervene. Just for reference, I cant drive the car properly on track with them on because they dont let me trail brake, they dont let me on throttle early, they dont let me do anything that you normally want to do to be fast (late brake, early throttle, going over berms). So I would suggest taking them off and trying with it first, you might be feeling the wrong thing.

More into your setup, you seem to have adjustable dampers, so try soft in the rear and hard in the front (which seems to be oposite of what you have). As a rule of thumb with dampers, the softer you go, the more grip there will be, but the more roll you might encounter. So try way softer in the rear, and way harder in the front than your current settings, that should help.

I honestly think you are chasing a problem you "think" you have, but im not sure you do have an oversteering problem (looking at your spring rates, I cannot imagine a car with square spring be an oversteery car).
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Old 03-28-2017, 12:16 PM   #123
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Originally Posted by FR-Sky View Post
The reason why i asked becus my car tend to oversteer =[
i dont know if i go too fast or i throttle too early....
I have -3 camber front/ -2.5 rear
0 toe front, 0.05 toe in rear
255 tires
22mm front sway bar/ stock rear
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Originally Posted by Ultramaroon View Post
Rear camber is not static. It goes more negative with compression.

There's a difference between tendency to oversteer and power oversteer. If you have the car set up neutral, which I think you do, then it will be less forgiving of harsh driver input.

Also, that's a lot of rubber. Tire pressure will have a big effect.
What are you tire pressures? I think you should look into that. Unless your alignment is completely different to what you think it is or something else is really off, it's hard to imagine your setup being prone to oversteer if you car is anything like any other 86.

What brand dampers and settings? Which tires? Are the tires different front to rear? How are you determining that you have oversteer if traction is on? From experience, the TC tend to make the car understeer when it does kick in.
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Old 03-28-2017, 09:35 PM   #124
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What are you tire pressures? I think you should look into that. Unless your alignment is completely different to what you think it is or something else is really off, it's hard to imagine your setup being prone to oversteer if you car is anything like any other 86.

What brand dampers and settings? Which tires? Are the tires different front to rear? How are you determining that you have oversteer if traction is on? From experience, the TC tend to make the car understeer when it does kick in.

It is factory setting 35psi all around.
It is TEIN flex Z, indy 500 , 255/40/17 square.
When I turn the traction control will kick in, and it is hard to throttle unless the car almost full straight.
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Old 03-28-2017, 11:28 PM   #125
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It is factory setting 35psi all around.
It is TEIN flex Z, indy 500 , 255/40/17 square.
When I turn the traction control will kick in, and it is hard to throttle unless the car almost full straight.
Strange... How do you know the TC is not kicking in from too much understeer?

I've driven a similarly set-up car same dampers, similarly sized tires 255/35/17 RSR tires with 35psi cold all around -2.5 fron -2.0 rear camber and 0 toe front and rear. Stock sways front and rear, and it didn't have a oversteer bias. With your 22mm front sway I'd assume it would understeer much more than the car I drove. What are you ride height and damper settings?
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Old 03-29-2017, 02:05 AM   #126
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Strange... How do you know the TC is not kicking in from too much understeer?

I've driven a similarly set-up car same dampers, similarly sized tires 255/35/17 RSR tires with 35psi cold all around -2.5 fron -2.0 rear camber and 0 toe front and rear. Stock sways front and rear, and it didn't have a oversteer bias. With your 22mm front sway I'd assume it would understeer much more than the car I drove. What are you ride height and damper settings?
I know it is not kicking in from too much understeer becus i know my tail swing little bit and the TC try to save it.
Yes I do have 22mm front sway, and I thought it would fix it as well.
My ride height is Flex Z standard, 0.8 inches front, 0.7 inches rear.
Damper is from hard, front 5, rear 8.
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