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handling with new tires

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Old 04-28-2005 | 12:19 PM
  #16  
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Originally Posted by 944JM
Alright. The easiest thing then will be to reset the rear shocks the match the fronts. As for the tire pressure, the guy at the store runs the same on his VW and runs about 40 psi. The tire I believe on the side says a max pressure of 44psi. I currently have them at 38-40psi. How much difference will there be in handling if instead I set the front to 'stiff' also? I have new rubber bumpers to install for all of them so I might just consider doing the fronts instead if there is a night and day difference in the handling. The most notable turns for the fish tailing were 90 deg turns
Your initial post said you've upped the total grip with the new tires (corners faster), and now need to tune the suspension so it's once again balanced and confidence inspiring. Ideally, you go for the maximum grip that you can achieve at the front, then tune the rear to balance it for whatever conditions you're trying to optimize for (high speed sweeper entering a straight, etc.) As an example, firming the front shock setting might help with the balance, but lower the total grip utilization.....negative progess in terms of overall speed but a nice feel just the same.

Brian
Old 04-28-2005 | 01:23 PM
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With this in mind I think I'll lower the rears first and check the balance. That's the easiest thing to try first. What about the tire pressure? Leave it, check the ride, then up it and check again? So I take it these tires might like the softer setting as opposed to a more agressive compound?
Old 04-28-2005 | 09:43 PM
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Originally Posted by 944JM
With this in mind I think I'll lower the rears first and check the balance. That's the easiest thing to try first. What about the tire pressure? Leave it, check the ride, then up it and check again? So I take it these tires might like the softer setting as opposed to a more agressive compound?
Just simplify things abit and put the tire pressures back to stock F29/R36 and see what happens.
Old 04-29-2005 | 09:01 AM
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From: Winston Salem
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Don't tires have recommended pressures to ensure a good flat contact patch? Do the stock recommended pressures take into account aftermarket higher tech tires? I'll reset the rear shocks to match the fronts this weekend then sounds like playing with tire pressures. Anybody else have these tires on their 944?
Old 04-29-2005 | 09:23 AM
  #20  
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No they dont, pressures are determined by the manufacturer using the stock wheel/tire combo. The technology of the tires has little/nothing to do with PSI (in this equation).

Go to the stock setting and make adjustments from there. Like all upgrades, it will be much easier if you eliminate all variables ONE AT A TIME. I.e., make pressure changes first, then drive car. Make shock changes (if needed) with stock PSI, drive car. Then you can tune. Dont do both at the same time, you will never know what made the difference.
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Old 04-29-2005 | 09:25 AM
  #21  
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Originally Posted by 944JM
Don't tires have recommended pressures to ensure a good flat contact patch?
They have a maximum rating, nothing more. This same tire might be on a 4,000 pound car - stick to what Porsche recommends.
Old 04-29-2005 | 09:54 AM
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From: Winston Salem
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Will do. Thanks for the info!



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