Tire Pressure. Which Car has it working and which doesnt?

Discussion in 'General Discussion' started by Nazirull Safry Paijo, Nov 21, 2015.

  1. Nazirull Safry Paijo

    Nazirull Safry Paijo Registered

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    Hi guys. Need to figure this one out. Are the cars with new CPM has the tire pressure working? ( i know i can test them myself but just trying to get a list here)
     
  2. Euskotracks

    Euskotracks Registered

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    What do you mean?
    Tire pressure works in all cars CPM and non CPM ones.

    Enviado desde mi GT-I9505 mediante Tapatalk
     
  3. Nazirull Safry Paijo

    Nazirull Safry Paijo Registered

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    There are cases where mid temp doesnt change no matter wut the tire pressure is
     
  4. Euskotracks

    Euskotracks Registered

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    What you describe is common to most if not all vehicles using ISI based tire model.

    But that does not mean tire pressure is not working. It just means it is not working properly in general.

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  5. Guimengo

    Guimengo Guest

    I have found the crowning issue to be much improved. The tires must still be run at extremely low pressure and considerably smaller negative camber for them to function well, but the crowning has improved.
     
  6. Nazirull Safry Paijo

    Nazirull Safry Paijo Registered

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    Thanks for the input :)
     
  7. David O'Reilly

    David O'Reilly Registered

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    Bottom line is that its not wise to chase (the theoretically correct) temperature spread to establish the best camber or tyre pressure because it doesn't work.
    If you chase the "correct " temps the performance will drop.
    Experiment with pressures and camber, find out what works best for you in terms of grip and feel.
    In my experience the middle temp will be in between the outer temps but much closer to the inner temp when the tyre is working well.
    The set that gives the best grip will also give the best wear.

    Empirical Temperature Data. Temps vary so much in the RF2 tyre model that at this moment its not easy to give an empirical view on optimum delta between for example inner and outer temps. Certainly the old adage that the middle of the 3 temps across the tyre should be the average (middle) of the outer and inner does not apply. It seems that with good (grip) camber settings the inner and middle temps are quite close and the outer edge temp much lower.
    The delta across the tyre can often be 30 degrees (mid rubber depth ). So we really are in a “suck it and see” scenario. Do not attempt with camber to get the middle temp to read as the average (middle) of the inner and outer temps as it won't work. It will be higher than that and much closer to the inner temp. EG 95/90/70. Edit recent tests (build 982) indicate that on good front camber settings on a rear wheel drive GT car a delta of 25 degrees across the tyre is normal.) .We suggest you adopt an “output approach”. IE Suck it and see
     
  8. Guimengo

    Guimengo Guest

    ISI is well aware of the tires. I think the mindset of middle temp being the average is long gone, along with the one that some people had a decade ago about inside-out/front-back being the same. I am curious to see what's in the works for whichever car is released/updated next and I am sure once there is time to be devoted, this aspect will be dealt with closer to a more permanent approach than "getting things to a functioning state."
     

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