[BoilerUP]

I've gotten six (6) sessions and three (3) sessions out of two sets of Pirelli scrubs purchased from JB Racing Tires, before cording a front.

Setup can be a factor (I was -3.0 front camber), as can pressures (25psi cold) and overdriving the fronts (did it a few times, lol)...but my experience with regards to longevity has not shown the value proposition of scrubs to be remotely worthwhile.

The grip was addicitive, though!

[NG329]

Originally Posted by USMUCL

Other than going 680 instead of 660, this is what I started running. However, the "20+ sessions" was not my experience the first go-around on the scrubs I got. I didn't cord them or anything, but after about 10 sessions, they fell off a bunch. By the halfway through Day 3, I was a good 3 seconds off my pace.

Maybe the next set will do better. I hit the track tomorrow . . .

I switched from 680 to 660 because I kept destroying my front fender liner, which eventually lead to headlight damage when I drove on the street. They both seem to perform at the same level for me.

When I’m really on pace, I can cord one of the fronts in a single day, but honestly, even if you replace that 1 front, you are still ahead $$$-wise.

The Pirellis’s take a little bit longer to come up to temp as they age, but it’s easily manageable. I start mine at 24psi and when I come in from the first session they are 38psi - 40psi. Then I lower them back down to about 31 or 32 hot and keep them there the whole day. If your grip feels like it’s going off, chances are your PSI has come up. As SOON as you come off the track you gotta bleed them down. Ever since I started doing that it’s been night and say difference. One of the local fast guys who drives a Porsche Cup Cayman gave me that tip and it’s really helped.

[NG329]

Also, want to point out that I ran -3.7 on the front when I corded the passenger inner front on a mostly RH biased track (NJMP Thunderbolt). I’ve since gone to -2.7 and can get 2 days out of the driver front outer before it cords. That’s 12 sessions plus the 5 or so that they arrive with, for a total of 17 sessions. No more inner passenger front cording.

[BoilerUP]

Originally Posted by NG329

Also, want to point out that I ran -3.7 on the front when I corded the passenger inner front on a mostly RH biased track (NJMP Thunderbolt). I’ve since gone to -2.7 and can get 2 days out of the driver front outer before it cords. That’s 12 sessions plus the 5 or so that they arrive with, for a total of 17 sessions. No more inner passenger front cording.

Interesting, I also corded my right front inner Pirelli both times with -3.0 camber on predominately clockwise tracks (Mid-O & NCM)

[NG329]

Originally Posted by BoilerUP

Interesting, I also corded my right front inner Pirelli both times with -3.0 camber on predominately clockwise tracks (Mid-O & NCM)

At Mid Ohio you’re probably loading the front on the brakes at the end of the back straight. I can see that cording after repeated abuse.

I raised my front ride height by 3mm adding some preload - approximately 2 full turns on the collar. It also raises the roll center and gives me a bit of oversteer.

[BoilerUP]

Originally Posted by NG329

At Mid Ohio you’re probably loading the front on the brakes at the end of the back straight. I can see that cording after repeated abuse.

Yeah China Beach had a way of doing that...<driver mod needed>

Six sessions out of that set, got 3 sessions at NCM out of the second set.

[USMUCL]

Originally Posted by BoilerUP

I've gotten six (6) sessions and three (3) sessions out of two sets of Pirelli scrubs purchased from JB Racing Tires, before cording a front.

Setup can be a factor (I was -3.0 front camber), as can pressures (25psi cold) and overdriving the fronts (did it a few times, lol)...but my experience with regards to longevity has not shown the value proposition of scrubs to be remotely worthwhile.

The grip was addicitive, though!

I'm at -3.6 and -2.6, and they wore evenly . . . just stupid fast, LOL. The addictive grip went away quick.

That said, I'm at $650ish per set of four, inclusive of install and taxes. If I get 3 days per set, albeit with the 3rd day slower, the fun-to-dollars calculation might continue to work.

[USMUCL]

Originally Posted by NG329

If your grip feels like it’s going off, chances are your PSI has come up. As SOON as you come off the track you gotta bleed them down. Ever since I started doing that it’s been night and say difference. One of the local fast guys who drives a Porsche Cup Cayman gave me that tip and it’s really helped.

I did adjust pressures as the day went, but I'll try your specific technique and see how it goes.

[ariZona28]

Originally Posted by daniel.drives

Been a while here, how many days have you been getting out of the RRs? I’ve been running Nexen Sport R in 305/30/19 on a square and rotatable set of apex 19x11, I get 5-6 days depending on how shit the track surface is. I also like them because they’re super consistent once they warm up, but $300ea is pretty damn cheap for tires this size

OK, I officially "overstayed my welcome" on my RR tires at 8 days (33 sessions). Last track day at AZ Motorsports Park I shifted from 3rd to 4th rather aggressively and spun the car 360 degrees at approximately 100 mph. Luckily nobody else was around and I was in the middle of a fairly long straight. I'm going to say the RR is good for maybe 20 to 25 sessions in my application. I was going to run them to the cords for Research and Development purposes but even though there is still some meat left I have declared them Heat Cycled Out. Keep in mind my C5 Z06 weighs anywhere from 500 to 1000 pounds lighter than Camaros and Caddys so use your good judgment.

[VaporPressure]

Nice, where are you getting tires for $650 including install? If they're in good condition that is a great deal.

I don't reliably get 2 full days out of scrubs either. By mid-second day I'm always off pace a few seconds. Probably by my 6-7th heat cycle. As far as tire life goes, I think driving style matters a lot. I had been cording the outer shoulders quickly, but was able to get them to last a full weekend by taking warmup laps easier and doing more of them before pushing. On the other hand, back when I would overdrive the exits, early and aggressive throttle would induce a lot of understeer, lots of corrections, and the inner shoulders would be trashed by the 2nd day (all with the same alignment). I run -3.3 front, zero toe.

One other thing that might help with tire life - on chilly mornings, the first session I'll go out on higher pressures (30-32ish) and bleed down in the pits once I hit 38 or so, then finish the session. That, along with more warmup laps on all sessions, usually allows me to get the tires to not to cord for 2 full days. But pace is definitely off by then.