I was wondering if anyone changes there tire pressure before going to the track. If someone could help me out thanks!
YES. makes a huge difference. i went 15.4 @ 24PSI and 15.8 @ 30 PSI. it makes a huge difference in the grip you get off the line
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Jimmy cox wrote:I was wondering if anyone changes there tire pressure before going to the track. If someone could help me out thanks!
Yes it does make a difference.
FU Tuning
also, lower tire pressures reduce wheel hop (try bouncing a half flat basket ball, dont work to good does it? same applys for tires)
also use a tire that has some sidewall to it, low profile tires are not good for track use, i use a 15" rim with a drag radial on it (has some sidewall) and works wonders... a 14" rim would do the job possibly even better.
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But side effect to lower tire pressure is that you will have a slower mph.
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boostedeco wrote:But side effect to lower tire pressure is that you will have a slower mph.
True, but you have to find the sweet spot for traction. Normally if you have good traction your MPH will be off, but with no traction = higher MPH lower higher ET.
FU Tuning
Thanks i had a couple of people tell me that it made your et worse by lowering tire pressure i thought they were wrong
You can certainly make them worse if you lower it too much. It's all about finding the RIGHT tire pressure for your setup.
Would there be a point in doing the back wheels?
I put just under the max allowable pressure in the backs for less rolling resistance.
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Yes lemme tell you my best run running max pressure on the 1/8th was 11.2 after lowering front wheels to 25 I got a 10.8 and I still got wheel hop so I think I could do better if I find the "Sweet " spot.
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the rule of thumb is
whatever max pressure is, say its 44psi for my stock garbage tires... I would put it at 45psi
the reason being is it makes the tires as round as they can get, thereby reducing rolling resistence
for the fronts, you drop pressure slightly
now this is where you need to experiment
I tried dropping my pressures to get a better e/t, but ended up gettting worse times... I managed to drop my 60' to a 2.2 but my ets when from 15.7s to 16.1s
just experiment at the track... run 2-3 runs at a pressure, checking it inbetween runs to make sure temp hasn't changed pressure, then change pressure, and run another 20-3 runs... in the same day preferrably
I know its not easy because tracks tend to be packed, but it does work
its a fine line between gettin the whole footprint on the ground and not deflating them too much. i would say deflate ur tires until the whole tread is touching the pavement. kinda hard to explain.
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1/4 mile... low front... high rear
autoX ... high front... low rear
what psi to put... trial and error my friends
the MPH times you will see from a tire thats supposed to have 32psi dropped down to 22psi will be minimal at best.
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** Flat Broke Racing Inc.**
my 60' times running about 18-20 psi of boost were 2.4 on 32 psi of tire pressure. 2.181 was the best running 22psi tire pressure on my stock RSA tires. Yes pressure makes a difference. just don't drop it too much or you'll risk tire damage or loss of control. My personal safety margin on street tires is 20 psi ot tire pressure. You can probably go lower, but personally, I wouldn't because I'd rather err on the side of safety.
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'Nuff said
10psi in the tires got me a 1.82 60ft
. Next time I will try running around 12psi in the tires to see if I can get a higher mph.
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I was gonna say ask adler and look at his recent thread, but he beat me to it. AND, Yes it does make a difference.
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don't forget...if you lower a street radial's tires pressure too much...it can have a reverse effect also. It can cause cuping which will cause you to loose traction. The trick is to find the right psi for your tires. not too high...and not too low.
i dropped mine to 25 psi and i get a hell of a launch
