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      05-31-2023, 09:15 PM   #1
dre99gsx
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Hoosier R7 advice

Looking for any input on Z4s who've raced on Hoosier R7s - (or E46 with 3100-3200lb weight). What are your cold and hot temps for ideal longevity and grip, and how many heat cycles do you get before it drops off to where they are undriveable?

I currently run Toyo RR high about 37psi hot and really like these tires, but looking to experiment with more traction.
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      06-01-2023, 06:15 AM   #2
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Since Hankook Z214’s weren’t available at the end of 2021, I decided to try a set of A7’s and R7’s for 2022.

They seemed to like 38 psi hot and lots of camber.

The A7’s gripped more consistently to cord at around 10 hc’s. R7’s made it to about 14 hc’s and still had half the meat on the bone when they just all of a sudden had no grip. Didn’t like them for a track day tire. If you’re sprint racing maybe…

Hoosiers definitely needed a different setup than Hankooks and by the time I figured it out they were off peak so my lap times were slower than on Hankooks. Hankooks are $100 per cheaper so I’m back on Hankooks.
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      06-01-2023, 08:54 AM   #3
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Can you give me more details on Hankooks? How did you like them grip wise and longevity wise? What pressures worked for you?
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      06-02-2023, 07:19 AM   #4
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I've been racing and tracking with Hankook Z214's for about 15 years, so I do have a bias. For me, they have proven to be good value (if there is such a thing) when comparing their price, grip and wear. Hoosiers have more peak grip but fall off dramatically. Hankooks have a very flat grip curve where I've laid down some my fastest laps after 15 HC's. Depending on how much you scrub them, they will usually last to 20 HC's for me.

I can't compare to RR's as I've not run them, but a friend did a back to back at Roebling Road on his IP racecar (E36 M3) and found the RR's to be about 2 seconds slower than Hankooks on a short 1:18 lap. Admittedly, some of this gap could be due to RR's needing different camber and psi. He didn't attempt to setup the car for the RR's. As I found with my Hoosier experiment, different tires can require very different setups. Word is that the RR's wear like iron but have less grip than Hoosiers or Hankooks. So should be a good track day tire if you don't mind giving up a bit of grip.

As for setup, I run 275/40/17 square and have found the sidewalls to be very stiff. What works on my car I find odd, but it is what it is. I run low camber and low psi compared to the Hoosiers. Camber is -2.5f and -1.5r and 33psi hot. Not sure if it's a tire size thing with this particular Hankook size, as my previous car, also an IP racecar, liked -3.5f/-2.0r and 36 psi.

https://hankookmotorsports.com/produ...37854010474663
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      02-03-2024, 08:21 AM   #5
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Reviving this thread due to BMWCCA revamping PWR3 club racing rules to allow a + modifier to cars using Toyo RR. I’ve been using R7 as my race tire but only five days of racing so far. I’ll use up my current allotment at Road Atlanta in March and will need to buy more. I had good success with Hankook RS4 as an HPDE tire, so I’m open to Z214, but if I go with Toyo I can drop more weight and/or gain some HP.
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      02-04-2024, 07:32 AM   #6
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Spec tire

It would appear this rule change has effectively made PWR a spec tire series. The reasons given are nonsense.

If you make the switch to Toyo RR's, remember that you then can't run a Hoosier wet as your rain tire. It must be a >180 treadwear tire.
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