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Reducing understeer

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Old 09-20-2008, 07:33 PM
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houstonnw
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Default Reducing understeer

Just got back from TWS and my instructor suggested that I try left foot braking since I'm comfortable with it in my auto transmission daily driver.

Wow, all my complaints about a lag during turn in are gone. Applying throttle while releasing the brakes or using the brakes with part throttle really calms the car down.

Unfortunately just a little too much throttle gets me into serious understeer at mid-corner and track out.

So my question is, how can I reduce understeer without reducing rear, or more correctly, total grip?

- I already have CC plates.
- I could use wider front tires - no.
- I don't think that I could add a low enough front splitter to make a difference.
- Taking weight out of the front of the car is very very expensive.

It seems like sway bars are the only option. But don't sways just reduce understeer by throwing away rear grip? Or is that not such a bad thing on our front heavy cars?

The real question is, will tuning with sways have an overall effect of making the car faster?
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Old 09-20-2008, 09:39 PM
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RodeoFlyer
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there are a hundred things you can do -

what is your setup now?
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Old 09-21-2008, 01:26 PM
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houstonnw
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Originally Posted by RodeoFlyer
there are a hundred things you can do -

what is your setup now?
Koni SA's, MM CC plates with 1.8deg negative camber (max I could get), and Kuhmo 255/50-17 SPT's.

Well, that and my mAd sKiLLz.
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Old 09-21-2008, 01:55 PM
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RodeoFlyer
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A pro that helps me out has "never bought an aftermarket swaybar in my life".


The lack of camber seems to be a common complaint about the MM plates. With my KW setup I can get over 3.5

What is your toe set at? Can you afford to toe it out some?

You can drill your own holes in the factory front bar and free it up some. If you don't have a set of adjustable end links yet I would get a set of Strano's and at least get rid of the pre-load.

Have you played with your shocks? Soften the fronts and/or stiffen the rear.

Have you kept a log of your tire temps and pressures? Go up in the front and/or down in the rear if you can.

How much fuel are you running? When I started out I just thought the track got hotter as the day went on (it does), but then I realized DUH - by the later sessions I had burned off 100lbs of ballast in the rear. Toss your spare and jack back in too if need be.

The rule of thumb is to address the misbehaving end. Make all of the adjustments you can in the front. If it still pushes too much make adjustments in the rear.

Last edited by RodeoFlyer; 09-21-2008 at 02:32 PM.
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Old 09-21-2008, 08:21 PM
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jayel579
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Originally Posted by RodeoFlyer
You can drill your own holes in the factory front bar and free it up some. If you don't have a set of adjustable end links yet I would get a set of Strano's and at least get rid of the pre-load.
I have -1.9 degrees camber and I dont even have camber plates. Look into buying a set of camber bolts, Ford Part# 4R3Z3B236AB are the ones I have. Take out your struts and round out the bottom hole, using metal file by hand works best. If you look at your stock front struts you can see guide lines around the hole, kind of like parentheses around the hole for the bolt. Measure the distance those line are from the hole and round out your Koni's to that. I think you might be able to get to -3.0 degrees camber with your plates once you do that.

The end links help a lot also. I have has a handful of people autocross my car after I installed Strano's end links and they were all amazed at how well the car turns in.
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Old 09-21-2008, 09:03 PM
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Texotic
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what kind of event did you do? i'm thinking about doing one of the Driver's Edge events there next month. just did my first autox in over a year and it made me really want to do events more often.
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Old 09-21-2008, 10:17 PM
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houstonnw
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Originally Posted by Texotic
what kind of event did you do? i'm thinking about doing one of the Driver's Edge events there next month. just did my first autox in over a year and it made me really want to do events more often.
It was a HPDE or Track Day on the 2.9 mile course.

Both the TWS Motorsports Club and The Driver's Edge have events there. The Driver's Edge events fill up pretty quickly, especially for the Green or beginner's group, however I think that the Motorsports Club has gotten pretty close in terms of professionalism.

I do mostly Motorsports Club events because they let me do Saturday only, which works for my schedule a little better.
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Old 09-21-2008, 11:51 PM
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ndgoalie35
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Upgrade the rear swaybar and leave the front one alone. I put an extreme anti roll bar from Griggs on my rear end and it significantly reduced understeer.
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Old 09-22-2008, 11:18 AM
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Hello, we offer a solid 7/8" rear sway bar. The bar also has new urethane bushings and billet end links. We also have the extreme anti roll bar which is intended for reducing body roll for drag racing applications. If you have any questions about our products please give us a call.

http://www.bmrfabrication.com/2005Mustang.htm
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Old 09-23-2008, 08:38 AM
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I'd try a set of Vogtland springs and leave the sway bars alone, while making the shock adjustments noted above (rear firmer, front softer). Of course, YMMV.

But why not just call Sam Strano and ask him? He can set you up with what you need.

www.stranoparts.com
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