| Author |
Message |
Hubert Otlik (Hugh)
Member
Username: Hugh
Post Number: 284
Registered: 1-2002
| | Posted on Wednesday, November 06, 2002 - 12:46 pm: | |
Billy Bob:
Unfortunatly, no, I don't run a 348 track car, just a measly Honda; however, what I have learned on the track applies ubiquitously. I have run upwards of -3.5 degrees of camber with mild toe settings and have been able to get away with driving the car TO the track w/ out wearin the tires prematurely. Regarding the tire question. Regarding toe:
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More toe out in the front: Turnin quicker, also called Turnin oversteer, if excessive.
Car is darty: Reduce toe out in front. Toe in in the rear. If car pushes in mid corner add more toe in. Remember it is always better to err on the safe side and run too much toe in than not enough.
-nsxprime
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Regarding the v700's; they are good and inexpensive, and are more like a really, really sticky street tire than a flat out slick; although they are still an R compound tire, I'd compare them against the a032r and the ra1 and at full tread can be used in moderate rain. However, they need to be shaved if you plan to campaign them in dry conditions, as they really tend to go away if you use them from full tread. The hooisers are a full slick, and as such really, really grip, but have NO wet traction, period. Also, while the v700 are 'closer' to a street tire v. the hooiser they are a bit more communicative, in my hands, than a full slick, and will give you more warning than the hooiser, in my experience; however, my experience has been limited w/ hooisers as I'm not quite there yet; but, I will say that stepping up to r compounds is amazing, youll be shocked atthe grip, the amount of braking increase, etc. Try the v700's first, that would be my advice.
Mitch:
Your right, tire pressures are critically important, however, to truely know if your running the right temps for a given setting of camber, you need a pyrometer; some rules of thumb:
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If you want MAX performance and you are going to the track, get yourself a tire pyrometer. This is the best way to test your setup. After doing several laps you should test the tire temps at three places across the tire(outside 1/4, middle and 1/4 inside edge). Start from the side of the car that you think the tires will be hottest (usually the most loaded corner of the car). You can tell several things from the temps as follows: hot in middle = too much air pressure; hot on each edge = not enough air pressure; equal temps across tire = not enough camber; hot on outside edge of tire = not enough camber; 5-15 degrees hotter on inside = camber is good!
-nsxprime
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Mitch Alsup (Mitch_alsup)
Junior Member
Username: Mitch_alsup
Post Number: 203
Registered: 4-2002
| | Posted on Wednesday, November 06, 2002 - 12:28 pm: | |
SO2s and S03s are 51 PSI max pressure tires, while the original S01s were 44 PSI max pressure tires. Tire rack indicates that air pressures should be closer to 40 PSI than the book values of 32 rear 35 front for the S01s.
Insufficient air pressure can be a cause of rear end instability, both at high speed and under braking.
So I would like Angelo to come back with the air pressures he has been using--and that he found unstable. And I would like the group to chime in with what they know about using max performance tires with high MAX pressure capabilities.
Should we "go by the owners manual" (i.e. 32 PSI); add a certain amount of pressures (like +7 PSI ->39 PSI); or should we add a reletive amount of pressure (+32*51/44 -> 37 PSI)?
I think chasing caster, camber, and toe without getting the tires into the right range is frqught with peril. |
billy bob (Fatbillybob)
Junior Member
Username: Fatbillybob
Post Number: 67
Registered: 8-2002
| | Posted on Tuesday, November 05, 2002 - 11:45 pm: | |
Herbert are you running a 348 track car? What are your suspension settings for toe and camber front and rear. I'm working up that learning curve and can use some help. I'm also deciding between Kumho Exsta v700 or Hoosiers any comments on those? Do you have ay comments on the widest tires that have been successful on stock 348 rims?
TIA |
Hubert Otlik (Hugh)
Member
Username: Hugh
Post Number: 278
Registered: 1-2002
| | Posted on Monday, November 04, 2002 - 5:30 pm: | |
Angelo:
Camber, itself, is not soley responsible for tire wear, honestly; the toe settings are also at fault, if your car is set up w/ too aggressive toe, then you will expereince premature wear, and you may make your car skidish, especially at the rear. You should review your last 4 wheel alignment receipt to get a feel for your last settings and try a more conservative toe setting in the rear. I run ~ -2.5 -> -2.8 degrees of camber on my track car, but run conservative toe settings to limit tire wear; something close to 1.5 total toe out in the front and 1 degree total rear.
Just my two cents. |
David J. Smith (Darkhorse512)
New member
Username: Darkhorse512
Post Number: 21
Registered: 10-2002
| | Posted on Monday, November 04, 2002 - 1:14 pm: | |
Billy bob
"If you have lots of neg and you go straight the straight line performance suffers as does the wear."
Thats what I was referring to as his like most cars will probably see a fair amount of straight line driving away from the track. |
Kevin Butler (Challenge)
New member
Username: Challenge
Post Number: 19
Registered: 9-2002
| | Posted on Monday, November 04, 2002 - 8:55 am: | |
FYI...(-3.5) degrees is standard setup for Challenge cars. |
Randy (Schatten)
Member
Username: Schatten
Post Number: 442
Registered: 4-2001
| | Posted on Saturday, November 02, 2002 - 11:34 pm: | |
Angelo - are you on S02 pole positions or S03 pole positions? the S02 PP's have been discontinued and are quite a horribly handling tire, the S03 PP's on the other hand are pretty darned good, especially in the wet.
Since you are tracking the car - you should keep a log book of where you went, and what alignment settings, tire pressures, brake pads you use. Then again, it depends how much you want to get into it. It helps gauge what works, what feels too much over steer or too much understeer - and just overall helps you as a driver learn more from your car and how it behaves. |
Angelo H. Oliva (Blicima_355)
New member
Username: Blicima_355
Post Number: 14
Registered: 8-2002
| | Posted on Saturday, November 02, 2002 - 9:18 pm: | |
Hey David,
Ferrari of SF changed my camber. At the time I was tracking it at Sears Point. I have had my tires set normal and negative camber. Let me tell you, for those of you that have never driven with negative camber, your missing out... Unbelievable response and handling, but you will pay for it...
Have fun...
Angelo |
billy bob (Fatbillybob)
Junior Member
Username: Fatbillybob
Post Number: 64
Registered: 8-2002
| | Posted on Saturday, November 02, 2002 - 8:44 pm: | |
"As you know negative camber is degenerative adjustment. The more you put in the shorter your tire life. Too much negative front camber also reduces the tire contact patch, increases braking distances and makes the car more pitch sensitive on tur"
Well not really. You see if you are turning all the time and the camber is balanced for the agressiveness on the turn you have even wear. If you have lots of neg and you go straight the straight line performance suffers as does the wear. It is all a compromise. You have to find it for your drive style. The simple things to balance are tire type...try DOT legal race tire like Kumho victoracers. Try camber adjustments. Try air pressure adjustments taking out air to get more stick up to a point. Try lowering. Try tire size variation. Wider rears tends to help neutralize tail happy mid-rear weight biasis cars. |
David J. Smith (Darkhorse512)
New member
Username: Darkhorse512
Post Number: 19
Registered: 10-2002
| | Posted on Saturday, November 02, 2002 - 3:50 am: | |
Angelo,
Just curious who changed your camber?
It's important to decide what the performance objective is for your car. Will your car see alot of track time? Do you want to drive on a more leizure like regimine?
As you know negative camber is degenerative adjustment. The more you put in the shorter your tire life. Too much negative front camber also reduces the tire contact patch, increases braking distances and makes the car more pitch sensitive on turn.
A good way to check if the camber thats giving you good cornering balance is also good for your tires would be to measure tire temperatures at the outside middle and inside of the tread before and after a romp through your favorite set of corners.
Or, you could contact the nearest dealer who has had a "Challenge" program for original settings. |
Hans E. Hansen (4re_gt4)
Member
Username: 4re_gt4
Post Number: 355
Registered: 4-2002
| | Posted on Friday, November 01, 2002 - 11:25 pm: | |
Angelo: Just BE CAREFUL. If the wheels are too 'upright', the back of any independant rear suspension car gets real scary. I experimented with this on an old Corvette, trying to avoid wearing out the inside edge of the tires. The back end of the car would break loose just looking at a corner.
You may be able to modify the settings somewhat, just go somewhere safe to see how the new settings work. |
Angelo H. Oliva (Blicima_355)
New member
Username: Blicima_355
Post Number: 13
Registered: 8-2002
| | Posted on Friday, November 01, 2002 - 9:59 pm: | |
Just wanted to get some feed back on setting your back tires with negative camber. What degree can you set your tires with a negative pitch, yet not having to replace your tires every 3000 miles? My 355 has Bridgstone "Pole Positions" (Best tire I have ever driven on) I am ready for a new set however I don't remember the negative degree they are set at.
Any suggestions???
Angelo |
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