Everett Ogilvie

How do you guys rate/compare the A6 with the slick compounds R80 and R100? How about life? Thanks for any input.

Gman57

Hope to hear some discussion on this

waddisme

I bought like 12 scrub R80s for $500 back in the fall for HPDEs. I have 23 sessions on the first set so far. 1/2 of the sessions at VIR, 1/4 at Rd Atl and 1/4 at Charlotte/Daytona. Not corded yet and honestly not even looking like they need to be flipped. I don't push my car 10/10s, but the R888 scrubs I had barely got 8 sessions and I paid $200 plus for 4 of them.

Here is a typical 1 lap vid at VIR that shows about how hard I push them:



HTH

RX-Ben

What kind of air pressures do you run on R100s?

AU N EGL

My understanding is

A6s are the softest. then R6s

the R80s are softer then the R100s

The construction of the R80s and R100s are very different from the A6s and R6s

so not always apples to apples.

the Old VRLs were the same as the R6 rubber compound but a stiffer sidewall

RX-Ben

Yes, the R100s that I have (Conti Grand Am 285/645) have sharp shoulders, way different than the rounded A6/R6.

Everett Ogilvie

Thanks for posting this, looks like they work pretty well for you!

Everett Ogilvie

I wonder if the slicks are lighter weight than the A6 and R6 (for a similar size).

RacePro Engineering

Hi Tom,

I do not wish to put you on the proverbial spot, but where did this bit of MIS-information come from?

Ed

Corvee

On R100s I ran 25*cold and hot temps were 35-37* this past weekend in 50 - 60*ambient temps.

Sidney004

The Conti GrandAm 285/645 is not the same as the R100. Different internal construction(the GrandAm was designed to sustain the loading on the banking at Daytona) I am not certain as to how the compound compares to the R100.

Racingswh

From my research yes they are lighter than a comparable size A6. 325/710/19 at 27.6 lbs which is physically larger than the 325/30/19 A6 at 29 lbs.

1ED1

Race Pro

Instead of asking a question why don't you tell us what you know.

Gman57

yooper

Regarding the Conti's, what is the difference between the GT-O and the GT-R?

redtopz

I thought he just said the A6's are softer than R6's and the R80's are softer than R100's. Is that not true?

I ran a set of R80 F/R100 R before (off a porsche race car) and was impressed with the level of grip, the lack of fading off like an A6, and how long the tires lasted from a physical wear standpoint.

RacePro Engineering

Ed,

My name is Ed, just like yours!

I used to immediately post what I knew to be true. I found that, facts aside, folks would argue with me.

Not long ago, I took the time to revise and post here a pretty lengthy technical discussion on racing wheels and tires. It contains knowledge that we have gained over the years, not from theory, not from books, and certainly NOT from the world-wide-web; but from running real cars on real tracks, representing hours upon hours of testing.

Tom is usually "right-on" with his information, so somehow he has gotten something skewed, probably by someone else "speaking" authoritatively on a subject about which they know very little. I am just curious of the source.

Also, I am certain that Everett knows very well the mechanical grip ranking of all the Hoosiers in question, so there is no need for me to correct for his benefit. I believe he is more looking for first-hand experience on tire "behavior", consistancy, and wear characteristics.

For those interested, there was another thread some time ago on which I discussed the use of a durometer. That would be good to search for too.

Ed

RacePro Engineering

What you wrote is true. However, "Softest" is a superlative, not a comparative. If my understanding of grammer is getting in the way, then, Ted, I apologise.

Slicks are in a category of their own! And, if one is impressed with the current radials, especially the 80 and 100 compounds, one should try a nice set of bias-ply - maybe a 45 compound - whole other OTHER world.
Ed

travisnd

Too bad NASA has the .75 penalty for slicks. I'd like to try some

RacePro Engineering

I know you would, and you would be one who fully used the additional grip!
?? Should be .075 ??
And, in case there is any (ANY) doubt whatsoever about the inherent grip differences between a good DOT radial, and a good slick, one has only to look at this NASA "Equalization Factor" in added weight.

Thanks for reminding me, Travis.
Ed