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1 Jun 2003, 16:50 (Ref:616883) | #1 | ||
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street tire pressures
After a 20 year hiatus, I am thinking of doing a bit of autocrossing. I have a simple tire question as to tire pressures on my very stock Saturn SL2 (a small 2 litre, front wheel drive sedan for my friends in the UK!).
My tires are generic performance types. Size is 195 60 SR15. For low speed, low level competition, what kind of tire pressures would you recommend for front and back (in pounds)? Any advice would be appreciated! |
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"He's still a young guy and I always think, slightly morbidly, the last thing you learn is how to die and at the end of the day everybody learns every single day." - The Ever-Cheerfull Ron Dennis on Lewis Hamilton. |
1 Jun 2003, 19:37 (Ref:617056) | #2 | ||
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Depends a ton on the tire construction, but a good starting point would be in the 35-40 pound range. You'll then need to adjust according to temps, pressure rises, and sidewall scuffing.
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2 Jun 2003, 02:19 (Ref:617344) | #3 | ||
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Thanks MA2! The last set of tires I dealt with were a set of 155 SR 12's on a Ford Fiesta so these are a bit different.
Hope the driving isn't as "out of it" as my technical knowledge these days. Appreciate the help! |
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"He's still a young guy and I always think, slightly morbidly, the last thing you learn is how to die and at the end of the day everybody learns every single day." - The Ever-Cheerfull Ron Dennis on Lewis Hamilton. |
4 Jun 2003, 04:14 (Ref:620004) | #4 | ||
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Depends on the surface. I can run anything from 22psi (dirt) to 50-60psi (brushed concrete) on the front (185/60/13's). At the other end I would run 20psi to 30-35psi respectivly.
Its basically just eyeballing the tyre wear and going by the seat of the pants feel (or by the stopwatch). Suck it and see approach works for me. go out and have some fun . |
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Think drifting is tough. Try it on gravel, in the dark, amonst trees............... |
4 Jun 2003, 10:21 (Ref:620271) | #5 | ||
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Thanks Coln72 - it is an asphalt skidpad so I will play with the pressures a bit.
After I try to remember how to dodge the pylons!! |
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"He's still a young guy and I always think, slightly morbidly, the last thing you learn is how to die and at the end of the day everybody learns every single day." - The Ever-Cheerfull Ron Dennis on Lewis Hamilton. |
4 Jun 2003, 20:26 (Ref:621039) | #6 | ||
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I run 35 psi front, 33 psi rear on my Honda Integra Type R for most events. In fact, I run that on the road as well quite a bit. The wheels are 15 X 7 and the tires are Bridgestone SO-3 Pole Position in 205/50 VR-15. With a slightly larger profile I'd start with the 35 psi front with 33 psi rear [depending how much "rear steer" the car gives].
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"This is the law: The purpose of fighting is to win. There is no possible victory in defense. The sword is more important than the shield and skill is more important than either. The final weapon is the brain. All else is supplemental." ~ John Steinbeck |
4 Jun 2003, 22:03 (Ref:621177) | #7 | ||
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Chui: Now we are getting down to cases. It is a very smooth surface so I am not so much worried about bump steer as I am the tendency for the back end to lose grip. On the street the limit seems high but that may not translate to the autocross course.
Would much rather have an Integra Type R for this, or even better: a GS R! Cheers |
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"He's still a young guy and I always think, slightly morbidly, the last thing you learn is how to die and at the end of the day everybody learns every single day." - The Ever-Cheerfull Ron Dennis on Lewis Hamilton. |
5 Jun 2003, 06:13 (Ref:621432) | #8 | ||
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Nah, go for a RWD. Weld the diff solid and have fun sideways
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Think drifting is tough. Try it on gravel, in the dark, amonst trees............... |
5 Jun 2003, 20:04 (Ref:622182) | #9 | ||
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I have a friend who has the same car as you and I'll inquire as to the tire pressures he uses. I recall him saying ~35 psi front, ~33 psi rear. I'm not sure what other modifications he has, but he uses it daily so it's very near stock. I think he has different anti-roll bars and perhaps strut braces.
The Celica GT is a wonderful autocross car, too. Better torque curve than the GT-S and more nimble than a stock GS-R. The GT-S is a bit of a let-down when compared from that perspective. |
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__________________
"This is the law: The purpose of fighting is to win. There is no possible victory in defense. The sword is more important than the shield and skill is more important than either. The final weapon is the brain. All else is supplemental." ~ John Steinbeck |
6 Jun 2003, 09:29 (Ref:622678) | #10 | ||
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My car is completely stock and yesterday it seemed that 40 psi front and 35 psi rear worked. There was a pivot at the end of the course where it understeered horribly. I couldn't get the rear to rotate at all, but that may have had more to do with the driver than the car!
Mine was the most "stock" car there and my times weren't too bad though. I had heard good things about the Toyota. Maybe if I save my pennies... |
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"He's still a young guy and I always think, slightly morbidly, the last thing you learn is how to die and at the end of the day everybody learns every single day." - The Ever-Cheerfull Ron Dennis on Lewis Hamilton. |
9 Jun 2003, 06:39 (Ref:625301) | #11 | ||
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The other option is to buy a cheaper car and modify it as I have done. Then the car is not as restricted as it would be by driving it everyday and if oyu have a big one then it is not the end of the world, you havent lost your daily driver.
PS. it is a Toyota as well. Havent been able to kill it yet |
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Think drifting is tough. Try it on gravel, in the dark, amonst trees............... |
9 Jun 2003, 11:12 (Ref:625562) | #12 | ||
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That is actually a practical idea as well - if you need to take your daily driver to the shop you don't have to beg, rent or borrow a car.
You are right about the Toyota. You really have to abuse them (forget to put in oil, etc) in order to kill them off. A used Celica GT would make a nice platform - even an older Corolla as well. |
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"He's still a young guy and I always think, slightly morbidly, the last thing you learn is how to die and at the end of the day everybody learns every single day." - The Ever-Cheerfull Ron Dennis on Lewis Hamilton. |
10 Jun 2003, 02:08 (Ref:626655) | #13 | ||
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Yeah, mine is an early 70's Corolla. Not being registered has allowed me a whole lot of freedoms. The only down side is having to own a trailer.
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Think drifting is tough. Try it on gravel, in the dark, amonst trees............... |
10 Jun 2003, 12:27 (Ref:627017) | #14 | ||
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That would be a nice platform to start with. The car was very light to begin with, so any engine mods would show immediate benefits. Same with the suspension. With all the parts out there it would be difficult to mess it up!
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__________________
"He's still a young guy and I always think, slightly morbidly, the last thing you learn is how to die and at the end of the day everybody learns every single day." - The Ever-Cheerfull Ron Dennis on Lewis Hamilton. |
16 Jun 2003, 00:49 (Ref:632461) | #15 | ||
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Any little bit of weight I can get rid of also helps with so little power (1500cc of neck snapping grunt ) and thats bigger than the standard motor.
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Think drifting is tough. Try it on gravel, in the dark, amonst trees............... |
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