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Tire conundrum

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Well ow that you guys helped me sort out my brake problem now it's time to turn to tires. I'm a year into HPDE and love it. In that time in started with the factory all season tires, then ran MPSS, and finally ended with R888s.

The all season of course were terrible. The MPSS were awesome until I started pushing hard and the weather got hot. With the driving I was doing at that time it felt like they never even wore. Of course I wanted more so I got some 18x10 from Blowfish and ran Tokyo R888s. Now I've only had three days on them but I really like them. The do slide a little when hot but to my style very predicable and can really control oversteer with the throttle.

Here's where I'm stuck. These tires after three days look like this.89590cd1e96c354ad96e34b6757fb181.jpg

As you can see the midline tread is almost to the wear bar. These are 295/30/18s. Ideally I'd like a little taller tire because I run out of gear too often. Either way I'm not sure how much like they have and I'm starting to wonder if I should just start buying up take off slicks. It seems like it would be a better way to go.

What has your progression been? What would you advise? Keep the R compounds or go to take off slicks?

Thanks

Jake
 

Fabman

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jpt3 said:
Well ow that you guys helped me sort out my brake problem now it's time to turn to tires. I'm a year into HPDE and love it. In that time in started with the factory all season tires, then ran MPSS, and finally ended with R888s.

The all season of course were terrible. The MPSS were awesome until I started pushing hard and the weather got hot. With the driving I was doing at that time it felt like they never even wore. Of course I wanted more so I got some 18x10 from Blowfish and ran Tokyo R888s. Now I've only had three days on them but I really like them. The do slide a little when hot but to my style very predicable and can really control oversteer with the throttle.

Here's where I'm stuck. These tires after three days look like this.89590cd1e96c354ad96e34b6757fb181.jpg
Re: Tire conundrum

As you can see the midline tread is almost to the wear bar. These are 295/30/18s. Ideally I'd like a little taller tire because I run out of gear too often. Either way I'm not sure how much like they have and I'm starting to wonder if I should just start buying up take off slicks. It seems like it would be a better way to go.

What has your progression been? What would you advise? Keep the R compounds or go to take off slicks?

Thanks

Jake
I would be thrilled if my tires looked that good after 3 track days...but that's me. (R7's)
If you're burning the center out of your tires you may be running too much pressure in them.
 

302 Hi Pro

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Yes, have to agree with Fabman, a bit over inflated. Have you been recording your tire temps? Start logging cold tire pressures and then take hot temps when you come off and go from there.

Looks like your having fun with your HPDE sessions.
Good Luck,
302 Hi Pro
 
Over inflated tires wear quicker in the middle AND get greasy when hot. Try lowering your air pressure. Are you driving your car to and from the track?
 
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Thanks for the thought. To answer a few questions. I am not driving with these tires to the track. The wear is track use only!

I have not recorded temperatures but have been looking at hot and cold pressures. When I researched these tires I found several threads where people said these tires actually like higher pressures and with too LOW of pressure will wear the centers more. The reason listed was that when the tire pressure is too low the tire distorts ore under load leading to uneven wear. What I was doing was adjusting pressure based on the feel and where the wear was on the outer edge. Meaning on these there's a little triangle on the sidewall and you're supposed to have the wear line at the alex or the triangle.

What I found was that I felt the tire gripped more and wore right along the edge of the triangle with higher hot pressures of 38-40. So what do you guys think? Was this bad info?


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steveespo

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I'm sorry but R888s on a Mustang are best run at 0 psi hot, as in, not on your wheels. Seriously I found they performed best at 36 hot, but are never really fast. I had a set for 3 years that wore just like yours no matter where the pressure was. Do yourself a favor and try some Pirelli DH 305/660 or 680-18 take off slicks for about $150 ea shipped. Run 26 cold, 30 hot and you will see good durability (25 cycles even as scrubs) and great lap time. New R7s are also great but very pricey. The Toyos just suck. Steve


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Tire conundrum

voodoo child21 said:
I'm sorry but R888s on a Mustang are best run at 0 psi hot, as in, not on your wheels. Seriously I found they performed best at 36 hot, but are never really fast. I had a set for 3 years that wore just like yours no matter where the pressure was. Do yourself a favor and try some Pirelli DH 305/660 or 680-18 take off slicks for about $150 ea shipped. Run 26 cold, 30 hot and you will see good durability (25 cycles even as scrubs) and great lap time. New R7s are also great but very pricey. The Toyos just suck. Steve


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Thanks Steve this is exactly the info I'm looking for. Would love to hear other people's thoughts on r compound vs take off slicks.


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Mad Hatter

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I am very jealous that you guys can buy used take off slicks. Can only import new tires to Chile so very screwed. If I went with street tires for track competition I would get the RE 71R bridgestones. Can swap them from side to side and if they are anything like the Dirreza DZ2 then the have a lot of promise. I use my street PSS's as my rain tires or on practice laps, great tire but not that fast as some others and can overheat quite quickly. Great in the rain.
 
Worn in center is sure sign of too much air when fully heated. Many go by pressure but I noticed when working pro races many teams are also checking temp's with I/R readers. Started seeing this on Viper teams long ago. The air pressure is adjusted to get temp's as even as possiable at inside, center , & outside.

You can get the basic I/R reader for about $35. Good for checking brake temps too.
 

Fabman

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I can't tell much from the OP pic unless it's zoomed out more. The triangles on the sidewalls indicate where the wear bars are located (so CHP can find them), and have nothing to do with rollover wear toward the sidewall of the tire. I run Nitto NT01 275/40-18 on 18x10 wheels and the fitment is perfect.

If you want to check tire temps, use a probe and check immediately when off track (it's a scramble).
 

Grant 302

basic and well known psychic
jpt3 said:
Is the IR accurate enough or do you need a probe?

Probes are certainly better, but I'm using an IR gun. In cold or cool weather, the surface of the tire will vary more from the tread block temp depending on cool down lap and time in the pits anyway. But it's still a better indicator than having no data at all. It still indicates temp deltas between the inner/center/outer tread of the tire. Pretty sure an IR gun would tell you how much hotter the center was on those R888s.

And like noted above, I also use it to take and log rotor and other temps too.
 
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tetstang said:
I can't tell much from the OP pic unless it's zoomed out more. The triangles on the sidewalls indicate where the wear bars are located (so CHP can find them), and have nothing to do with rollover wear toward the sidewall of the tire. I run Nitto NT01 275/40-18 on 18x10 wheels and the fitment is perfect.

If you want to check tire temps, use a probe and check immediately when off track (it's a scramble).

Very interesting I guess I was told incorrectly about the triangles. Here's another shot.b3676fddb2bd9903d7b2fc88eb259680.jpg
 

Grant 302

basic and well known psychic
jpt3 said:
Very interesting I guess I was told incorrectly about the triangles. Here's another shot.b3676fddb2bd9903d7b2fc88eb259680.jpg

Eesh. Looks like the front right is showing too much pressure and too little static camber. Looks like the inner shouder showing ZERO wear. Might be a good idea to flip your fronts or rotate if you're running square.

What's the full suspension setup and rim/tire sizes?
 
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Grant 302 said:
Eesh. Looks like the front right is showing too much pressure and too little static camber. Looks like the inner shouder showing ZERO wear. Might be a good idea to flip your fronts or rotate if you're running square.

What's the full suspension setup and rim/tire sizes?

I'm running Koni sports with steeda sport springs and -2.0 degrees of camber. I was wondering if I should swap them.

The wheels are 18x10 and the tires are 295/30/18.

Can you elaborate on the term static camber.

Thanks for all the insights. It's very helpful!!!


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Fabman

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https://www.youtube.com/watch?v=d0voTx7AuZQ

Static camber is how much camber you have at ride height.
Camber gain (or loss) is how much camber change you have when the suspension moves.
If you have -2* static camber but when your suspension compresses 1" you have -2.5* and when it compresses 2" you have -3* camber it is said that you have .5* of negative camber gain per inch.
 
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Ok that makes sense. Do you guys fell -2.0 is enough for our cars? The car is driven 5000-7000 miles a year including track.


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Grant 302

basic and well known psychic
jpt3 said:
Ok that makes sense. Do you guys fell -2.0 is enough for our cars? The car is driven 5000-7000 miles a year including track.

Settings are often driver/track/setup specific. For example, I run less camber at Laguna Seca than I do at Streets of Willow.

Just based on the way your tires look, you could probably use more static camber. And that's probably the simplest solution. There are different ways to increase your camber gain, but most of them involve hardware changes. Increasing or maximizing caster could help if you have plates and room for the adjustment.
 

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