Help, Tire pressure for 355

Discussion in 'Technical Q&A' started by alanhenson, Mar 21, 2004.

  1. alanhenson

    alanhenson Formula 3

    Dec 2, 2003
    I need some help guys. I have a 1999 355F1 Spider. It is running 18 inch HREs with Michelin Pilot 225 45 18s on the front and 265 35 18s on the rear. I took it out of the garage for a drive and the tire pressures were around 35psi. The tires have a max pressure rating of 51psi. I inflated them to 48 psi and the car feels a little out of control, like it slides a little. Doesn't feel confident. My question is, What is optimal?? Any experience?? Thanks fellas.
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  3. malibumk

    malibumk Karting

    May 14, 2002
    Malibu, CA
    Full Name:
    Mike Klein
    I've always done well srtarting with the factory recommendations....see the lable inside one of the door jams.
  4. rexrcr

    rexrcr Formula 3

    Nov 27, 2002
    Kalamazoo, MI
    Full Name:
    Rob Schermerhorn
    Yikes...way too high. You're reducing the contact patch at that pressure, less grip due to less mechanical grip on the pavement, less pliable contact patch to conform to surface irregularities. Plus, new tires have a break-in period to rid themselves of any mould release agent, figure about 50 miles +/-.

    Start with Ferrari factory recommended pressures, label in the door jamb, and owner's manual.

    Here's a link to my tire pressure and handling for track days article:
    Chassis Tuning Ferraris for the Racetrack
    Found under Resources, then Other, then Parts & Service on the top of each page pull-down menus. Also available here.

    Best regards,

    Rob Schermerhorn

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