Tire Talk Megathread

[leftfootbr8king]

Also a set of 295/30 RR is right around a grand for a set. That’s tough to beat. NT01 sucks in the wet, but RR is simply unusable so it depends on whether the tires will need to do any wet work or if they can be a dedicated dry track set up.

[rhyary]

Why pay more for front tires?
This version (N1) was some of the fastest front tires I tested.
Perfect for NYST.

[IamFODI]

Since we brought up the PSS5:

4:00 – Michelin's stated reason for the naming change is a new naming strategy they'll apply over their whole lineup.


5:30 – Michelin's stated reasons for why the PSS5 is currently OE-only:

1. They're in no hurry to replace the PS4S for the aftermarket because it's still kicking ass and taking names, and

2. Whenever they get around to replacing it, it'll be with with something else that's under development.


So, for now at least, it looks like the PSS5 is more of a preview of things to come than a product that'll be relevant to us in the immediate future.

[derbo]

Originally Posted by IamFODI

Since we brought up the PSS5:

4:00 – Michelin's stated reason for the naming change is a new naming strategy they'll apply over their whole lineup.


5:30 – Michelin's stated reasons for why the PSS5 is currently OE-only:

1. They're in no hurry to replace the PS4S for the aftermarket because it's still kicking ass and taking names, and

2. Whenever they get around to replacing it, it'll be with with something else that's under development.


So, for now at least, it looks like the PSS5 is more of a preview of things to come than a product that'll be relevant to us in the immediate future.

Thanks for reading into the details. I was planning to have this be my next street tire but really can't go wrong with PS4S.

[IamFODI]

Originally Posted by derbo

Thanks for reading into the details. I was planning to have this be my next street tire but really can't go wrong with PS4S.

Yeah, I have a few gripes with the PS4S that the PSS5 seems to address, so I’m a little bummed myself. But having to live with the PS4S for another couple of years or whatever sure is a 1st world problem.

[rg1220]

With all the talk about the Nitto NT01's (which my most recent HPDE instructor highly recommended who also has an e92 m3); I don't know much about the load rating of tires except that I believe stock competition wheels were 93Y XL front and 98Y XL rear. However, the Nitto tires on a 18x10" square setup is 275/35ZR18 95W (non-XL). I'm not going over 168mph on track so I'm not worried about the speed rating difference but wasn't sure about the rear weight rating difference or the XL rating. Any insight?

[Gossypiboma]

Originally Posted by rg1220

With all the talk about the Nitto NT01's (which my most recent HPDE instructor highly recommended who also has an e92 m3); I don't know much about the load rating of tires except that I believe stock competition wheels were 93Y XL front and 98Y XL rear. However, the Nitto tires on a 18x10" square setup is 275/35ZR18 95W (non-XL). I'm not going over 168mph on track so I'm not worried about the speed rating difference but wasn't sure about the rear weight rating difference or the XL rating. Any insight?

You'll be fine.

[bigjae1976]

Originally Posted by IamFODI

Yeah, I have a few gripes with the PS4S that the PSS5 seems to address, so I’m a little bummed myself. But having to live with the PS4S for another couple of years or whatever sure is a 1st world problem.

The only thing I hope the PSS5 upgrades is it won’t turn rock hard after 2 years. The PSS and PS4S wear extremely well but it’s kind of pointless because the tire loses is compliance after awhile even if garage parked.

I’m on PS4S for street only use I’ve put 15k miles on them and they tread is still at 6-7/32 and the rubber is getting to the rock hard/useless point. I hate throwing tires away with tread left…it’s a track thing🤣.

I’m probably going to go with a 200 treadwear tire and just stick them on my track car after 2 years to wear them out. At some point when I dd something else I’ll probably throw something like a cup 2 on.

Originally Posted by rg1220

With all the talk about the Nitto NT01's (which my most recent HPDE instructor highly recommended who also has an e92 m3); I don't know much about the load rating of tires except that I believe stock competition wheels were 93Y XL front and 98Y XL rear. However, the Nitto tires on a 18x10" square setup is 275/35ZR18 95W (non-XL). I'm not going over 168mph on track so I'm not worried about the speed rating difference but wasn't sure about the rear weight rating difference or the XL rating. Any insight?

IIRC, the NT01s are XL rated.

You do need XL rates tires. Otherwise they won’t last. Tires on track see higher loads (G’s) and thus have to have more weight carrying and heat dissipation capacity.

If you stick a lower load rated tire on your car and drive it on the street, it will last about half as long as a properly rated tire.

[slcook54]

Okay. So this was 2.5 days at Thunderhill. RE71RS. 295/30

Ordered two new sets. One 275/35 and one 295/30. Going to experiment with both.

[IamFODI]

Originally Posted by bigjae1976

The only thing I hope the PSS5 upgrades is it won’t turn rock hard after 2 years. The PSS and PS4S wear extremely well but it’s kind of pointless because the tire loses is compliance after awhile even if garage parked.

I’m on PS4S for street only use I’ve put 15k miles on them and they tread is still at 6-7/32 and the rubber is getting to the rock hard/useless point. I hate throwing tires away with tread left…it’s a track thing��.

Huh. Interesting. Don't think I've ever had that experience, or heard of it. Maybe I never owned them long enough. Or maybe it's a climate thing? (I'm in PA)

My main gripe is that steering response isn't as sharp as I'd like. Do you disagree? I noticed it immediately on my previous car, which came to me on Bridgestone Potenza RE050As. The PS4S is obviously the better tire overall but it tangibly blunted the car's responses. I feel like I've seen similar comments in reviews. Seems like this is one area of improvement in the PSS5, so I'm hoping the PS4S's successor does the same.

Originally Posted by bigjae1976

IIRC, the NT01s are XL rated.

Some sizes are, most aren't. The size rg1220 was talking about isn't listed as XL: https://www.nittotire.com/competitio...d-course-tire/

Originally Posted by bigjae1976

You do need XL rates tires. Otherwise they won’t last. Tires on track see higher loads (G’s) and thus have to have more weight carrying and heat dissipation capacity.

If you stick a lower load rated tire on your car and drive it on the street, it will last about half as long as a properly rated tire.

AFAIK – and someone please correct me if I'm wrong:

Weight carrying capacity is mainly defined by load index, i.e. 95/98/101 etc. XL vs. SL is load range, which is an older and more general/vague rating of a tire's overall strength. AFAICT, the main practical implications of load range are

1. Max inflation pressure, and
2. How long you can safely run near max load and inflation pressure.

...But if the main concern is how much load a tire can take, that's much more accurately shown by load index.

I can easily imagine bad effects from load index being too low. It's less clear to me how lacking XL would be a huge negative, as long as the load index was right. Though, given the choice, I agree it's better to have XL than not to have it.

The tire rg1220 mentioned has a load index of 95, which means a capacity of 1521 lbs. That's around 60% higher than an E9x M3's unsprung corner weights without significant weight reduction. Personally, I'd want more margin than that, but I can't really argue with the experiences of people who've actually tried it.

[bigjae1976]

The PS4S is not a sticky tire which may cause a muted feeling. I’m not familiar with the other tire to compare.

Load rating is weight carrying capacity. So a tire has to be stronger and also handle with more heat (probably more important). On track, cornering and braking forces load up the tires because of more weight transfer.

Normally a higher load and speed rating means a more durable tire. But with track tires, it’s kind of like UTOQ. Numbers really don’t mean a whole lot.

I ran Hankook RS3s which lasted about 3 maybe 4 days - 95W rated. An NT01 would last twice as long, same rating and less tread.

[IamFODI]

Originally Posted by bigjae1976

The PS4S is not a sticky tire which may cause a muted feeling. I’m not familiar with the other tire to compare.

AFAIK, it's not the grip; it's the structure. The PS4S grips harder in all conditions than the RE050A I had, but the structure is more compliant, so there's more of a delay in its responses. It's something like, rather than fighting the deformation of the contact patch, which would have come with an NVH penalty, Michelin focused on controlling how it deformed to maximize grip and reduce hot spots ("Variable Contact Patch").

[Bartledoo]

Originally Posted by IamFODI

AFAIK, it's not the grip; it's the structure. The PS4S grips harder in all conditions than the RE050A I had, but the structure is more compliant, so there's more of a delay in its responses. It's something like, rather than fighting the deformation of the contact patch, which would have come with an NVH penalty, Michelin focused on controlling how it deformed to maximize grip and reduce hot spots ("Variable Contact Patch").

Probably depends which version PS4S though, since Michelin likes to make infinite variations of the “same” tire lol. Want your PS4S to be faster than competitor X’s PS4S? Just show them the $$$

[IamFODI]

Originally Posted by Bartledoo

Probably depends which version PS4S though, since Michelin likes to make infinite variations of the “same” tire lol. Want your PS4S to be faster than competitor X’s PS4S? Just show them the $$$

NGL, that video and the one below made me strongly consider going for the Star Spec PSS over the PS4S. Main reason I didn't was the prospect of losing wet grip.

[Bartledoo]

Originally Posted by IamFODI

NGL, that video and the one below made me strongly consider going for the Star Spec PSS over the PS4S. Main reason I didn't was the prospect of losing wet grip.

When it comes time to replace the heavy runflat ps4s on my C8 oem wheel set, it’s going to be a tough decision between a mix of BMW, AMG, Ferrari, and generic versions of the PS4S in oem sizing…

[slcook54]

Sorry if it's a repost. Found in F80 general chit chat. Relevant for RT660 and RE71RS users

https://grassrootsmotorsports.com/ar...d-longer-life/

[Bartledoo]

Originally Posted by slcook54

Sorry if it's a repost. Found in F80 general chit chat. Relevant for RT660 and RE71RS users

https://grassrootsmotorsports.com/ar...d-longer-life/

Da link broken

[Cmassey3]

Do most summer tires get hard after 2 years? I'm tracking some 2 year old Conti ECS this month.

[spxxx]

Originally Posted by Bartledoo

Da link broken

GRM tests showed that almost all of the super-200tw tires were significantly faster (0.7-1sec faster on a 1.5min lap) once worn to ~ 4/32nd's. Less tread squirm and better contact patch were their conclusions.

It'd be awesome to see Bridgestone/Yoko stop pretending they're making street tires and make an RE71RS semi-slick, same compound with a little RR style DOT tread line - call it a 100tw or whatever they want.

It's also interesting to hear about the new 2023 compound for the Nankang CR-S, their tests showed faster laps than the RE71RS, A052, etc. Phil's tire said they arrive in port Early-May. Might take a gamble on a set.

[slcook54]

Originally Posted by Bartledoo

Da link broken

Should be good now.

[Gossypiboma]

Originally Posted by slcook54

Okay. So this was 2.5 days at Thunderhill. RE71RS. 295/30

Ordered two new sets. One 275/35 and one 295/30. Going to experiment with both.

I just finished day 4 on my first set of RE71RS' and my tires are doing the same. Front camber is -3.2 and rear is -1.9.

[slcook54]

Originally Posted by Gossypiboma

I just finished day 4 on my first set of RE71RS' and my tires are doing the same. Front camber is -3.2 and rear is -1.9.

What size? I’m happy with 4 days, not 2.5.