Tire size for 1/8th mile

Discussion in 'Competition Camaros' started by Justin79maro, Oct 12, 2017.

  1. Justin79maro

    Justin79maro Member

    88
    1
    Jan 15, 2015
    Bonne terre, missouri
    I got 275/60r15 M/T street slicks on the back right now, was wondering if going to a 26" tire would help get my 60' down a little. ran a 1.81 60' and my 1/8th et was 7.9x @88mph. I have 3.42 gears and a 3,000 stall. I don't want to change the gears bc I drive it a lot on the street. I've only been down a track 5 times in my life so it's obviously a street car. I plan on doing CE drag shocks all the way around on it soon as well. Just want some input on these things first. Thanks guys
     
  2. mrdragster1970

    mrdragster1970 Veteran Member Lifetime Gold Member

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    What ever you can do to get a controlled spin off the line is the quickest!!!
    High enough to get up on the tire, low enough so you don't loose traction.

    You need to know what's going on now either with video or data information.
    Have you played with air yet, which way was quicker??


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  3. vegas1974z28

    vegas1974z28 Moderator Staff Member Lifetime Gold Member

    4,563
    73
    Jan 10, 2002
    Las Vegas,NV
    I don't think that's a "bad" 60 for that ET and MPH...it equates to about a mid 12 @109ish. Are you slipping off the line? If so I don't think a smaller tire would help you....It will change your RPM thru the trap. I agree with old man winter(above), play with the air pressure......mine loves 13 and hates 14psi
     
  4. Justin79maro

    Justin79maro Member

    88
    1
    Jan 15, 2015
    Bonne terre, missouri
    I played with tire pressure and it made no difference. I don't spin at all of the line as of now
     
  5. Justin79maro

    Justin79maro Member

    88
    1
    Jan 15, 2015
    Bonne terre, missouri
    Crossing the line I just shift into 3rd gear at 6,000 rpm. It doesn't spin at all but I would like to get it off the line a little faster
     
  6. SRGN

    SRGN Veteran Member

    189
    49
    Feb 20, 2009
    Central NJ
    If you're shifting to 3rd right before the traps you need numerically higher gears or a shorter tire if you can hook it. Since gear is out of the question, try the shorter tire.
     
  7. Justin79maro

    Justin79maro Member

    88
    1
    Jan 15, 2015
    Bonne terre, missouri
    I feel I go from a 28" tire to a 26" tire how much sooner will it shift? Cause now it shift at 88mph which is trap speed
     
  8. SRGN

    SRGN Veteran Member

    189
    49
    Feb 20, 2009
    Central NJ
    Should be 94 if everything else stays the same.
     
  9. mrdragster1970

    mrdragster1970 Veteran Member Lifetime Gold Member

    .


    Playing with air pressure is free. I hate wasting dough for no reason.
    If you think you're dead hooking now, then make an exaggerated pressure change.
    Go way down, see what happens. You may have to click early if it gets loose.
    Going way down makes less traction, increasing wheel speed, but also can be a handful at speed.
    If it starts to spin a little and you gain some wheel speed, and the 60 is quicker, then you know it was over tired.
    Go way up in pressure, and if 60 is quicker, then you know it wasn't hooking hard enough and you had too much wheel speed.

    If you think you're not spinning, try making it spin a little and see if you can get it under control.

    Like I've posted many many many many times, I'm always faster with a controlled spin than a dead hook.
    Trust me, with 34.5 x 17 x 16 slicks, it wants to dead hook more than it wants to spin.

    Good luck.

    .
     
  10. SRGN

    SRGN Veteran Member

    189
    49
    Feb 20, 2009
    Central NJ
    With a slower car, I don't think he'll see much difference. Especially on a radial, where you don't want to have the controlled spin we prefer on a bias ply slick with a lot more power. Wheel speed isn't going to be a major factor in the 12 second range.
     

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