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Lowering tire psi at the track?

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Old 08-05-2009, 06:30 AM
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Default Lowering tire psi at the track?

Does this help at all if I am running GS-D3's out back? Im hitting the track up tonight and wanna know if I should lower the pressure in the tires.
Old 08-05-2009, 07:03 AM
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It will help. I always like to start off with 20lbs in the tires and work my way down from there.
Old 08-05-2009, 09:17 AM
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In my experience, nothing helps GS-D3s. They are a
good street tire dry and wet, but lousy when you are
at a track riding on other peoples' cheese for the first
100'. Pressure, L/R weight bias, nothing ever got me
under a 2.0 60'.

Nice tires for what they are, but a drag tire ain't it.
Old 08-05-2009, 09:20 AM
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Originally Posted by jimmyblue
In my experience, nothing helps GS-D3s. They are a
good street tire dry and wet, but lousy when you are
at a track riding on other peoples' cheese for the first
100'. Pressure, L/R weight bias, nothing ever got me
under a 2.0 60'.

Nice tires for what they are, but a drag tire ain't it.
Great lol. Would I have been better off with my stock GS' out back?
Old 08-05-2009, 09:41 AM
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Originally Posted by Striker
Great lol. Would I have been better off with my stock GS' out back?
No. The stock tire on these cars was abysmal. GS-D3 will at least grip. Hey, just hope for that 2.0 60'.
Old 08-05-2009, 10:23 AM
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Any rough ideas of what I may run?
Old 08-05-2009, 10:58 AM
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how would anyone know have any clue what you would run when all you've stated is the tires you have?

car/suspension/power/transmission/weight would help...
Old 08-05-2009, 11:14 AM
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run em at 20 psi......and my fortune telling/gypsy neighbor just unexpectedly knocked on my door and says type 13.8 at 103 whatever that means...
Old 08-05-2009, 11:36 AM
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Gotta love the gypsies. The cars a M6 WS6, more or less stock with a SLP lid, ported and polished TB and a pro 5.0 shifter.
Old 08-05-2009, 06:01 PM
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Do not lower the pressure on street tires at the track. They will cup and you will actually lose traction. Try about 28 to 30 psi on the rear and 36 up front. No street tire is really going to hook on a prepped track. That's just how it is.
Old 08-05-2009, 06:12 PM
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I cut a best 1.84 on Riken Raptors when I ran street tires........
Old 08-05-2009, 06:59 PM
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Originally Posted by Dal1as
Do not lower the pressure on street tires at the track. They will cup and you will actually lose traction. Try about 28 to 30 psi on the rear and 36 up front. No street tire is really going to hook on a prepped track. That's just how it is.
20 psi is fine for street tires, i run my sumis at that everyday and it helps a lot. At 30 psi it will blow them off.
Old 08-05-2009, 08:37 PM
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I say 23-26 psi
Old 08-05-2009, 10:38 PM
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on the street my street tires hook insane amounts better at 36psi than 26psi. never been to the track, but when i go i won't be dropping the pressure.

also, are you giving cold or hot pressures? just for reference my tires set at 36psi cold will jump to almost 45 after a few autox laps. if you set them to 25 cold and then drive to the track and do a long burnout they may end up closer to 30 when you launch.
Old 08-05-2009, 11:27 PM
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Best run was a 13.6 at 107mph. Kinda dissapointed. 60 foot was from 2.1-2.3 seconds.
Old 08-06-2009, 06:20 AM
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Originally Posted by therealcreeper
on the street my street tires hook insane amounts better at 36psi than 26psi. never been to the track, but when i go i won't be dropping the pressure.

also, are you giving cold or hot pressures? just for reference my tires set at 36psi cold will jump to almost 45 after a few autox laps. if you set them to 25 cold and then drive to the track and do a long burnout they may end up closer to 30 when you launch.
Normall psi is ok on the street. but i spun like i had 500 rwhp when i gunned it at the track at 35 psi. i released it to about 22-24 and hooked alot better
Old 08-06-2009, 08:34 AM
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Originally Posted by Striker
Best run was a 13.6 at 107mph.
Thats about right. maybe another .10 or two if you get used to the track.

Originally Posted by Striker
60 foot was from 2.1-2.3 seconds.
Normal

What did you end up doing about pressure? You owe it to your curiosity to experiment.
Old 08-08-2009, 07:13 AM
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[QUOTE=Dal1as;12024760]Do not lower the pressure on street tires at the track. They will cup and you will actually lose traction. Try about 28 to 30 psi on the rear and 36 up front. No street tire is really going to hook on a prepped track. That's just how it is.[/Q

^^^ BINGO
street tire--will cup
Johnny



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