Camber changing massively under load

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se7ensport
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Camber changing massively under load

Post by se7ensport »

Hello

Recently got into auto solo's and have been doing pretty well, I'm running 3 degrees negative camber but still seeing all of the front tyre wear on the outside 1/4-1/3rd of the tyres.

I'm definitely suffering from under-steer and in the wet found I get about a 5% improvement by disconnecting the ARB (in the dry it works the other way), will adding a tower brace reduce the angle change I believe that I am getting?

Thanks
Alex

stylussprinter
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Re: Camber changing massively under load

Post by stylussprinter »

se7ensport wrote:Hello

Recently got into auto solo's and have been doing pretty well, I'm running 3 degrees negative camber but still seeing all of the front tyre wear on the outside 1/4-1/3rd of the tyres.

I'm definitely suffering from under-steer and in the wet found I get about a 5% improvement by disconnecting the ARB (in the dry it works the other way), will adding a tower brace reduce the angle change I believe that I am getting?

Thanks
Alex
Firstly , what tyre pressures are you running ? and which tyre ? What front spring rates lbs and shock settings ? I never used 3 deg negative even before running high lbs spring rates plus ARB ---- 2.7 NEG was as high as I've ever used and that's going through corners at Goodwood almost flat in 4th and 5th at 8000rpm. With 285lbs front -- 250lbs rear the last 6 or 8 years and only 1/4 clicks front --- 1/2 clicks rear shocks plus 14 psi , I still only running 1.9 neg ---- this gives me totally even tyre wear without understeer. Autotesting shouldn't need anywhere near my neg settings , past or present. I did mount a tower brace two years ago which brought the optimum neg setting required down to 1.9 after testing from 2.2 neg.
Sounds to me like too low tyre pressures front to get tyre wear of that pattern using 3 degrees neg ----- you shouldn't be moving fast enough to need it in Autotest.
I just love the Stylus but she keeps swallowing £££ !
Alfa Red 159 2.4 jtdm ti 260bhp 365lbft / BilsteinB12 + Adjustable Powerflex camber/castor bushes. Red STYLUS 2lt zetec 231bhp 185lbft Dunnell . RED 1972 Alfa 2lt GTAm replica 170bhp.

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Re: Camber changing massively under load

Post by se7ensport »

Weekend was soaking wet, my set up was Yoko A539s with a starting pressure of 35psi, front springs are 240, rear 180, 1 click on the front, 2 on the rear, ARB disconnected.

Autosolos are notorious on outside tyre wear as its often full lock to full lock.

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se7ensport
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Re: Camber changing massively under load

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Re: Camber changing massively under load

Post by stylussprinter »

se7ensport wrote:Weekend was soaking wet, my set up was Yoko A539s with a starting pressure of 35psi, front springs are 240, rear 180, 1 click on the front, 2 on the rear, ARB disconnected.

Autosolos are notorious on outside tyre wear as its often full lock to full lock.
539's aren't the best for turning on the nose grip but 35psi is way too high , especially on our lightweight cars. I'd start at 20 psi plus ARB in the dry and gradually drop the pressure to find the optimum. In really wet condition disconnect ARB as you did then increase PSI between 2 to 4 psi above your optimised dry psi.
Shocks wise , I'd start at 2 to 3 clicks front ( as you have high lbs springs) then 6 to 8 clicks rear ( springs being VERY soft)
A guide on shocks , not knowing your shock manufacturer , would be 1/4 total front clicks and 1/2 total rear clicks. Obviously you'll need to test and develop the optimum for your chosen dicipline , as my settings are optimised in another direction.
I just love the Stylus but she keeps swallowing £££ !
Alfa Red 159 2.4 jtdm ti 260bhp 365lbft / BilsteinB12 + Adjustable Powerflex camber/castor bushes. Red STYLUS 2lt zetec 231bhp 185lbft Dunnell . RED 1972 Alfa 2lt GTAm replica 170bhp.

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