[sr71bb]

Well guys and gals I have probably run over 70 track events over the last three years and I would say I have run MOST of them on either Pirelli Slicks or Michelin Slicks.

I have ALWAYS found that the issue with slicks is that you dont have alot of feedback by just looking at them at what their useful life left is. I have posted elsewhere that I determine that generally by looking at my track times to see if I am getting a fall off. While I do STILL think that is the best indicator this FALL OFF can happen pretty quickly.

A case in point is this last weekend when I was tracking with a set of tires I KNEW probably were coming to the end of their life. After I did a session, the fall off I was seeing was DRAMATIC to the tune of about 4-5 seconds off my best lap times.

I knew the slicks were typically 4-5 seconds FASTER than street tires so being curious about that I took off the slicks and put on my street setup which consist of MS 4S 300TW tires. So the bottom line is I could run almost identical times within .02 of a second with the street tires vs the slicks.

So the slicks are basically toast even though the rubber was NOT worn down past the wear indicator dots. They were simply heat cycled out. After carefully examining the slicks I could see where there was some balling up of the rubber on the inside edges. I could NOW also see the grainy area of the rubber starting to show thru on a couple of them. NONE of these visual clues were present on the tires when I FIRST started the session.

So I guess my suggestion is once you get your lap times starting to fall off (1-2 seconds) I would consider changing out tires.

[Christian1LE]

I tested new Hoosier r7 slicks vs SC3s and it was a 2.5 second difference at CMP. Still running them to see how many laps I can do, but I've seen guys run the R7s to the cord.

[sr71bb]

Originally Posted by Christian1LE

I tested new Hoosier r7 slicks vs SC3s and it was a 2.5 second difference at CMP. Still running them to see how many laps I can do, but I've seen guys run the R7s to the cord.

Have you ever compared SC3R's to R7's??? I heard that their track times are VERY similar but the R7's last MUCH longer.

[Christian1LE]

I have not. The only tires I've tried are used pirelli slicks, hoosier R7, SC3's.

The used pirelli slicks are very similar in laptimes to new hoosier R7's, the big advantage of the pirelli slicks is they are much lighter tires. About 5lbs lighter(per tire) compared to the hoosiers.

[khcoaching]

Originally Posted by sr71bb

Have you ever compared SC3R's to R7's??? I heard that their track times are VERY similar but the R7's last MUCH longer.

The Hankook Z214s I used feel and act like Hoosier R7s..maybe not quite as fast, but very close. I'm just over a second quicker with the Z214s on the SLE over the 3Rs, but but the stars have to be aligned to get the 3Rs to lap that close.

Ken

[wakespeak]

Originally Posted by sr71bb

Have you ever compared SC3R's to R7's??? I heard that their track times are VERY similar but the R7's last MUCH longer.

I get about 4 days (16 25min sessions) out of the SC3Rs. The tires drop off gradually and are about 2 seconds slower at COTA toward the end. I am looking into trying the R7s.

[sr71bb]

Originally Posted by wakespeak

I get about 4 days (16 25min sessions) out of the SC3Rs. The tires drop off gradually and are about 2 seconds slower at COTA toward the end. I am looking into trying the R7s.

m

Your SC3R's are lasting LONGER than I expected. The takeoff slicks that I run that are MICHELIN N9 compound last also around 4 track days. With the PIRELLIs (MEDIUMS) I get about SIX track days BUT they are NOT as sticky as the MICHELINS hence they produce slightly slower lap times.

Typical COLD air pressures I run are about 24 PSI. As we get HOTTER weather I will drop that to maybe 22 PSI cold. These slicks DO NOT like PSI HOT to be more than 30-32PSI. In the HOTTEST weather the difference between HOT PSI and COLD PSI can be 10-12PSI. The fronts of course usually get 2-3 pounds MORE PSI HOTTER than the rears when you compare the two.

My STREET tires Michelin 4S (300 TW) I run at 28-30 PSI cold on the rare occasions that I run them on the track. Because of my very aggressive NEGATIVE camber settings, I run them at 38-40PSI COLD for daily driving along with almost neutral TOW settings. I DO NOT change the alignment settings form track to street mode. Tire life on the Michelin 4S tires is ABOUT 15-20K miles.

Typical track session for me are scheduled for about 25 minutes EACH but I usually run them no longer than 15-20 minutes . After about 15-20 minutes the tires will warm up to the point I am losing some amount of traction as indicated by my track times which I constantly monitor with my GARMIN. My FASTEST lap times usually occur between LAP 4 and LAP 6 in each track session.

[carguy55]

After many years using the G3Rs, I ran the Z214s at a couple tracks recently and they are fast, probably as fast as an R7. I did get some take off slicks to try out when I can, but the Z214 is a great tire if you're setup to run 315/30-18s and want to try someting other than slicks.

[RUQWIKR]

The scrub slicks in the sizes typically ran on our cars come off of different race cars between the fronts and rears. I'll measure durometer, tread thickness, yet, at times, I have a lot of difference front to rear in lateral and / or longitudinal grip along with variation in how many sessions I get before a drastic fall off in performance. That said, I buy and mount two sets at a time, and I have at least two mounted "fresh" sets of scrubs if going to an out of town event with them.

Yet, despite scrubs not being a perfect thing, they are a great bang for the buck if you get some "good" sets.