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 Post subject: Re: FWD suspention help
PostPosted: Tue May 21, 2019 11:02 am 
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Joined: Fri Nov 13, 2009 9:12 pm
Posts: 1379
Location: Cbus, OH
Take the front bar off, up the front springs (I'd suggest 800lbs), up the rear camber to -2.5 degrees, and stop running the S75 on the front axle. That compound is way too soft for your car, so it's turning to goo and not responding well at turn in, and then once weight transfer actually happens, you're probably riding on the outer inch of the outer rear tire as its contact patch rolls over, causing it to oversteer at mid-corner. Are your shocks single adjustable Koni yellows, or what? I'd turn those up in the rear too. I think your pressures seem fine, if anything I'd lower the rear a psi or two. You have a nose-heavy, long wheelbase, moderately powered FWD car like I do. The goal is to allow the front end to work and react quickly, with a compound you're not burning down, and a rear end that will transfer weight, create a high lateral load on the rear tires, and allow the contact patch of the tire to move and basically catch it.

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Kevin - ruckracing - '15 & '10 Runoffs FP Champion
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 Post subject: Re: FWD suspention help
PostPosted: Tue May 21, 2019 12:15 pm 
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Joined: Sun Dec 14, 2014 11:06 pm
Posts: 128
Location: Portland, OR
Is the rear steer functional? A quick google search and it looks like it does the typical out of phase at low speed and in phase at high speed. The in phase will be creating understeer. If this is happening in turn in, and you’re fighting it by putting in more and more steering that could cause the sudden oversteer after everything catches up.

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 Post subject: Re: FWD suspention help
PostPosted: Sat May 25, 2019 9:35 am 
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Joined: Fri Dec 02, 2016 7:52 am
Posts: 49
The shock are the single adjustable yellow Koni's


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 Post subject: Re: FWD suspention help
PostPosted: Mon May 27, 2019 6:45 am 
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Joined: Sun Jan 23, 2011 4:54 am
Posts: 2223
there's yer problem!

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Matt Blehm
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 Post subject: Re: FWD suspention help
PostPosted: Mon May 27, 2019 7:12 am 
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Joined: Tue Dec 31, 2013 10:40 am
Posts: 488
Location: Huntsville, AL
Being strut front and strut rear is the problem. No doubt the roll centers and suspension geometry hasn't been optimized for the ride height of a Production Race car. That is contributing to all of these issues. Find a circle track shop with a pull down rig and help them figure out how to pull the car down and see what the suspension is actually doing in action. You might find a binding or other issue, plus you can analyze the camber and toe situation in "real time"

What do you have for bushings in the suspension?

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Brett W
Huntsville, AL


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 Post subject: Re: FWD suspention help
PostPosted: Tue May 28, 2019 9:58 am 
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Joined: Wed Oct 28, 2009 9:24 am
Posts: 996
To further Brett's input - have you maybe lowered it too much on one end or the other? Strut suspensions can start to do really weird stuff if lowered much past "lower arm level".

I was unaware of this when I first bought my VW race car ~20 years ago. Dropped the nose to what looked about right (based on experience with rwd cars with proper short long arm front suspensions) and couldn't figure out why it would not turn in worth beans.


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