What am I doing wrong?

Discussion in 'SN95 4.6 Talk' started by Silverstang02GT, Mar 30, 2009.

  1. Silverstang02GT New Member

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    I have a set of 26x10.5 15 M/T ET Streets that I put on when I go to the track. no mater how much i heat them up I still seem to spin off the line and also in 2nd a little. not as much as street tires but they still spin. the best 60' time that I have gotten with them was a 1.978. I read all the time about people getting 1.6 and 1.7 60's. I sure would like to knock .3 -.4 tenths off my time. that would put me around 8.2 - 8.3 in the 1/8 mile.

    I run anywhere from 17 to 20 psi and launch at about 4500 rpm

    Maybe all my car is capable of is 1.9 - 2.0 60's with my mods. which are:

    BBK shorty headers, BBK O/R X pipe, 40 series Flowmaster Mufflers, FRPP 3:73 Gears, Steeda Tri-Ax shfter, 80mm C&L Mass Air Meter & Inlet Tube, 75mm Acufab TB & Plenum, Professional Products Typhoon intake manifold, Granatelli Coils, Steda Under Drive Pulleys, Diablo Sport Tuner.
  2. Nitrous03GT New Member

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    start by going to 15psi and also play around with the revs at launch, start at 2500 and go from there..you should be able to pull 1.7 easy, i pull 1.9 on street tires without much issue..
  3. 1badsilver99 New Member

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    its the shorties....... :rolleyes: haha but yea just takes practice.....
  4. SaleenGT2001 New Member

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    drop the air pressure.

    i run 12-14 psi on my ET street RADIALS
  5. Silverstang02GT New Member

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    here are a couple of launch shots I grabbed from a video. 1st one is at the light the next is just after. both from the same run.

    [IMG]
    [IMG]
  6. kyle_99gt Member

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    you dont need a helmit at ur track?
  7. Silverstang02GT New Member

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    no. it is an 1/8 mile. plus i'm slow
  8. Nitrous03GT New Member

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    dang. the 1/8th tracks here in chucktown are pretty lax, you can click off 7's all day long with no helmet, but the minute you put any kind of slick(even ET streets) they go apeturds and make you have a head condom on.

    edit-

    looks like the pressure is way too high, should have more wrinkle in the sidewall.
  9. Winters98GT Founding Member

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    track prep probably sucks.

    are you running steel wheels with those tires, or are the black pro stars?

    I would lower to pressure to 12-14psi.

    You might want to look into aftermarket control arms and getting that rear end beefed up.
  10. Gearbanger 101 SuperMod

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    That's funny, I run mine at 32psi and they dead hook every single time.

    Silverstang02GT, are they ET Streets, or ET Street Radials? You might want to actually try bumping up the pressure. If they're buckling in the middle, you're probably reducing your contact patch more than improving it. Also, there’s no reason to "overheat" drag radials. Get them going until they start bellowing smoke out the wheels wells and drive out of it. Should be nice and tacky.

    Also, if they're a little worn, they might need a little more heat.
  11. Silverstang02GT New Member

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    They are mounted on Diamond cut type 50/51 15x8 Ultra. they(wheels) weigh about 22lbs



    they are the ET Streets and have about 20 to 25 runs on them.
    next time I'm at the track I will play around with the psi some.
  12. bwahl602 New Member

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    drop the tire pressure
  13. SaleenGT2001 New Member

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    :eek:i had mine at 30 psi at first and was getting a TERRIBLE swaying in the rear of the car. it was SCARY to go WOT in 3rd b/c the car was all over the road. i dropped the pressure to 18 and it's been fine ever since
  14. BurningRubber Active Member

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    What was your MPH?

    It looks like it's leaving hard, the front end is coming up alot.
  15. 04GTMustang New Member

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    its all about working that clutch. i got a 1.65 out of NITTOS and they didnt even chirp off the line. all i do is rev it to 4500 light goes green and as i am slipping the clutch i am applying more throttle. i was at wot before the clutch was even out but it was done pretty quickly too. it just takes practice man.

    just get out there and practice practice practice.

    and i hated my nittos when i first put them on but once i figured them out they were not as bad as people say.
  16. bhuff30 Founding Member

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    I completely agree with you, slip the clutch and it takes a lot of practice. I've gotten a 2.00 60' using those useless factory goodyear tires that came on the 99+ GT (on the 88 though).

  17. Silverstang02GT New Member

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    I'm trapping about 82mph and the ET's are 8.6's
  18. Silverstang02GT New Member

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    See thats what I keep hearing. the best I got out of my street tires is a 2.4 60'.
    I never really slip the clutch though. I'll work on that and see if I can better the 60'
  19. bhuff30 Founding Member

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    When I launch on street tires, I normally bring the revs to around 3000-3500, depending on how good the track is. When the 3rd yellow comes on, I let out the clutch a bit to start putting a bit of power down, but be gentle at first, it is easy to overpower the tires on the initial hit. Then once you are moving slightly, you want to smoothly let the clutch out and feed it more gas if the track can handle it. My perfect launch will normaly hold the rpms constant at I let the clutch out. It will hold 3500 during the launch, then fully engage the clutch at around 3500, then gas to the floor and run out first gear.
    A sign of a good launch style is if the tires start spinning AFTER the initial hit. That just means you were too aggressive with the clutch or gas as you slipped it. I've gotten plenty of street tire 2.1 60' times spinning the tires through 1st. The trick is to get off the line cleanly, which gets a bit of weight transfered, so even when it is spinning, it is still powering forward.
    Of course, your combination will like different launch rpms. The trick is just to apply the power smoothly. Start very softly with plenty of rpms and then you can start engaging the clutch and giving it some gas.
  20. 98COBRA281 Active Member

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    my best 60' on 275-40-17's street tires was a 2.07...........

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