S197 Autox Build Thread Profile - S197 Mustangs

[SMGDHG]

I was going to try the Nankang's but apparently Nankang has a problem with customs, shipping containers are being sent back to the manufacturer. I choose to buy another set of Falken's. I am bumping up to 315/30-18s.
Quote from Phil's Tires:
UPDATE: There is an ongoing situation with all incoming containers of Nankang AR-1 and CR-S v2. This affects ALL dealers in the US. Containers have been turned away and are being sent back to Nankang by request of the NHTSA while the situation is being resolved. It is unclear when they will be sent back to the US. Nankang is doing everything possible to address the issue.
We are extremely frustrated by this and all we can do is wait. Thank you for understanding.
We have sufficient inventory in many sizes of Nankang AR-1, CR-S v2, and CR-S v1. We are doing our best to update our inventory on the website on a daily basis.

Wow, I feel very fortunate then; I ordered mine from Tire Rack maybe 4 months ago? Were at my door in 2 days. Have been a fantastic tire.

 

[Proto]

Wow, I feel very fortunate then; I ordered mine from Tire Rack maybe 4 months ago? Were at my door in 2 days. Have been a fantastic tire.

I was planning to go Re71rs this year. Trying to be more competitive at the Cam Challenge in STL this year. I was the last car that made the shootout last year. But that was only on RT660s that had a whole season of Autocross on them. I did look at the nankangs because of the larger sizes for 19x11s.

 

[SMGDHG]

I was planning to go Re71rs this year. Trying to be more competitive at the Cam Challenge in STL this year. I was the last car that made the shootout last year. But that was only on RT660s that had a whole season of Autocross on them. I did look at the nankangs because of the larger sizes for 19x11s.

Having ran both RE-71RS and the CR-S, I would buy the CR-S over the RE-71RS no question. The CR-S has been faster for me, and is wearing better.

When it came time to replaced my RE-71RS, I decided to go with the CR-S after reading this article: https://grassrootsmotorsports.com/articles/why-is-nankang-is-going-all-in-on-the-sportnex-crs/

My experience has been similar to that of the article; faster, and much better wear. The CR-S is a more expensive upfront cost, but if it does wear 30% slower than the RE-71RS, it ends up being cheaper.

Asterisk here is this is for a track car, so different animal than autocross.

 

[Dave_W]

Asterisk here is this is for a track car, so different animal than autocross.

Exactly. If you look at the individual lap times in the details of that GRM article, the CR-S is nearly a full second slower on its first lap than its best lap (lap 7). The RE-71RS is 0.2 sec slower on first lap from best (lap 3), and the A052 set its fastest time on the first lap. In autocross, you need a tire that has grip right-freakin'-now from cold, as the whole run is over in a minute or so. Horses for courses, as the saying goes.

 

[SMGDHG]

Exactly. If you look at the individual lap times in the details of that GRM article, the CR-S is nearly a full second slower on its first lap than its best lap (lap 7). The RE-71RS is 0.2 sec slower on first lap from best (lap 3), and the A052 set its fastest time on the first lap. In autocross, you need a tire that has grip right-freakin'-now from cold, as the whole run is over in a minute or so. Horses for courses, as the saying goes.

thats very true. However I will say…..My recollection of autocross (other than getting sunburned!) was 95-100°F days where RE71R users were constantly spraying and airing down after their runs, all the while complaining about going slower because their tires got hot and greasy. It seems reasonable to believe this would create an opportunity for a CR-S to catch up in “average” lap time for your runs. I would argue this is very valuable for someone who isn’t in the top 5% of talent/speed. But the proof is in the pudding; all the fastest people are running the AO-52 which is the heat soak king! So I digress.

I’m embarrassed to admit I was never fastest on the first run anyways, but I’ve only got about 30 autocross events under my belt so by no means an authority on the subject. I was always too nervous to be “that guy” and plow through cones on the first run, so I always warmed up to it.

 

[JDMac34]

Exactly. If you look at the individual lap times in the details of that GRM article, the CR-S is nearly a full second slower on its first lap than its best lap (lap 7). The RE-71RS is 0.2 sec slower on first lap from best (lap 3), and the A052 set its fastest time on the first lap. In autocross, you need a tire that has grip right-freakin'-now from cold, as the whole run is over in a minute or so. Horses for courses, as the saying goes.

My buddy went from RT660s to CR-Ss on his C6Z and experienced the same thing. They worked great on track and worked well on the last autocross run, but took forever to get to temp. He would spend his first few autocross runs warming the tires and have to pray for a hero run at the end.

 

[Bill Pemberton]

The question is often if a driver acquired the new CR-S or the CR-S V2 ( version 2 ) , as the I ran into some folks who got the tires only to discover they were on the original version. They do not heat up as fast as the RE71RSs or the A052s , yet the new ones seem pretty effective at autocrosses in the Summer and some who participate as a 2 driver car find them pretty solid on hot days. There is no doubt they are not as solid as the other two out of the box, but for the driver who wants to run both autocross and track it is another option. I recently got a new set of RR71RSs and my decision was based on chatting with a National Champion last September ( at the Solo Nationals ) and also riding with a friend at a track event last October. Both run Bridgestones at the track along with autocrossing and they both comment on the longevity of the RE71RSs if you drive on it for a bit. Over 60 autocross runs and two track events , and my friend drove 2.5 hours down from Sioux Falls, SD. and home again, convinced me that the tires may need a little road work prior to running. He still has tread and will run on the tires some this year before getting a new set. One has to wonder if the old idea of running a tire and putting it up for a few weeks to a month before really attacking a road course/autocross course still works with today's 200 TWR.

The National Champion praised the CRS ( V2 ) for fairly fast uptick on an autocross course in really hot weather, but he noted on a road course they were long wearing for the HPDE or Time Trial driver.

With all the Nankangs on hold it appears the choices are restricted but I would still look at the Yokes, Bridgerocks, and Falkens for dual purpose rubber , and there are quite a few more for those who are more concerned with just a set for the track - Goodyear F1 SC 3 comes to mind, along with the RS-4 Hankook.