What are your track/AutoX alignment settings?

[HISSMAN]

-2.5 F camber
-2.25 Rear Camber
0 toe F & R

19x10 F -275/35
19x11.5 R -305/35

Steeda UL Linear Springs W/ PP Struts (Need a better strut)

Nitto NT05

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[Stuntman]

It's kind of pointless to list your alignment without disclosing what tire you're running, tire size, wheel size/width/offset, spring rates, ride height, aero mods, swaybars, % use on street vs track etc..

Suspensions work as a SYSTEM, and 1 alignment will not necessarily be ideal for an identical car with only 1 aspect of the above that's different.

Update: After a few track days and a lot of autocross, I learned that with the front suspension design (double ball-joint) the car has enough caster. Might check for build variations, but generally it has plenty. As a result, camber gain is pretty good as well so we don't need to run as much static camber.

In my case, I moved down from -2.5 to -2.1. I also went from .25" total toe in, to .25" total toe out and then came down to 1/16" total toe out. At this setting turn in is still pretty crisp without the straight-line instability. I've kept the rear at -2.0 camber and .25" total toe in. Back stays planted at this setting. Just need more tire under the front end. This is my street setting too; DD commute 83 miles round trip with about 55/45 highway/street.

Tire wear is amazing with these MPSS tires and the grip is beyond belief for a 300TW tire. Breakaway is progressive and they tell you when they are about to lose it. But I have to run 28 cold and deflate if they approach 34 - between these two seems to be the sweet spot.

Treadwear ratings are arbitrary numbers.

 

[Norm Peterson]

Treadwear ratings are arbitrary numbers.

Actually, there is a specific procedure for determining treadwear numbers. But once the mfr has tested and determined his own estimate of treadwear, his only obligation after that is that he cannot assign a higher treadwear number than what that corresponds to. But he can assign a lower TW-number (i.e. 140 for a tire that can actually qualify for 200), and this has been done particularly with respect to tires used in years past for the Street Touring autocross category.

I don't normally reference Wikipedia articles, but this one seems to be pretty well vetted.

https://en.wikipedia.org/wiki/Uniform_Tire_Quality_Grading#Treadwear


Norm

 

[Stuntman]

Actually, there is a specific procedure for determining treadwear numbers. But once the mfr has tested and determined his own estimate of treadwear, his only obligation after that is that he cannot assign a higher treadwear number than what that corresponds to. But he can assign a lower TW-number (i.e. 140 for a tire that can actually qualify for 200), and this has been done particularly with respect to tires used in years past for the Street Touring autocross category.

I don't normally reference Wikipedia articles, but this one seems to be pretty well vetted.

https://en.wikipedia.org/wiki/Uniform_Tire_Quality_Grading#Treadwear


Norm

Actually they can, because there is so much "fudge" room in the pointless test procedures they use. Manufactured can pretty much put any treadwear they want on a tire. Give this a read to better understand why:

http://www.motoiq.com/MagazineArtic...LY-select-and-size-TIRES-for-PERFORMANCE.aspx

 

[Norm Peterson]

I'm not going to critique in detail an article that seems to have an agenda (bashing the UTQG system), discounts the value of speed ratings out of hand, and doesn't understand either the Load Index system or the concept of unit tire loading not being a constant well enough to discuss them. And that's just what I noticed from a very quick scan through the pages where all I wanted to find was the stuff he wrote about UTQG.

But it would have made little sense to include HPDE-level driving as part of the test procedure intended to help the average tire consumer who if he goes to a race track at all it's to watch other people compete.


Norm

 

[Stuntman]

As long as you agree that all of the "fudge room" is on the low side of the test results.

I'm not going to critique in detail an article that seems to have an agenda with respect to the UTQG system, discounts the value of speed ratings, and doesn't understand either the Load Index system or the concept of unit tire loading not being a constant well enough to discuss them. And that's just what I noticed from a very quick scan through the pages where all I wanted to find was the stuff he wrote about UTQG.


Norm

Try giving this a read:

https://www.tirerack.com/tires/tiretech/techpage.jsp?techid=48

"UTQG Treadwear Grades are based on actual road use in which the test tire is run in a vehicle convoy along with standardized Course Monitoring Tires. The vehicle repeatedly runs a prescribed 400-mile test loop in West Texas for a total of 7,200 miles. The vehicle can have its alignment set, air pressure checked and tires rotated every 800 miles. The test tire's and the Monitoring Tire's wear are measured during and at the conclusion of the test. The tire manufacturers then assign a Treadwear Grade based on the observed wear rates. The Course Monitoring Tire is assigned a grade and the test tire receives a grade indicating its relative treadwear. A grade of 100 would indicate that the tire tread would last as long as the test tire, 200 would indicate the tread would last twice as long, 300 would indicate three times as long, etc.

The problem with UTQG Treadwear Grades is that they are open to some interpretation on the part of the tire manufacturer because they are assigned after the tire has only experienced a little treadwear as it runs the 7,200 miles. This means that the tire manufacturers need to extrapolate their raw wear data when they are assigning Treadwear Grades, and that their grades can to some extent reflect how conservative or optimistic their marketing department is. Typically, comparing the Treadwear Grades of tire lines within a single brand is somewhat helpful, while attempting to compare the grades between different brands is not as helpful."



What's the "agenda" for the UTQG system other than pointing out how flawed and I quote "USELESS" it is to draw any type of qualitative measure of a tire?

A far better tire test would be a machine that puts a certain amount of scrub/yaw into a tire and have it roll for tens of thousands of miles to simulate real world tire wear, then standardize the results into categories or wear ratings. If you read the article, you'll realize how easy it is to fudge the current UTQG test procedure to list the tire at whatever you want it to be.

 

[Norm Peterson]

All I'm going to add is that limited usefulness when you have some idea why it's limited is NOT the same thing as useless. "Useless" is an absolute and tires is a topic where nothing about them is 'cut and dry'.

Chances are you missed the delayed edit in post #80.


Norm

 

[Eritas]

Time attack and autocross competitions regulate classes by UTQG. It seems like there is a "tire war" with Hankook, BFG, Bridgestone, and Toyo changing their UTQG ratings to stay in certain classes to sell more tires.

Seems like there's no standardization or "point" for it.

 

[Stuntman]

All I'm going to add is that limited usefulness when you have some idea why it's limited is NOT the same thing as useless. "Useless" is an absolute and tires is a topic where nothing about them is 'cut and dry'.

Chances are you missed the delayed edit in post #80.


Norm

If you look at a brand and Tire A has a higher UTQG than their own Tire B, yet has more grip and wears out the same or even has better wear, then Yes, the premise of it as any sort of measuring tool is indeed useless.

Now try comparing UTQGs from one brand to another and it's even more difficult, impossible to draw any sort of valid comparison. Again, it is useless.

There are always exceptions in the case of UTQG, more often than not. If you think it's a valid tool and Brand X's higher UTQG has less grip and lasts longer than Brand Y's rating, you're behind the ball at the track.

 

[Norm Peterson]

If you look at a brand and Tire A has a higher UTQG than their own Tire B, yet has more grip and wears out the same or even has better wear, then Yes, the premise of it as any sort of measuring tool is indeed useless.

Specific example, please. And let's not be trying to compare tires that are in different categories either.


You're still trying to think in absolute terms, when the best you're going to get is a rough idea. But a rough idea is still better than no idea whatsoever. Then again, I guess it would be useless if you can't sort out a rough idea from what you're trying to call an absolute number :shrug:

I guess you have to apply a little "engineering judgment" here . . .


Norm

 

[Eritas]

Specific example, please. And let's not be trying to compare tires that are in different categories either.


You're still trying to think in absolute terms, when the best you're going to get is a rough idea. But a rough idea is still better than no idea whatsoever. Then again, I guess it would be useless if you can't sort out a rough idea from what you're trying to call an absolute number :shrug:

I guess you have to apply a little "engineering judgment" here . . .


Norm

If UTQG is a good universal measure, then what does the "category" have to do with anything? Some time attack events (and I'm sure AutoX) dictate the "categories" where a certain tire is allowed in "street" or "r-comp" with one group, while the other group bans it because it's a "cheater tire". :shrug:

I remember this comparison of the PS4S vs P-Zero (PZ4) and the Continental Extreme Contact Sport:

https://www.tirerack.com/tires/tests/testDisplay.jsp?ttid=223

"The Michelin Pilot Sport 4S presented a remarkable package... The Continental ExtremeContact Sport was a small but noticeable step behind in average lap times... Pirelli's P Zero (PZ4) had less outright grip than the Continental or the Michelin...As a result, average laps times for the P Zero (PZ4) were only six hundredths of a second behind the Continental."

Conti Sport - 330TW
PS4S - 300TW
Pirelli PZ4 - 220TW

The Pirelli has the lowest treadwear UTQG, so that should mean it wears out the fastest and has the most grip, but it's the slowest in tirerack's test. So how is UTQG helpful in any way?

 

[Stuntman]

If UTQG is a good universal measure, then what does the "category" have to do with anything? Some time attack events (and I'm sure AutoX) dictate the "categories" where a certain tire is allowed in "street" or "r-comp" with one group, while the other group bans it because it's a "cheater tire". :shrug:

I remember this comparison of the PS4S vs P-Zero (PZ4) and the Continental Extreme Contact Sport:

https://www.tirerack.com/tires/tests/testDisplay.jsp?ttid=223

"The Michelin Pilot Sport 4S presented a remarkable package... The Continental ExtremeContact Sport was a small but noticeable step behind in average lap times... Pirelli's P Zero (PZ4) had less outright grip than the Continental or the Michelin...As a result, average laps times for the P Zero (PZ4) were only six hundredths of a second behind the Continental."

Conti Sport - 330TW
PS4S - 300TW
Pirelli PZ4 - 220TW

The Pirelli has the lowest treadwear UTQG, so that should mean it wears out the fastest and has the most grip, but it's the slowest in tirerack's test. So how is UTQG helpful in any way?

Actually the 245/40-18 used in that test was rated at 300TW:

https://www.tirerack.com/tires/tires.jsp?tireMake=Pirelli&tireModel=P+Zero+(PZ4)

Either way, that PZ4 still had a lower treadwear than the ECS while being slower (virtually the same), and has the same treadwear as the PS4S but quite a bit slower.

It is interesting to go through the PZ4's tire list and see the significant variance in tread wear for their bespoke and standard off the shelf tires which range from 220-320 treadwear. Meanwhile Michelin uses "300TW" for the entire PSS & PS4S lines. Going back to the MotoIQ & TireRack articles, the manufacturer can pretty much put whatever rating on the tire they want (thus justifying the statement that UTQG is useless). Unless you believe that PSS & PS4S all have the same grip and treadwear for both off the shelf and their bespoke tire variants.

In addition:

I've had Cup2's, R888's, Nt01's, and Hoosier R7's on my 350R, and the only tire that has produced a better lap time than the factory Cup2's is the Hoosiers. Ford did a fantastic job picking/developing the right tire for the 350R. The Nt01's, and R888's are just as sticky, probably even slightly more grip, but just don't have the front end feel of the cup2's, and can be kind of numb at the limit.

Cup 2 is rated at 180 treadwear, while the R888 & NT01 are rated at 100 treadwear. Hoosier R7 is 40.

Going purely off of UTQG, the R888 & NT01 should wear out almost twice as fast as the Cup 2 and be quite a bit faster, but that wasn't the case:

The Hoosiers will cord the fronts after about 2 events (4 days), or about 20, 20 minute sessions. All the other tires mentioned including the Cup2's are more like 25+ sessions before cording the fronts.

SVTDSM said the R888 & NT01 were slower than the Cup 2 despite being 'just as sticky, probably even slightly more grip' than the Cup 2 and they all lasted about the same in terms of wear.

=UTQG is useless.

 

[Eritas]

Thanks for the info. I didn't look to see the TW was different for different sizes.

 

[qtrracer]

It's kind of pointless to list your alignment without disclosing what tire you're running, tire size, wheel size/width/offset, spring rates, ride height, aero mods, swaybars, % use on street vs track etc..

Suspensions work as a SYSTEM, and 1 alignment will not necessarily be ideal for an identical car with only 1 aspect of the above that's different.


Treadwear ratings are arbitrary numbers.

I thought I mentioned MPSS on stock rims above that post. In any event, also stock sta-bars and KWv3 at stock height (F 5/8; R 5/10). Does this make any difference for the analysis? Since mine is a DD like the majority on here, most guys are running something similar. The differences are marginal if measurable at all.

While I agree there is some question of the utility of the UTQG system, the same can be said of many standard measures. Bring on something better. Do you think your solution will pass without question or critique? Until then, we have what we have. These are not absolutes and never were. These are tools - perhaps poor ones - but just tools.

 

[Norm Peterson]

"The Michelin Pilot Sport 4S presented a remarkable package... The Continental ExtremeContact Sport was a small but noticeable step behind in average lap times... Pirelli's P Zero (PZ4) had less outright grip than the Continental or the Michelin...As a result, average laps times for the P Zero (PZ4) were only six hundredths of a second behind the Continental."

Conti Sport - 330TW
PS4S - 300TW
Pirelli PZ4 - 220TW

The Pirelli has the lowest treadwear UTQG, so that should mean it wears out the fastest and has the most grip, but it's the slowest in tirerack's test. So how is UTQG helpful in any way?

The disconnect here is the assumption that lower treadwear numbers always correspond to higher levels of grip. Reality . . . this is a piss-poor assumption to make, and this much of the problem is on the individual consumer making extrapolations that cannot be guaranteed by either the test data itself or the mfrs' willingness to divulge any more than he has to.

Yes, the mfrs sometimes do play marketing games with people who make that assumption, knowing that only a few will think any further than that number molded into the tire sidewall and referenced in the advertising. That part is on them.

Remember that tire mfrs can always "de-rate" the treadwear number down below where it actually tested. What they can't do is up-rate the number above what the test data can support. You don't think that Pirelli hopes performance drivers see their 220 tire as being grippier than those others?

It would take an entirely different test protocol to establish a correlation between grip and treadwear in a track day environment. And perhaps an amendment to 49 CFR 575.104 to get it included on the tire sidewall. Which might not be a bad idea for the relatively few of us who actually beat up sets of street tires on the track, but that's a separate matter.


Norm

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