2013 is in the books!

[dewittpayne]

The 0.975 factor didn't come out of thin air. For example, my Mustang could run STX on 265 maximum section width 140TW tires or ESP on whatever width Hoosiers, usually at least 315, with about the same allowances for suspension mods. The PAX for ESP this year is 0.849. The PAX for STX is 0.827. 0.827/0.849 = 0.974. And the Mustang isn't competitive in STX but is closer in ESP, so for it, Hoosiers probably make a bigger difference than a factor of 0.975. Arguably it will be much worse next year when it's in STU even though you can run 285 section width tires in STU. STU has a PAX almost exactly equal to ESP. Somehow I don't think that the additional 20mm wider section width will add as much performance as a set of much wider Hoosiers.

I suspect that if you compare the PAX's between cars in other ST and SP classes, you'll get about the same difference.

[steverife]

That's apples to cumquats or something...

[dewittpayne]

That's apples to cumquats or something...

Really? So what, besides wheels and tires that makes much difference can you do in ESP that you can't do in STX?

Do you think that if Mark had been driving my car instead of Jeff's that he wouldn't have given Shawn a run for his money? He was certainly nearly that much faster than I when he did drive it in September. Do you think that my car wouldn't have been at least 2 seconds faster on Hoosiers? Or more to the point, do you think that JY's car wouldn't have been at least 2 seconds slower on street tires than on Hoosiers?

Either PAX crudely equalizes performance or it doesn't. Right now, it doesn't for Stock class cars on street tires. Look at the Nationals results for RTR and compare to the same model cars on Hoosiers. That's an apples to kumquats thing too.

[steverife]

I'm not really sure what your point is, but you can't really take a single car and use to justify (or disprove) PAX for different classes/categories.

ESP PAX has been set by a heavily developed 3rd generation Firebird and a best of breed WRX.
STX PAX has been set by the FRS/RX8/E36. A Mustang has never been a real factor.
STU PAX has been set by the STi/Evo. A Mustang won't be a factor.

If you are arguing that race tires are faster than street tires, well yeah...

[MARKP]

There's a lot of difference between ST and SP. To name a few, wheel and tire width, intake and exhaust mods, weight mods, and suspension mods. I don't agree that Hoosiers are worth 2 sec against equivalent ST tires on a typical Pellissippi course.

[John Brown]

There's a lot of difference between ST and SP. To name a few, wheel and tire width, intake and exhaust mods, weight mods, and suspension mods. I don't agree that Hoosiers are worth 2 sec against equivalent ST tires on a typical Pellissippi course.

...so, your saying with any available street tire you could have gotten on the Mustang Sunday... you could have came within 2.0 seconds of your time with the HooHooz??(minus the cones)

ummmmm... Im doubrful. but Iv wanted all year to throw a set of good 275/35/15 on my car and see how close to CSP times I can get.

[ke0ki2k]

There's a lot of difference between ST and SP. To name a few, wheel and tire width, intake and exhaust mods, weight mods, and suspension mods. I don't agree that Hoosiers are worth 2 sec against equivalent ST tires on a typical Pellissippi course.

...so, your saying with any available street tire you could have gotten on the Mustang Sunday... you could have came within 2.0 seconds of your time with the HooHooz??(minus the cones)

ummmmm... Im doubrful. but Iv wanted all year to throw a set of good 275/35/15 on my car and see how close to CSP times I can get.

I'm sure if they made RS3's in 335 he could Marc has been saying the same thing about his car - 'til he remembers how much they cost.

[steverife]

You guys should split them, and let me borrow two!

I just need some junk 205's for the rear.

[TennTechMan]

There's a lot of difference between ST and SP. To name a few, wheel and tire width, intake and exhaust mods, weight mods, and suspension mods.

Add aero to that list. All the fastest SP cars have it.

[thrdeye]

The .975 multiplier gives Jed about 1.3. I'm not sure the Hoosiers are that much help.

All this talk about the .975 multiplier really doesn't mean anything. IMO, "Street" is so screwball that we don't know what the multipliers will be. There are class changes, wheel diameter changes, tire changes, 140 treadwear for one year, etc. To say you can take what we have for 2013 and figure .975 on it is nuts.

You guys kill me. There's no way Hoosiers aren't worth at least 1.5 sec on a 63 second course.

Just like any other number that is assigned to a class, it's not always going to be accurate because so much changes from run to run or event to event. But, my point has always been that .975 is in the right neighborhood and many other regions seem to agree.

Anyway, with the season over, it's a pointless discussion.

[John Brown]

The .975 multiplier gives Jed about 1.3. I'm not sure the Hoosiers are that much help.

All this talk about the .975 multiplier really doesn't mean anything. IMO, "Street" is so screwball that we don't know what the multipliers will be. There are class changes, wheel diameter changes, tire changes, 140 treadwear for one year, etc. To say you can take what we have for 2013 and figure .975 on it is nuts.

You guys kill me. There's no way Hoosiers aren't worth at least 1.5 sec on a 63 second course.

Just like any other number that is assigned to a class, it's not always going to be accurate because so much changes from run to run or event to event. But, my point has always been that .975 is in the right neighborhood and many other regions seem to agree.

Anyway, with the season over, it's a pointless discussion.

LOL! I agree with ya Chris! Like them HP guys sayin street tires wouldn't slow em down 2 seconds..
that's funny.

[scottgib]

Only a little relevant -- a number of years ago after an event on Victor Racers I changed to a good set of Azenis. On a 40 second course the difference was 1.5 seconds. Since then both the streets and R's have gotten more sticky. I could only guess if the ratio changed. On the Mini S, Hoosiers seem faster than 1.5 sec dif. vs Stones, although the wheels and tire widths were also different. I still think .975 is fairly close.

[integra55]

if I understand correctly … the .975 only matters for next yr ? after that it becomes Street and everyone is on 200 TW tires ???

[thrdeye]

It shouldn't matter even for next year. I would say there will be a rick ruth pax for the street car classes, just like with any other class now. I would be surprised if the numbers aren't close to base pax*.975 though.

[steverife]

PAX isn't a perfect science. It will be a far less perfect science next year, and probably for the next couple of years.