WAY Too Much Oversteer, Help Me Sort it Out
tehehehe
10-26-2011, 12:01 PM
#22
OP, what are you doing for front sway bar mount reinforcement? If you're still on stock un-modded mounts, you don't really have a front sway bar, you just have some ballast that connects both sides of the front suspension.
I'm running almost the exact same suspension bits, though my Konis are set 1/2 turn from full stiff front and 3/4 from full stiff rear, my ride height is a little higher in the front and I'm running 550/350 springs on the GCs, and no rear bar at all. My car is very neutral to mild understeer past the limit. After buying tires, try pulling the rear bar off if you're still not happy.
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10-26-2011, 12:30 PM
#24
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Vehicar beat me to it. Estock cars also cram 225 A6's on 6.5" wheels. Not because they can....because they have to. I'll wager not a single competitive CSP,STS,SSM,EM,STR,XP or DP Miata runs more camber in the rear. That being said.....new tires and a rear "air" swaybar should fix most of the problem.
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10-26-2011, 12:30 PM
#25
miatas run more negative camber in the rear on stock suspension all the time.
Its not ideal, but it works fine. tbh on stock suspension the most my guy could get was 1* in the front, I am certainly not going to turn my rear down to .7-.8* and say its better than the 1.5* I can get.
Its not ideal, but it works fine. tbh on stock suspension the most my guy could get was 1* in the front, I am certainly not going to turn my rear down to .7-.8* and say its better than the 1.5* I can get.
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10-26-2011, 02:28 PM
#28
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There is no reason that car should be so tail happy. I've autoxed on 450/350, spec bars, and 205 azenis and spanked *** with 230whp and a torsen t2r. You have something wonky and I am guessing its in the rear. Was the driver who drove your car the kind of guy that slides his car? Your other car is awd? You might just be a big *****
Tires.
what tire pressures did you run?
what tire pressures did you run?
Your springrate spread seems reasonable, but these alignment numbers are interesting.
In the turbo car, I always ran more negative camber in the rear than the front, (in the red car I was at -1.5F, -2.0R) and from what I've read, this is typical for both autocrossers and "spirited" street drivers. Makes for a very predictable car- neutral throttle into a corner produces a little understeer, which you can correct for with throttle.
Most of the folks I have seen running more negative camber up front are from the trackday crowd.
In the turbo car, I always ran more negative camber in the rear than the front, (in the red car I was at -1.5F, -2.0R) and from what I've read, this is typical for both autocrossers and "spirited" street drivers. Makes for a very predictable car- neutral throttle into a corner produces a little understeer, which you can correct for with throttle.
Most of the folks I have seen running more negative camber up front are from the trackday crowd.
Car is too low. You're deep into the bumpstops while cornering. The spring rates are dominated by the bumpstops. If you're deeper in the bumpstops in the rear than the front, you get oversteer. Especially power oversteer, which makes the rears squat and increases bumpstop rates even more.
To test this theory, raise the rear 1/4 " and report back.
To test this theory, raise the rear 1/4 " and report back.
I Didn't reach in and check to see if the bump stop was pushed all the way up. How does this look?
OP, what are you doing for front sway bar mount reinforcement? If you're still on stock un-modded mounts, you don't really have a front sway bar, you just have some ballast that connects both sides of the front suspension
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10-26-2011, 02:34 PM
#29
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FWIWI. I ran konis with 500/300 springs, a 7/8" front bar on full stiff, and a stock rear and I had WAYYYYYYYYYYYYYYYYYYY too much push. I couldn't autox the setup because I couldn't rotate the car.
That shot without the tire... is that at droop?
Also, that that spring isolator allowing the bump/shock to travel all the way through?
This one removed more than an inch of bump travel.
That shot without the tire... is that at droop?
Also, that that spring isolator allowing the bump/shock to travel all the way through?
This one removed more than an inch of bump travel.
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10-26-2011, 02:35 PM
#30
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List of things to do. Correct the order if necessary.
1 Remove rear sway (Already done) May reattach later for track days.
2 Tires
3 Raise rear ride height 1/4" (pending review of actual ride height.)
4 Address possible reversal of F&R camber.
One thing at a time and review results. Anything else?
1 Remove rear sway (Already done) May reattach later for track days.
2 Tires
3 Raise rear ride height 1/4" (pending review of actual ride height.)
4 Address possible reversal of F&R camber.
One thing at a time and review results. Anything else?
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10-26-2011, 02:51 PM
#33
List of things to do. Correct the order if necessary.
1 Remove rear sway (Already done) May reattach later for track days.
2 Tires
3 Raise rear ride height 1/4" (pending review of actual ride height.)
4 Address possible reversal of F&R camber.
One thing at a time and review results. Anything else?
1 Remove rear sway (Already done) May reattach later for track days.
2 Tires
3 Raise rear ride height 1/4" (pending review of actual ride height.)
4 Address possible reversal of F&R camber.
One thing at a time and review results. Anything else?
I would also move tires up to #1 and the rear sway disconnect to #2.
Tires are your contact patch with the ground, doesn't matter what else your car has on it, if they suck then your car sucks.
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10-30-2011, 07:22 PM
#35
List of things to do. Correct the order if necessary.
1 Remove rear sway (Already done) May reattach later for track days.
2 Tires
3 Raise rear ride height 1/4" (pending review of actual ride height.)
4 Address possible reversal of F&R camber.
One thing at a time and review results. Anything else?
1 Remove rear sway (Already done) May reattach later for track days.
2 Tires
3 Raise rear ride height 1/4" (pending review of actual ride height.)
4 Address possible reversal of F&R camber.
One thing at a time and review results. Anything else?
1b look at brains post and remove that chunk of rubber if it's in there. If it is, then for sure you won't need to do #3.
regardless of your tires, you should be able to get the frt/rr balance the way you want. *all old tires will do is have less grip, but it will be at both ends unless you have newer tires up front.
* remember the part about never say never? well, usually when going to stickier tires, i've noticed a slight propensity towards understeer. but it's usually just a little and easily adjusted with shock settings or tire psi. Not the same as whats happening to you. fwiw, when i first got my miata, i had massive oversteer at the auto-x too. the list above will make a huge impact on it and bring it under control considerably. also, i run the exact opposite camber too! ymmv
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10-31-2011, 02:53 PM
#39
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All your input is appreciated. I'm supper busy and won't be able to dig any deeper for a week or so. I'll try to get some changes done before the next autox on the 19th. I will report back with results.
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10-31-2011, 03:21 PM
#40
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I'm going to say it is *possible* that Brain's isolator issue and the Koni's being highly aggressive with the rebound might be a Daily Double™ combo breaker keeping you hard on the rubber.
+eleventy New tires will just hide the imbalance so that it only happens at a more dangerous speed. You would be far safer finding the deficiency first, whatever it may be.
It's a shame you can't mount a video camera in a position that would capture the suspension movement in action. Or can you?
It's a shame you can't mount a video camera in a position that would capture the suspension movement in action. Or can you?
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