13" tires for autocross/track/street

[Kitcat]

I had this discussion about ZZRs with Josh, at Rocky Mountain Caterham just now. My Caterham is undergoing a moderate spa treatment there. It includes suspension mods and new 13” wheels and ZZR tires. As to compound, they recommend A64 over A24 for trackday use.

 

Per Josh, the A24s need a different suspension set up with massive negative camber. And, as noted here, they don’t last as long. He predicted 4 track days. He also noted that all ZZRs are horrible in rain. Maybe a factor if driving them to and from the track?

 

Anyhow, all in the FWIW catagory.

[KnifeySpoony]

Appreciate the input. living in CA, rain is basically a non-issue. I don't plan on making a habit of running the A24s, but I think I will try them at some point. For now though, I've ordered a set in the A64. They should still give me some PRs over my ZZS (easy ego boost), but last a while, and not beat up the car as much.

 

[Kitcat]

Good! The upside to the drought? He confirmed they were definitely faster.

[13poisons]

As I posted in the general thread, I recently bought Stalker #53.

 

I purchased Hoosier A7 13” tires (225/255) for 13x8 front and 13x10 wheels that came with the car.

 

Hoosier recommends 3 degrees of negative front camber in their A7 literature.

 

The previous owner told me that any more than 1/2 a degree is counterproductive on a classic Stalker.

 

However, he was always running slicks.

 

Any advice?   I am attending a time trial this weekend and don’t want to ruin a new set of Hoosiers.

[Croc]

 

I use the Hoosier R7s on a Caterham and do not follow the negative camber recommendation for that tire.  I found it handled better on the standard front end set up and have stayed that way.  I have not noticed any adverse characteristics or wear by ignoring the manufacturer recommendation.    

 

While R7 is different to the A7, I think you try your new A7s with your existing set up and fine tune from there as needed.  

 

 

[Croc]

12 hours ago, Kitcat said:

Per Josh, the A24s need a different suspension set up with massive negative camber. 

 

Similar to my Hoosier R7 observation above, I find my Caterham is better on the standard set up with ZZRs without a ton of negative camber.   Avon may recommend it but you should not follow that recommendation if it does not work for you.  No adverse wear or grip issues.  

[sltous]

@KnifeySpoony How have your ZZR tires been on the roads near Alices?  I have a set of R888 tires that are just about worn out, typically street use but I've done one Sonoma day already and have another lined up in October.  I have a set of ZZS that are okay but a little harder than the R888, leaning for another set of the R888R as my local tire shop can get them. 

[KnifeySpoony]

I actually haven't really street-driven the ZZR, other than to/from track. They don't feel particularly unsafe going around corners, although they don't have much grip when cold. However, neither do ZZS actually. You can't properly heat up a ZZS on the street either, so either way grip is suboptimal. I'm running more camber with the ZZR so the outer 1/3rd of the tire isn't even on the ground with street driving, which I'm sure doesn't help front grip. 

[bball7754]

Just came across these, which are available for both 13 and 14 inch rims.

 

https://philstireservice.com/shop/nankang-ar-1/

[sltous]

On 9/6/2022 at 8:46 AM, KnifeySpoony said:

I actually haven't really street-driven the ZZR, other than to/from track. They don't feel particularly unsafe going around corners, although they don't have much grip when cold. However, neither do ZZS actually. You can't properly heat up a ZZS on the street either, so either way grip is suboptimal. I'm running more camber with the ZZR so the outer 1/3rd of the tire isn't even on the ground with street driving, which I'm sure doesn't help front grip. 

Thanks.  I think I'll stick with the R888R for this set of wheels, allegedly I'm at Sonoma in October and getting some new tires is probably a necessity before that.

[KnifeySpoony]

Which Sonoma day are you going to? I've found ZZS to be very capable on track, they don't really leave a lot to be desired TBH.

[NSXguy]

1 hour ago, sltous said:

Thanks.  I think I'll stick with the R888R for this set of wheels, allegedly I'm at Sonoma in October and getting some new tires is probably a necessity before that.

I'll be using Toyo r888rs on my new (to me) 13s as well. Will see how they perform. 

[sltous]

32 minutes ago, KnifeySpoony said:

Which Sonoma day are you going to? I've found ZZS to be very capable on track, they don't really leave a lot to be desired TBH.

October 6th through Hooked on Driving.  I went with their instructors in July and it was an awesome first track experience so I'm doing the one on one with an instructor again.  Hoping to feel ready to graduate to solo but that might have to wait for next year.  Not chasing any lap times just looking to have a good time and rev out the engine some.

 

I like the R888R as a street tire because it's quite grippy without requiring a lot of temperature, nominally the ZZS are my 'winter'/wet road tire as they have a lot more tread and the R888R are quite a bit cheaper so pending availability I think it's a good tire to stick with for track and three+ season road tire for now.

[KnifeySpoony]

I wonder if the 888 compound is different in 13" sizes, because when I ran them on my Exige, I felt they did not do well on street, as they were hard to get heat into and it was understeer city.

 

Sonoma is a pretty technical track so some expert instruction will take you far. Most people I see there are running bad lines. I love Sonoma in the 7- it's really the perfect track for a 7. Thunderhill west would be great too. I still love Laguna, but the 7 really comes a live on a flowing, technical circuit. It just transitions so much better than a big heavy car. Remind me what 7 you have?

[sltous]

S3 with a CSR 260 engine swap

[KnifeySpoony]

Ah yes, the Prisoner car. We met at Alice's.

[sltous]

Probably.  I end up there pretty often.  Shoot me a PM if you want to meet up on purpose, happy to throw you the keys

[KnifeySpoony]

I don't street drive much, I'm usually up there on a bike. I'm sure I'll be up there again at some point though, especially after this heat passes. Always fun to run around on track with another 7 as well, so hopefully we'll cross paths on track at some point. 

[sltous]

Swapped to a new set of R888R, took some pictures of the fronts (heavily worn down past the wear bars but fairly uniform) and the rears (again uniform but not as heavily worn).  I don't know if it's understeer or normal steering wheels getting worn due to usage, happy to hear any thought on setup changes others might advise based on pictures.  All pictures taken as if from the front of the car

 

I probably could have gone with new fronts and kept the rears for a bit longer but they were older date code tires and for safety I chose to replace all four.

 

[KnifeySpoony]

Those look brand new!