Square 255 or 245 with 8.5" 261s

[1forI]

For the time being, I'm going to be running square 261 oem wheels (8.5" all around) with RS3 tires.

I am FBO with Pure Stage 1 turbo and meth so I was going to squeeze as much tire as I can that makes sense.

My question is, will the slight bulge of the 255s hurt performance on the track or would 245s perform better? Or is the difference negligible?

Would love to hear from anyone who's "been there, done that" but any insight would be much appreciated since I haven't ordered the tires yet.

Thanks!

[Kgolf31]

With RS3s go 245s. RS3s typically don't like being overstuffed on a wheel because of the soft sidewall

[bmw0bsession]

Originally Posted by Kgolf31

With RS3s go 245s. RS3s typically don't like being overstuffed on a wheel because of the soft sidewall

I am happier now because they are slightly cheaper lol

[1forI]

Originally Posted by Kgolf31

With RS3s go 245s. RS3s typically don't like being overstuffed on a wheel because of the soft sidewall

Thanks! I know you've advised on tire options before, but for this particular setup is there any 255s that would yield better results with a stiffer sidewall or do you think 245 is just the best way to go with 8.5" wheels on the track?

A guy I track with is considering the same setup but has much more power than me. Should we be considering something like an RE-11 255 or is the size difference negligible?

[02rsxpilot]

Dunlop ZIIs have the stiffest sidewall in the category, as far as I know. 10mm difference is pretty negligible in real life, but then you have to factor in that the actual difference may be more or less than 10mm depending on the brands you are considering due to inconsistent tire measurement standards.

I think dcaron9999 is running 255 ZIIs squared if I remember right. He could probably chime in with his experience.

[Kgolf31]

Originally Posted by 1forI

Thanks! I know you've advised on tire options before, but for this particular setup is there any 255s that would yield better results with a stiffer sidewall or do you think 245 is just the best way to go with 8.5" wheels on the track?

A guy I track with is considering the same setup but has much more power than me. Should we be considering something like an RE-11 255 or is the size difference negligible?

If you want the best street tire on the market now, save up and get Bridgestone RE-71Rs. Beware, tires still on backorder

(I have an order placed for 255/40/17 on 9" wheels early April and still waiting). They (being Tirerack) is suppose to stock up soon.

I'd either recommend 255 sizes in a RE-71R or a ZII Star Spec. Those are really the only hard sidewall tires that I'd feel comfortable stuffing on a smaller wheel.

EDIT: You can see the type of deflection you get.

This is a 245 RS3 on a 8.5" Wheel. Look at the driver side rear tire:



and how the tire normally should look



See the differences?

[1forI]

See the differences?[/QUOTE]


Wow, yeah I see that. That's pretty significant. Point well made. I'll stick with 245s but will consider the RE-71R or Star Spec.

[Kgolf31]

Originally Posted by 1forI

See the differences?

Wow, yeah I see that. That's pretty significant. Point well made. I'll stick with 245s but will consider the RE-71R or Star Spec.[/QUOTE]
You can stuff the RE71R or a ZII on wheels.

Personally, my preference of tires based on other people reviews and my limited experience.

Best to "worst" even worst is an amazing tire

Re-71R
Rival S
RS3v2
ZII Star Spec

[Kgolf31]

I should also not the RE-71R and the ZII Star Spec will drastically help increase steering response.


The RS3 will feel spongy, so to speak on turn in, but offers more lateral grip than the ZII

Even though I've never driven on Rivals, the offer similar feeling to a RS3

Tests have shown the RE-71R is about 0.4-0.6 seconds faster on a 30 second test course than the RS3

[1forI]

[QUOTE=Kgolf31;17787685]

The RS3 will feel spongy, so to speak on turn in, but offers more lateral grip than the ZII


That's anteresting trade off to consider.

I hear the RS3 v3 is coming out between now and end of May but I can't find any info on it. Anyone heard anything about what they are changing/improving?

[Ginger_Extract]

I'm running 255/35 RS3 V2 on the OEM 261's on the rear axle, no complaints on my end. Also ran 255/40 on a 17x8.5, but the rollover on the front axle, even with -3* camber and a lot of roll stiffness, led to poor tire shoulder wear.

[dcaron9999]

Originally Posted by 02rsxpilot

Dunlop ZIIs have the stiffest sidewall in the category, as far as I know. 10mm difference is pretty negligible in real life, but then you have to factor in that the actual difference may be more or less than 10mm depending on the brands you are considering due to inconsistent tire measurement standards.

I think dcaron9999 is running 255 ZIIs squared if I remember right. He could probably chime in with his experience.

Yes. Im running the old 255/35R18 ZII's both in the front and in the back on stock style 261 rear wheels (18x8.5 ET52). They are the wear bars and still offer good grip on dry pavement.

The tires do not seem pinched at all, and sidewalls are quite firm. In fact, I immediately noticed the faster response and turn in when I moved from my RE-11's to these.

My fresh Dunlop Direzza ZII Star Specs 255/35/R18's should come in tormorrow, will be installed on same RIMS. New suspension (Swift Spec-R springs, Bilstein B8 dampers, Dinan RSM's, and M3 rear guide rods are also getting done as I type this, finally.

Quick pic of front driver side wear, 2 months ago. They are worse now ... ;-)

[Kgolf31]

Originally Posted by 1forI

Wow, yeah I see that. That's pretty significant. Point well made. I'll stick with 245s but will consider the RE-71R or Star Spec.

It's normal, you can just see how a tire will act under load.

If you throw a bigger tire with a soft sidewall, you can develop tire squirm. This can reduce turn-in and actual overall grip sometimes.

This is tire loading with 245 ZII

[135TX]

So im curious there's no mention of MPSS here?

And Kgolf31 I know some tires heat up quicker than others. What is best for road course vs AutoX? I drive road courses and need something that will hold up for 30 min sessions at speed, not overheat or get greasy...

I want lower consumable cost of 17" tires w/ more options, squared for rotation..

I am looking at DTW LT5 17x9 +41 Square set ( 5mm spacer up front, camber -2.2 F -1.5 R), likely 245 but perhaps a 255 if on a stiffer sidewalled tire.

[Ginger_Extract]

Originally Posted by 135TX

So im curious there's no mention of MPSS here?

And Kgolf31 I know some tires heat up quicker than others. What is best for road course vs AutoX? I drive road courses and need something that will hold up for 30 min sessions at speed, not overheat or get greasy...

I want lower consumable cost of 17" tires w/ more options, squared for rotation..

I am looking at DTW LT5 17x9 +41 Square set ( 5mm spacer up front, camber -2.2 F -1.5 R), likely 245 but perhaps a 255 if on a stiffer sidewalled tire.

MPSS, great on the street, shit at the track. Especially on a McStrut car, they'll fall apart.

Any of the current hot street tires will be fine on track, RS3, ZII, AD08R, etc. I will say that if you go to the track and look at what people are actually using for street tires, it's gonna be the RS3, AD08R.

[135TX]

Originally Posted by Ginger_Extract

MPSS, great on the street, shit at the track. Especially on a McStrut car, they'll fall apart.

Any of the current hot street tires will be fine on track, RS3, ZII, AD08R, etc. I will say that if you go to the track and look at what people are actually using for street tires, it's gonna be the RS3, AD08R.

Thanks Jake, I've been grinding down the shoulders on the front. I thought it was just my driving, LOL.

[Ginger_Extract]

Originally Posted by 135TX

Thanks Jake, I've been grinding down the shoulders on the front. I thought it was just my driving, LOL.

A friend of mine delaminated his MPSS after one AutoX, and one D.E. on his Audi. That vehicle has the same McStrut setup, same tire size and weight as my 1'er. He never learned his lesson and wonders why he buys tires 4-5x/year despite my insistence on a better tire.

It happens to pretty much anything that's not super light, or has struts/lack of camber, etc. Other cars can make them work okay, but they REALLY aren't track tires.

[Kgolf31]

Originally Posted by 135TX

So im curious there's no mention of MPSS here?

And Kgolf31 I know some tires heat up quicker than others. What is best for road course vs AutoX? I drive road courses and need something that will hold up for 30 min sessions at speed, not overheat or get greasy...

I want lower consumable cost of 17" tires w/ more options, squared for rotation..

I am looking at DTW LT5 17x9 +41 Square set ( 5mm spacer up front, camber -2.2 F -1.5 R), likely 245 but perhaps a 255 if on a stiffer sidewalled tire.

If you can find some RS3v1 still floating around somewhere, pick those up in a heartbeat.

The RS3v2 heat up much quicker than the v1 versions but on the flip side they grease over much quicker. I never had to spray v1 tires, on the v2 tires after 2-3 runs in 70F+ I had to spray to keep them cool.

ZIIs will overheat even faster than the RS3v2s



The new RE-71Rs have been pretty impressive so far. People have had the tire temps at 130+ and keep on throwing down faster times. However no one really have put them on a track yet. I'd kind of wait for that, they are a high wear tire (people are projecting 100-120 runs on an autocross course and they're history).

The AD08Rs are pretty impressive as well, I may actually lean this way. Driven on them with a different car, not mine. But I was impressed.

[1forI]

[QUOTE=Kgolf31;17789252]

This is tire loading with 245 ZII


Just when I thought I was set on RS3 I realized that they don't make a 245/35/18. I think that a 245/40/18 could create a fitment issue given the added height.

I know you're on 17's but any idea if this fit is possible?

I'm starting to hate tires, when I should be loving them! I wish I had an endless resource for test fitting and road testing.

[135TX]

Last track day my fronts got up to 150-160 on the outside and 140 on the inside. Rears ten degrees cooler. I'm thinking AD08R seems like a solid option.

[Ginger_Extract]

[QUOTE=1forI;17790479]

Originally Posted by Kgolf31

This is tire loading with 245 ZII


Just when I thought I was set on RS3 I realized that they don't make a 245/35/18. I think that a 245/40/18 could create a fitment issue given the added height.

I know you're on 17's but any idea if this fit is possible?

I'm starting to hate tires, when I should be loving them! I wish I had an endless resource for test fitting and road testing.

Just buy the 255/35. You'll be fine. Promise.

[1forI]

[QUOTE=Ginger_Extract]

Originally Posted by 1forI

Just buy the 255/35. You'll be fine. Promise.

Even tho you experienced poor shoulder wear with 255 up front due to the width and soft side wall on the rs3?

I don't mind if they have a slightly shorter shelf life, I just want to make sure I'm not compromising performance.