SCCAForums.com

Hmmm..Lets see...TypeR...2500 lbs...225-45-15 A6's=9.0" tread width on 7.5 but let's go 8.25 for smaller rim since Hoosier are cantelivered.

CobaltSS...245-35-18 710='s 9.8" tread width on 8.5 but we got 7.5 so we get under 9" width since 710's lose width quickly with smaller rims.

.75 of an inch more might be a big difference in the X rated movies but it ain't much when you weigh 400lbs more.

GS, here we come!

LOL!

FM

 

Well, if we run the Kumho like yourselves, we are stuck with a 205 section width.  Can the Cobalt fit the 285 Hoosiers?

Nope...wouldn't want to either. I feel the Kumho in the 245 section width is faster than the 285 hoho on asphalt when using 8" wide rims or less.

FM

Fastmike:

Hmmm..Lets see...TypeR...2500 lbs...225-45-15 A6's=9.0" tread width on 7.5 but let's go 8.25 for smaller rim since Hoosier are cantelivered.

CobaltSS...245-35-18 710='s 9.8" tread width on 8.5 but we got 7.5 so we get under 9" width since 710's lose width quickly with smaller rims.

.75 of an inch more might be a big difference in the X rated movies but it ain't much when you weigh 400lbs more.

GS, here we come!

LOL!

FM

 

 

 

Most of the faster Type-R's are running 275's on 6" wide wheels and weigh closer to 2400lbs. Just an FYI 

---

Nick Jackson
04 S2000 - BHP Brakes
71 240z w/some stuff

SerNick:

Most of the faster Type-R's are running 275's on 6" wide wheels and weigh closer to 2400lbs. Just an FYI

 

True?  In that case it really makes me wonder about the whole R-Compound thing even more.  

275s on a 6 wide wheel to do well...that is pretty far from stock.  

I wish stock class cars were more streetable...like stock.   I'd love to see fewer autocross classes with more street tires in the "lower" classes. 

SerNick:

Most of the faster Type-R's are running 275's on 6" wide wheels and weigh closer to 2400lbs. Just an FYI 

I don't know about that one...I have only seen one ITR on the 275's, and that was at nationals last yea. all the ones i've seen before, and since, are either on the 205 kumho's or the 225/205 staggered hoosier setup. how many different cars have you seen with the 275's?

---

Bridesmaid Racing
2008 SCCA Nationals DS Runner-Up
2008 Kansas City NT DS Runner-Up
2008 Milwaukee NT DS Runner-Up
2007 SCCA Nationals DS Runner-Up
2007 Milwaukee NT DS Runner-Up
2006 ASN Nationals DS Runner-Up

 

 

The only person I know of running the 275 is Grangier and he was slower at Nationals last year than other years when he ran the 225's. He is going to try 275/205 combo this year.  We'll see how that works.

The Type R's weighed in at Nats last year were around 2500 lbs according to that scale.  Some were down around 2475 (maybe a bit lower), ours was 2520 with AC and exhaust.

aansorge:

The only person I know of running the 275 is Grangier and he was slower at Nationals last year than other years when he ran the 225's. He is going to try 275/205 combo this year.  We'll see how that works.

Feinburg ran the 275 hoosiers at a couple national events this summer on his Type R.   

---

Chike Dellimore - Blue Ridge/Washington DC Regions
2006 Galaxy Gray 6MT Mazda RX-8 (B-stock)
Former 2006 Steel Gray 5spd WRX (D-stock)

"I have a lot to work on...crazy is still on the list."

and he just won Finger Lakes Pro on 275's, Chang also runs 275's but has been off the pace a bit

 

 

btw, if the cobalt gets moved to GS, they better stick the speed3 there as well, because on paper, the cobalt already wins the bench race between the two

---

Scott
07 Mazdaspeed 3

Chiketkd:

aansorge:

The only person I know of running the 275 is Grangier and he was slower at Nationals last year than other years when he ran the 225's. He is going to try 275/205 combo this year.  We'll see how that works.

Feinburg ran the 275 hoosiers at a couple national events this summer on his Type R.   

 

I don't want to speak for any of the guys running the 275's on the 6 inch wheels, but from what I have heard is on a sweeper intensive course they 275 seems to have more outright grip but they are much more sloppy feeling on a transition instensive course.  I am running 285's on my front 7.5 inch wide wheels and I love them.  I have run 245 Kuhmos and 245 Hoosiers prior to this.  First of all the 285 Hoosiers last as long as the 245 Kuhmos do and offer better turn in grip as well as out right grip.  Secondly I can run a wider rear tire which helps put power down better and not get the understeer issues of running the larger stagger.  I am now running 285/295.  I have tried 245/295 and 245/235 (really 255).  I really prefer the feeling of the big tire setup as you can really get after the car in slaloms and it stays under you where it didn't stay with you as much on the smaller tires.  Would the big tires work really well on asphalt when it is cold that is another question.

---

Keith
2008 Honda S2000

What is the Crossfire running profile wise with a 285... like a 285-30 or something??

That 275 that the ITRs are running ( which isn't a TON of them, only a few here and there that I've run against nationally ) are a taller profile, which is why they are sloppier in transistion heavy courses.

I might be running a 245/35 at Nationals this year instead of my 245/40s. I like the grip I have got with the sweepers, but it feels a bit more vague in the slaloms. THe only trade-off for me would be hitting the top of 2nd quicker, but I doubt it'll be a noticeble difference than my 225/40s from last season.

those ITRs look like FWD dragsters compared to the more regular sized ITR tired guys. But the results don't lie.

NO way you're fitting the 275 on either Cobalt even with a spacer...at least not by the math I did and eye-balling...

 

---

Brian Huber
06 Cobalt SS-SC (retired to DD Duty )
02 Z06 ( Whole new ball o' wax )
#??SS

Beans:

and he just won Finger Lakes Pro on 275's, Chang also runs 275's but has been off the pace a bit

 

 

btw, if the cobalt gets moved to GS, they better stick the speed3 there as well, because on paper, the cobalt already wins the bench race between the two

 

Yes... I saw the MS3 was on the list to be moved as well. Same as the SRT4s...

 

---

Brian Huber
06 Cobalt SS-SC (retired to DD Duty )
02 Z06 ( Whole new ball o' wax )
#??SS

Darkhelmet:

What is the Crossfire running profile wise with a 285... like a 285-30 or something??

That 275 that the ITRs are running ( which isn't a TON of them, only a few here and there that I've run against nationally ) are a taller profile, which is why they are sloppier in transistion heavy courses.

 

The 275/15 is the SAME height as the 225/45/15 Hoosier that everyone's been using for years.  They're sloppy because you're shoving a 275 onto a 6" wheel, and the sidewalls are at such an angle.

---

Jesse
-2002-2006 E-stock 93 MR2 (sold)
-2007-2008 XP Spyder

129STS:

Darkhelmet:

What is the Crossfire running profile wise with a 285... like a 285-30 or something??

That 275 that the ITRs are running ( which isn't a TON of them, only a few here and there that I've run against nationally ) are a taller profile, which is why they are sloppier in transistion heavy courses.

 

The 275/15 is the SAME height as the 225/45/15 Hoosier that everyone's been using for years.  They're sloppy because you're shoving a 275 onto a 6" wheel, and the sidewalls are at such an angle.

 

Oh, OK... just looks like the there's more sidewall there. Optical illusion with there being sooo much extra meat there.

---

Brian Huber
06 Cobalt SS-SC (retired to DD Duty )
02 Z06 ( Whole new ball o' wax )
#??SS

The 275/15 is the SAME height as the 225/45/15 Hoosier that everyone's been using for years.  They're sloppy because you're shoving a 275 onto a 6" wheel, and the sidewalls are at such an angle.

Right in fact if you examine the tire it appears from the mold lines that the thing is produced as a 2 inch / 50mm wider 225.  Like they inserted a ring or hoop to space the existing mold halves further apart.  They can always add another 25 or 50 or 75 mm width in this fashion, economically....350s on 15 x 6 anyone, haha?

 

Data point:

Cobalt SS faster than GS MiniS on day 1 of Packwood Tour.

Mini S faster than Cobalt SS on day 2 of Packwood Tour.

Similar conditions. Similar skilled drivers. Mini got a rerun on day 2 though.

Mini driver new to car on day 1. Cobalt driver has been in the car for a few events.(but had to use bags on day 2 due to single driver/cloudy-coolish run group)

http://www.scca.com/popup/raceresult.aspx?event=12142&file=343

 So...Does the Cobalt SS/TC fit better in GS or DS?

Cobalt weighed 2915lbs on SCCA scales. Could get that down to 2875lbs with some custom stuff and a little lower fuel.

What does the 07 MiniS weigh?

FM

 

Ok, so the new SS is a tad heavier than my 06....

I weighed in @ 2907 in Topeka last year with 1/2 tank of fuel, the spare and it's gear in there and the trunk mat. ( forgot to take it out )

I'm sure with my new running setup it would be a bit lower..

---

Brian Huber
06 Cobalt SS-SC (retired to DD Duty )
02 Z06 ( Whole new ball o' wax )
#??SS

Fastmike:

Data point:

Cobalt SS faster than GS MiniS on day 1 of Packwood Tour.

Mini S faster than Cobalt SS on day 2 of Packwood Tour.

Similar conditions. Similar skilled drivers. Mini got a rerun on day 2 though.

Mini driver new to car on day 1. Cobalt driver has been in the car for a few events.(but had to use bags on day 2 due to single driver/cloudy-coolish run group)

http://www.scca.com/popup/raceresult.aspx?event=12142&file=343

 So...Does the Cobalt SS/TC fit better in GS or DS?

Cobalt weighed 2915lbs on SCCA scales. Could get that down to 2875lbs with some custom stuff and a little lower fuel.

What does the 07 MiniS weigh?

FM

 

 

Dude, you know you want the Slobalt in HS, just admit it...

btw, what happened to straight timing BS? We almost got you on PAX and everyone knows DS has the softest PAX out there...

JK, the Cobalts looked good out there, but it would be nice if Chevy would put a little more spring under them!

 

---

In slow, out fast.
In fast, out backwards.

Fastmike:

What does the 07 MiniS weigh?

 2500'ish

---

Steve Rife
ETRSCCA

mwood:

Fastmike:

Data point:

Cobalt SS faster than GS MiniS on day 1 of Packwood Tour.

Mini S faster than Cobalt SS on day 2 of Packwood Tour.

Similar conditions. Similar skilled drivers. Mini got a rerun on day 2 though.

Mini driver new to car on day 1. Cobalt driver has been in the car for a few events.(but had to use bags on day 2 due to single driver/cloudy-coolish run group)

http://www.scca.com/popup/raceresult.aspx?event=12142&file=343

 So...Does the Cobalt SS/TC fit better in GS or DS?

Cobalt weighed 2915lbs on SCCA scales. Could get that down to 2875lbs with some custom stuff and a little lower fuel.

What does the 07 MiniS weigh?

FM

 

 

 

btw, what happened to straight timing BS? We almost got you on PAX and everyone knows DS has the softest PAX out there...

 

 

He was clearly sandbagging on day2!

---

2007 STU National Champ