autocross pressure - Zilvia.net Forums | Nissan 240SX (Silvia) and Z (Fairlady) Car Forum

sliEighty · 04-15-2006, 07:02 PM

i need to know some universal tire pressures for autocross conditions...

DJPimpFlex · 04-15-2006, 08:25 PM

that is the stupidest thing I've heard in a while. To decide what PSI you need isnt just a number that anyone can give you. It depends on what tires you are using and how the tires react with certin PSI levels. An easy way to see how much sidewall deflection and roll over you are getting is to get some white shoe polish and put it on parts of your tires sidewalls. Drive hard and see where the polish wares off. If it wares off to much on the sidewall you need more pressure. If it doesnt ware on the side wall at all take the pressure down a bit. You want it somewhat to use the sholder of the tire, but not the whore sidewall. This is assuming that you are running street tires, but judging by the question I dont think I have a problem assuming that. For auto x its a bit different. You want to focus more on lateral transition rather than lateral grip because the corners are so small and close together. You should run slightly higher PSI than you would for a HPDE or something like that.

sliEighty · 04-16-2006, 05:34 PM

if you wanna talk shit get a decent car first... i dont do autocross... sorry for not knowing something, like you since you dont know that your car is fuckin gay as all types of shit.... fuck off

KwKouki · 04-16-2006, 05:52 PM

wow homeboy chill the fuck out. a million factors determine tire pressure.

What kind of car are you running, HP, susp, tires used, ect

sncs14 · 04-16-2006, 05:54 PM

Quote:

Originally Posted by sliEighty

if you wanna talk shit get a decent car first... i dont do autocross... sorry for not knowing something, like you since you dont know that your car is fuckin gay as all types of shit.... fuck off

I very much doubt that anyone here will share your point of view. Try not to bash someone(and their car) that gave you good advice. Oh, and btw he's right, it was a stupid question.

KwKouki · 04-16-2006, 06:10 PM

http://www.tirerack.com/features/solo2/handbook.htm

Read it.

NIK90s13 · 04-16-2006, 06:16 PM

Ouch!!!! You guys keep it up and this thread will be locked!! I hear it coming!!! LOL!!! Try not to take it so personal. It is good advice though.

DJPimpFlex · 04-16-2006, 06:16 PM

my car sucks?!? WTF are you talking about. I kinda like my car. Your in the wrong place to be bashing a S13.

theicecreamdan · 04-17-2006, 10:42 AM

I run like 80psi in my truck tires, it works really good for me.

BTW thread starter, Chill out, its the internet.

sliEighty · 04-17-2006, 08:50 PM

yo first of all i have an s13 too... second that wasnt me that sent that reply... so mybad for that... i just wanted an average of what people run so i could get close to what i needed...

SpeedMonkeyInc · 04-17-2006, 09:16 PM

Multiple personalities WTF!?

What tires do you have? A good starting point is to look at the max psi on the side wall then put the pressure to about 10psi less. After that, you will need to be using the shoe polish/chalk on the sidewall trick. Or a laser thermometer if you want to go high tech.
Every tire brand/type will be different.

sliEighty · 05-01-2006, 10:58 AM

hey im really sorry about that post... it was one of my friends who has the most riced out car on earth(car is made of bondo)... i do have an s13 and i love them all even if they arent the best looking... i know it was a stupid question to ask but i didnt know... thanks for the info tho... that really wasnt me tho. your advice helped me out i ran 9 sec behind a guy with a vette with over 850hp... thanks sorry for my friend

93 240sxfastback · 05-01-2006, 03:57 PM

Don't forget that your psi goes up between runs. Just play around with it until you find what you like.

g6civcx · 05-01-2006, 09:17 PM

The general rule of thumb is adding 5 PSI to the factory recommended cold pressure (measured with tyres at ambient temperature) for general performance. For track use you can experiment with +10 and up to the tyre's max pressure.

Just make sure you don't exceed the tyre's max pressure printed on the sidewall.

stinky_180 · 05-02-2006, 02:08 AM

check your tire pressure after each run. as the tires heat up the air also heats up and expands causing higher pressure. be sure to let some pressure out if it exceeds the maximum for that tire. play around with your tire pressure after each run and see what you feel is best.

04-15-2006, 07:02 PM	#1
sliEighty Zilvia Junkie Join Date: Jan 2006 Location: Central pensyltucky Posts: 471 Trader Rating: (3) Feedback Score: 3 reviews	autocross pressure i need to know some universal tire pressures for autocross conditions...

04-15-2006, 08:25 PM	#2
DJPimpFlex Post Whore! Join Date: Jan 2004 Location: Rohnert Park, CA Age: 39 Posts: 6,158 Trader Rating: (115) Rides Gallery: DJPimpFlex Feedback Score: 115 reviews	that is the stupidest thing I've heard in a while. To decide what PSI you need isnt just a number that anyone can give you. It depends on what tires you are using and how the tires react with certin PSI levels. An easy way to see how much sidewall deflection and roll over you are getting is to get some white shoe polish and put it on parts of your tires sidewalls. Drive hard and see where the polish wares off. If it wares off to much on the sidewall you need more pressure. If it doesnt ware on the side wall at all take the pressure down a bit. You want it somewhat to use the sholder of the tire, but not the whore sidewall. This is assuming that you are running street tires, but judging by the question I dont think I have a problem assuming that. For auto x its a bit different. You want to focus more on lateral transition rather than lateral grip because the corners are so small and close together. You should run slightly higher PSI than you would for a HPDE or something like that. __________________

04-16-2006, 05:52 PM	#4
KwKouki Nissanaholic! Join Date: Apr 2003 Location: Key West, FL Age: 44 Posts: 2,212 Trader Rating: (6) Feedback Score: 6 reviews	wow homeboy chill the fuck out. a million factors determine tire pressure. What kind of car are you running, HP, susp, tires used, ect __________________

04-16-2006, 06:10 PM	#6
KwKouki Nissanaholic! Join Date: Apr 2003 Location: Key West, FL Age: 44 Posts: 2,212 Trader Rating: (6) Feedback Score: 6 reviews	http://www.tirerack.com/features/solo2/handbook.htm Read it. __________________

04-16-2006, 06:16 PM	#8
DJPimpFlex Post Whore! Join Date: Jan 2004 Location: Rohnert Park, CA Age: 39 Posts: 6,158 Trader Rating: (115) Rides Gallery: DJPimpFlex Feedback Score: 115 reviews	my car sucks?!? WTF are you talking about. I kinda like my car. Your in the wrong place to be bashing a S13. __________________

04-16-2006, 05:34 PM	#3
sliEighty Zilvia Junkie Join Date: Jan 2006 Location: Central pensyltucky Posts: 471 Trader Rating: (3) Feedback Score: 3 reviews	if you wanna talk shit get a decent car first... i dont do autocross... sorry for not knowing something, like you since you dont know that your car is fuckin gay as all types of shit.... fuck off

04-16-2006, 06:16 PM	#7
NIK90s13 Zilvia Junkie Join Date: Jan 2006 Location: texas Age: 58 Posts: 471 Trader Rating: (0) Feedback Score: 0 reviews	Ouch!!!! You guys keep it up and this thread will be locked!! I hear it coming!!! LOL!!! Try not to take it so personal. It is good advice though.

04-17-2006, 08:50 PM	#10
sliEighty Zilvia Junkie Join Date: Jan 2006 Location: Central pensyltucky Posts: 471 Trader Rating: (3) Feedback Score: 3 reviews	yo first of all i have an s13 too... second that wasnt me that sent that reply... so mybad for that... i just wanted an average of what people run so i could get close to what i needed...

04-17-2006, 09:16 PM	#11
SpeedMonkeyInc Zilvia FREAK! Join Date: Apr 2003 Location: Oakland Age: 45 Posts: 1,271 Trader Rating: (0) Feedback Score: 0 reviews	Multiple personalities WTF!? What tires do you have? A good starting point is to look at the max psi on the side wall then put the pressure to about 10psi less. After that, you will need to be using the shoe polish/chalk on the sidewall trick. Or a laser thermometer if you want to go high tech. Every tire brand/type will be different.

05-01-2006, 10:58 AM	#12
sliEighty Zilvia Junkie Join Date: Jan 2006 Location: Central pensyltucky Posts: 471 Trader Rating: (3) Feedback Score: 3 reviews	hey im really sorry about that post... it was one of my friends who has the most riced out car on earth(car is made of bondo)... i do have an s13 and i love them all even if they arent the best looking... i know it was a stupid question to ask but i didnt know... thanks for the info tho... that really wasnt me tho. your advice helped me out i ran 9 sec behind a guy with a vette with over 850hp... thanks sorry for my friend

05-01-2006, 03:57 PM	#13
93 240sxfastback Leaky Injector Join Date: Dec 2003 Location: CA Posts: 55 Trader Rating: (0) Feedback Score: 0 reviews	Don't forget that your psi goes up between runs. Just play around with it until you find what you like.

05-01-2006, 09:17 PM	#14
g6civcx Post Whore! Join Date: Apr 2004 Location: Virginia, USA Posts: 5,764 Trader Rating: (5) Feedback Score: 5 reviews	The general rule of thumb is adding 5 PSI to the factory recommended cold pressure (measured with tyres at ambient temperature) for general performance. For track use you can experiment with +10 and up to the tyre's max pressure. Just make sure you don't exceed the tyre's max pressure printed on the sidewall.

05-02-2006, 02:08 AM	#15
stinky_180 Nissanaholic! Join Date: May 2004 Location: Pale Blue Dot Age: 40 Posts: 2,064 Trader Rating: (26) Feedback Score: 26 reviews	check your tire pressure after each run. as the tires heat up the air also heats up and expands causing higher pressure. be sure to let some pressure out if it exceeds the maximum for that tire. play around with your tire pressure after each run and see what you feel is best.