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Old 10-26-2011, 09:43 AM   #21
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Some E-stock cars run more negative camber in the back, ones that have won nationals tehehehe


New tires and disconnect the rear sway IMO
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Old 10-26-2011, 01:01 PM   #22
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Originally Posted by flier129 View Post
Some E-stock cars run more negative camber in the back, ones that have won nationals tehehehe


New tires and disconnect the rear sway IMO
They also custom valve their shocks to lock the car down onto the bump stops so they can cheat their way into whatever spring rate they want, and other such tomfoolery. Stock class suspension mods almost never have any bearing on the real world.



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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Old 10-26-2011, 01:23 PM   #23
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Originally Posted by vehicular View Post
They also custom valve their shocks to lock the car down onto the bump stops so they can cheat their way into whatever spring rate they want, and other such tomfoolery. Stock class suspension mods almost never have any bearing on the real world.
Agreed, but TNTuba used the word never
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Old 10-26-2011, 01:30 PM   #24
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Quote:
Originally Posted by flier129 View Post
Some E-stock cars run more negative camber in the back, ones that have won nationals tehehehe


New tires and disconnect the rear sway IMO
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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Old 10-26-2011, 01:30 PM   #25
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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.
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Old 10-26-2011, 01:35 PM   #26
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Never say never!!

Lol
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Old 10-26-2011, 02:43 PM   #27
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Ok...you win your semantics debate. How does that help the OP with his non EStock car?
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Old 10-26-2011, 03:28 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 *****
Pussyism is very possible, thats why I asked for a second opinion. I'm not sure how he drives his car, only saw him drive mine. He drives a modded 280Z. Yeah my WRX is AWD, not hard to drive. I had it set up to be neutral at the limit, I could get it to rotate with a little LFB. (Learned that in Rally School)

Quote:
Tires.

what tire pressures did you run?
Before going I researched here and miata.net. I also asked other miata drivers at the autox. One guy said try 35 all around, I gave it a shot and wasn't impressed. I found my best times were at 32F 29R.

Quote:
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.
I got those #'s off of 949's alignment page. I've been building this car to start doing trackdays, so I went with their recommendations.

Quote:
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.
I made hasty measurements on my ride height, when I posted above. I may be closer to 12.5"F/13"R. Not at home to measure now, I'll do that later. I tried to follow the well established recommendations on ride height and rake that I found on these and other pages. And I have FCM top hats and shortened bumpstops, The car does not look slammed, so I assumed I'm good on that, perhaps not.



I Didn't reach in and check to see if the bump stop was pushed all the way up. How does this look?

Quote:
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
Stock mounts.
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Old 10-26-2011, 03:34 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.
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Old 10-26-2011, 03:35 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?
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Old 10-26-2011, 03:36 PM   #31
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Quote:
Originally Posted by Braineack View Post
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?
Photo is with tire, sitting on ground. 5 seconds after first picture was taken, just looking through spokes.
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Old 10-26-2011, 03:39 PM   #32
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okay, then yeah doesn't appear like you have tons of bump travel...see my spring isolator comment, I edited my post.
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Old 10-26-2011, 03:51 PM   #33
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Quote:
Originally Posted by dstn2bdoa View Post
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?
I would NOT reverse the F&R camber. you have it right.

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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Old 10-26-2011, 09:44 PM   #34
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Originally Posted by Track View Post
I would NOT reverse the F&R camber. you have it right.

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.
QFT. Believe it or not but a set of 90 run 275 35 15 A6's are worse than a fresh set of street tires.
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Old 10-30-2011, 08:22 PM   #35
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Quote:
Originally Posted by dstn2bdoa View Post
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?
1a soften rear shocks
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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Old 10-31-2011, 12:18 AM   #36
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I am still sticking to my toe in theory. Dial in about 1/32 of toe in and feel the difference. at zero, my car was really *** happy.
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Old 10-31-2011, 02:06 PM   #37
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that wouldn't make that big of a differnece. i'm at zero frt. and rr. and my rear is glued to the track. so are all the spec miatas in the country. your theory is fail.
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Old 10-31-2011, 03:09 PM   #38
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I think I'm onto something...
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Old 10-31-2011, 03:53 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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Old 10-31-2011, 04:21 PM   #40
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Quote:
Originally Posted by spoolin2bars View Post
1a soften rear shocks
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.

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Originally Posted by spoolin2bars View Post
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.
+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?
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