[Aro51]

Okay, so I went autocrossing Sunday and It was a complete disaster. I mean I never lost control of my car as I did that day. So here's the story..... Saturday the night before I am getting my car all setup. I put on my Victoracers and set my tire pressures. I set my pressures at 36 in the front and 34 in the back. When I auto-x I like to have more oversteer to bring the but around the turn. I wake up the next morning and head for the track. When I arrive I let my tires cool down and I checked my pressure, my front went down to 34 and my rear went down to 32, I pumped more air into them and I set the pressure back to 36 in the front and 34 in the rear. Now, I know pressures and can drop over night but when I went out and did my first run I spun out twice.... when I came back in I told my self to settle down out there. I went out for the second time taking it easy until the last turn my back came around and Spun out. I went into the pits and checked my tire pressure they were at 40 PSI ... I said HOLY S**T no wonder why my car was sliding like it was on ice. So I dropped my pressures and I finally got a clean run in.



But the ultimate question is what is the best PSI to set your 968 at?

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[bob blackwell]

With the "R Rated" tires (140 or less treadwear rating) you do not need nearly as much air pressure as you do in your street tires. The sidewalls are much stiffer. Not sure about the Kumho Victoracer but my Hoosier A6 only needed about 28 or 30 psi (cold reading) to be at their best. After running a couple of laps the pressure got up to operating pressure and worked very good. Good luck, Bob Blackwell.

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[flash]

there is no "one size fits all" pressure setting - among other things, it depends on the course, the track, the weather, the balance of the car, and your driving



unless you are a professional race driver, the best way to tell, short of comparing lap by lap, which has too many variables to really tell, is to read the tire temps



if you don't have a tire temp guage, you can "chalk" the tires and keep letting air out until you see that you use the entire tread pattern of the tire, but fall short of the sidewall, by watching the chalk wear off (if you still have chalk on the tread, you can let more air out - if you wear it off on the sidewall, put more air in)

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[kwikt]

[quote name='Aro51' post='43502' date='Nov 12 2007, 02:41 PM']Okay, so I went autocrossing Sunday and It was a complete disaster. I mean I never lost control of my car as I did that day. So here's the story..... Saturday the night before I am getting my car all setup. I put on my Victoracers and set my tire pressures. I set my pressures at 36 in the front and 34 in the back. When I auto-x I like to have more oversteer to bring the but around the turn. I wake up the next morning and head for the track. When I arrive I let my tires cool down and I checked my pressure, my front went down to 34 and my rear went down to 32, I pumped more air into them and I set the pressure back to 36 in the front and 34 in the rear. Now, I know pressures and can drop over night but when I went out and did my first run I spun out twice.... when I came back in I told my self to settle down out there. I went out for the second time taking it easy until the last turn my back came around and Spun out. I went into the pits and checked my tire pressure they were at 40 PSI ... I said HOLY S**T no wonder why my car was sliding like it was on ice. So I dropped my pressures and I finally got a clean run in.



But the ultimate question is what is the best PSI to set your 968 at?[/quote]



Where were the state championships held at? Wasn't in south Florida yesterday by chance was it.



Kevin

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[968crazy]

when I was on victoracers I ran between 32 and 34 hot temps. also after alot of testing the car worked best with the same tire pressure front and rear.

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[flash]

since i have changed the weight bias, i get different results



so far, i have to run 1.5lbs more in the front than the rear cold and with a half tank



mine is affected by the amount of fuel too - a full tank gets a bit more than a pound more air in the rear than a 1/4 tank



lol - not sure where it is going to be after this next suspension change

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[Aro51]

[quote name='kwikt' post='43512' date='Nov 12 2007, 04:28 PM']Where were the state championships held at? Wasn't in south Florida yesterday by chance was it.



Kevin[/quote]



The state championships were at moroso in palm beach on the go cart track... it was a good time. Are you from the Palm beach Area?





Hmmm I guess you gotta play with your pressures... to see what works out the best. PCA is having a autocross this sunday the 13 I will try the pressures at 32 and 34.



Alex

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[flash]

seriously - buy a tire temp guage if you can - if not, chalk the tires and watch the wear patterns

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[bob blackwell]

Not many of us use chalk (or shoe polish) anymore. You can see the wear pattern just fine by examining the scuffing on the tire after a run. Keep trying and you will find what works best for you. Flash is certainly right about all the variables involved and what feels good to me will not necessarily feel good to you. Enjoy and good luck, Bob Blackwell.

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[flash]

once the car is set up, sure - and as long as you continue to add contact patch, it's easy, but if you add pressure, and it reduces contact patch, it's a lot tougher to see



it's just easier when you are first setting it up to see the chalk wear run by run



i still prefer the temp guage though



the track day i just did, i was able to pick up over 1/2" of tread contact by using the temp guage - going by the scuff patterns alone would have left me with an imbalance left to right, as this was a clockwise track, and all the hard turns were right handers - there were enough left handers to scuff the tires evenly, but the left tire needed less air than the right because it got hotter

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[kwikt]

[quote name='Aro51' post='43538' date='Nov 13 2007, 10:44 AM']The state championships were at moroso in palm beach on the go cart track... it was a good time. Are you from the Palm beach Area?

Hmmm I guess you gotta play with your pressures... to see what works out the best. PCA is having a autocross this sunday the 13 I will try the pressures at 32 and 34.



Alex[/quote]



I here the course was fun with only 1 slolom. How did you like Richard B's RSR..... very fast!I thought about taking the DS BMW330 but decided it was toooo far. I see Danny S. took BS honors in his 944S2. Hopefully next year it'll be in Gainsville and will be competing with the 92 968. BTW I'm still looking for a set of 17x7.5 and 17x9's to mount my Hoosier A6's left over from the BMW.

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[Aro51]

[quote name='kwikt' post='43553' date='Nov 13 2007, 05:33 PM']I here the course was fun with only 1 slolom. How did you like Richard B's RSR..... very fast!I thought about taking the DS BMW330 but decided it was toooo far. I see Danny S. took BS honors in his 944S2. Hopefully next year it'll be in Gainsville and will be competing with the 92 968. BTW I'm still looking for a set of 17x7.5 and 17x9's to mount my Hoosier A6's left over from the BMW.[/quote]



Danny Shields is an amazing driver. He has his 944 s2 set up really nice. I pretty sure he has the mo30's I cant wait to get mine. *wishing* but im glad to see a Porsche take the win that day in B stock. Those 350z's give us a run for our money lol. But the course was really fun to drive maybe next State Champion ships I will see you there.



I will get some pics of my complete disaster.....



Alex

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[Aro51]

my beautiful disaster

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[kwikt]

Wow!!!!!!!!!! Did you change your shocks yet? What about swaybar? Alignment???



Kevin

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[Aro51]

not a thing done not a thing...

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[kwikt]

I'm going with a set of Koni's and possibly a 30mm front sway and of course some 17" A6's if I find a set of rims <img src="/forum/images/smilies/968/biggrin.gif" class="smilie" alt="" /> <img src="/forum/images/smilies/968/biggrin.gif" class="smilie" alt="" /> <img src="/forum/images/smilies/968/biggrin.gif" class="smilie" alt="" /> Then we'llsee how she handles.

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[bob blackwell]

You will be very satisfied with the improved handling. Be sure and change the rear anti-sway bar at the same time as you change the front - otherwise it will understeer very bad. Good luck, Bob Blackwell.

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