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CUcelica
04-19-2006, 07:47 PM
I was wondering what anyone here runs? I have the parada spec 2's. I'm really new to autox. I ran 40 psi all around the last 3 events.

yotas4life
04-19-2006, 08:17 PM
no, drop it to about 25 psi, will help you get more grip

Hiko
04-19-2006, 09:26 PM
no, drop it to about 25 psi, will help you get more grip

But will absolutely destroy our tires. Dustin, if you want proof, check out my right rear at the next event.

I ran 37 pounds at the last two events. I had good grip and the tires lasted just fine. True, I could've reduced the pressure, but these are also DD tires, and we are not going to be competitive in STS. Just some food for thought.

yotas4life
04-19-2006, 10:25 PM
ive ran my rt-615's at 25 psi on 25+miles of mountain runs numerous times, about 3 auto x's last year and there still at 30% tread left, and theres no noticable wear on the sides

acutally on the track i run them at 17 psi and ive never had a problem, if you have crappy $60 radials and big sidewalls then yes it will ruin your tires but if you have any lesss than 50's it wont do much if anything

Toyota_Todd
04-19-2006, 10:27 PM
Take some white shoe polish and mark the sidewalls. This will let you know how much your tires are rolling over on the sidewalls. If you are wiping out all of the shoe polish, up your pressure until it quits wiping off. Good luck and have fun.

Morwan
04-20-2006, 12:54 AM
no, drop it to about 25 psi, will help you get more grip

Are you retarded? If you run that low with most tires, you'll be running on your sidewalls.

It really depends on the tires, but usually 10 psi above street is good. Using shoe polish or chalk is the best way to tell; just overinflate your tires and check the wear after the first run.

yotas4life
04-20-2006, 02:37 AM
no, im just smarter than you and dont buy thick sidewalled tires,
i run my 215-40-16's at 25 psi all day and i have NO sidewall marks, at the track i even run 17psi fore more grip and ive never had any problems

you are retarded

Morwan
04-20-2006, 03:37 AM
Read the title: 'AutoX tire pressure'. Tracking is quite different from AutoX. Running lower pressures is nice for straights, but with the lateral G's you're getting on an AutoX run, you want to run as high as you absolutely can. Any sidewall flex is a loss of traction on the corners.

If you're running a stock class, you'll be using 14" or 15" tires. The thinnest sidewall you can get on a 14" tire is 215/55/R14. 15" is also similar. The 5th gens aren't very competitive in stock, and even less so in STS.

Either way, the best PSI you're going to get from using chalk/shoe polish. Also, try checking if your tires have treadwear markings on them, they should look like little arrows.

roman
04-20-2006, 03:46 AM
no, im just smarter than you and dont buy thick sidewalled tires,
i run my 215-40-16's at 25 psi all day and i have NO sidewall marks, at the track i even run 17psi fore more grip and ive never had any problems

you are retarded

Trust me, the last thing 25psi will give you is traction when you autocross. Your tires will be rolling over on the sidewalls so bad you won't get any grip. Not to mention piss poor steering responce. I don't care how low profile they are. I have plenty of pictures of cars autocrossing, some of them with under-inflated tires. You can clearly see them rolling over even on low profile rims.

As far as pressure, different tires like different pressures. I'm not sure what the Parada Spec 2 like. They're not really a "performance" tire. I remember the old Azenis really liked to be in the high 40's (in the 14" size). They gripped well in the high 30's, then started to slip as you approached 40psi. But for some reason as you hit 45 or higher they gripped even better. Just do as Toyota Todd said; take some shoe polish or chalk and mark your tire at 3 different spots right on the corner. After your run you can see how much your tire rolls over by the chalk mark (where it erased).

Also if your sidewalls are really soft there is no amount of (safe) presure that will keep them from rolling over. I autocrossed a rental Cavalier on shitty 195/70R14 touring radials once and they rolled over about 1-2 inches even at 55psi.

yotas4life
04-20-2006, 03:58 AM
i still stand that me running at 25 psi helped me grip better than at 45 psi on my rt-215's

roman
04-20-2006, 04:06 AM
Maybe on a rough surface running on 16" or 17" wheels I can see that. But even the low profile tires I wouldn't take much below 30 on a smooth lot.

Again, you're talking about the RT215. Those things had the stiffest sidewalls out of any street tire at the time. I remember I parked my car with one wheel up on the curb. Barely. Just the edge near the sidewall was on the curb the rest was anging over thin air. The sidewall didn't even bulge.

If he runs 25 psi on Parada Spec 2's I guarantee he'll ruin his tires.

yotas4life
04-20-2006, 05:45 AM
yea, there not the greatest, but my rt-215's and rt-615's are best at 25-30 psi