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Loose steering at speed

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Old 03-19-2008 | 11:31 AM
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Default Loose steering at speed

Anyone have a fix for this? My car (99 C2, w/ aftermarket Aero 1, orig fact 17" wheels, Goodyear F1 all season) steers beautifully at normal speeds. I have had a couple opportunities to get the car up over 90+ mph (also had a full tank of gas), and the steering is a bit twitchy and loose, not nearly as planted as I would prefer. I get little or no vibration, so I'm thinking the tires are properly balanced. I'm looking at larger wider wheels right now, and will fit them with sumer tires. Maybe that will help a little also.
Right now, I won't be driving down the Autobahn at 150 anytime soon, it would be terrifying.........

Mitch
Old 03-19-2008 | 11:43 AM
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Do you have the front lower lip installed?
Old 03-19-2008 | 12:24 PM
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If you have the rear wing you need the deeper front spoiler. Alignment is also suspect, the settings are fragile and can be knocked out easily. Car should be rock solid at speeds of 150 MPH.
Old 03-19-2008 | 12:25 PM
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I'm adding the GT3 Cup front splitter to mine. Looks very subtle in photos, and supposedly helps.

I'm assured that the lightness in the front end is not as bad as it feels, but I'll be glad to settle it down a bit.
Old 03-19-2008 | 12:30 PM
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Suspension may need to be replaced. I just replaced mine and it made a huge difference.
Old 03-19-2008 | 12:31 PM
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Check tire pressures also.
Old 03-19-2008 | 04:47 PM
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My tire pressures are 34F 34r for 17" tires. My front bumper has an aftermarket GT3 piece, and it has the lower lip added into the general molding. I took a measurement and the front center clearance is 6 1/4", the back edge (right before the wheel) is 5". So it tapers from the front, downwards. Is this correct? Stock ride height. I'll get a pic of it, and show you guys what I mean that the "lip is integrated with the bumper". Looks a bit ****ty to me, maybe I should spring for another bumper, and will do so if this is causing problems.
Old 03-19-2008 | 04:49 PM
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Running that low of tire pressure will cause all sorts of handling problems. Your car probably wants to wobble too. Get you back tires up to above 40 psi.
Old 03-19-2008 | 04:54 PM
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Originally Posted by 1999Porsche911
Running that low of tire pressure will cause all sorts of handling problems. Your car probably wants to wobble too. Get you back tires up to above 40 psi.
+1 There is a sticker on the car with the tire sizes and pressure. I recall its 36F 44R with recommended tire sizes.
Old 03-19-2008 | 05:02 PM
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This is what I was talking about- the add on "lower lip" is actually part of this piece!

Attachment 264753

Attachment 264754

Attachment 264755

Last edited by 6ocyclehum; 04-28-2008 at 05:31 PM.
Old 03-19-2008 | 05:04 PM
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Really? It drives and handles fantastic at normal speeds. Seems like higher pressures would make things worse at high speeds. I'll give it a try though. So 36F and 44R is where to start, correct?
Old 03-19-2008 | 05:48 PM
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You have an aero with the correct "lower lip." I have it. I would check alignment and tire pressure. How's your susupension?
Old 03-19-2008 | 06:04 PM
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Originally Posted by chsu74
+1 There is a sticker on the car with the tire sizes and pressure. I recall its 36F 44R with recommended tire sizes.
This is incorrect. 36F 44R is only for the 18 inch wheels. He has 17inch.
Old 03-19-2008 | 06:09 PM
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Originally Posted by Gaspasser19
This is incorrect. 36F 44R is only for the 18 inch wheels. He has 17inch.
^^Nice username.
Old 03-19-2008 | 06:16 PM
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Originally Posted by ArneeA
^^Nice username.
Thanks. I have a dream job, I pass gas in my pajamas all day.

Back on topic, I just checked the bible and it says 17"- 36psi F&R.
The 17" wheels may be part of your problem. I felt a huge improvement in higher speed handling when I upgraded to 18" wheels.


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