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[Inf4life]

Originally Posted by Mr. Liu

I have two sets of front 255/35 PSS I am trying to get rid of. One set has less than 100 miles, takeoffs from my M4, BMW OEM spec.

Second set is 7/32 even wear. Can ship

How much shipped to 77407??

[OneMmmm]

Thought I would chime in and offer some help to those looking for these tires.

If you must have these and must have them now, call a MB dealership near you to see if they have them in stock. I called two dealerships in my city and both had these available - 275/35/19 (100Y).

Downside is that you will most likely pay a premium over what Tire Rack would charge. Upside is that you don't have two wait another 2+ months for Michelin to get their act together.

[YolkyPalky]

Well, I threw my hands in the air and just gave up on getting the Michelin PSS 255/275 "upgrade setup" (275 was the harder to find).

I decided I am just going back to stock OEM sizing of 245/265 in Michelin PSS, which are available. On a positive note, I'll save some money, and perhaps its not really that much of a difference, but I guess I will find out after having driven on the 255/275 set up for quite some time.

What do you guys think, will there be a noticealbe difference dropping back down to 245/265 after having 255/275 for a long time? If so, in what ways?

[CSBM5]

Originally Posted by YolkyPalky

What do you guys think, will there be a noticealbe difference dropping back down to 245/265 after having 255/275 for a long time? If so, in what ways?

Honestly, having mixed and matched wheel widths and tires sizes for over 40 years on performance cars, I'd wager that if you notice anything other than the typical new tire stuff (i.e. much better grip with new, non-heat-cycled rubber, quieter and better riding due to full tread depth) it would be slightly better transient response.

[YolkyPalky]

Originally Posted by CSBM5

Honestly, having mixed and matched wheel widths and tires sizes for over 40 years on performance cars, I'd wager that if you notice anything other than the typical new tire stuff (i.e. much better grip with new, non-heat-cycled rubber, quieter and better riding due to full tread depth) it would be slightly better transient response.

Interesting. I'm not sure I really know what transient response means as relates to tires, could you explain the term transient response a little bit?

[gimmethemuumuu]

Originally Posted by YolkyPalky

Well, I threw my hands in the air and just gave up on getting the Michelin PSS 255/275 "upgrade setup" (275 was the harder to find).

I decided I am just going back to stock OEM sizing of 245/265 in Michelin PSS, which are available. On a positive note, I'll save some money, and perhaps its not really that much of a difference, but I guess I will find out after having driven on the 255/275 set up for quite some time.

What do you guys think, will there be a noticealbe difference dropping back down to 245/265 after having 255/275 for a long time? If so, in what ways?

I've got a pair of gently used PSS 245/35-19's for sale.

PM me if you're interested

[CSBM5]

Originally Posted by YolkyPalky

Interesting. I'm not sure I really know what transient response means as relates to tires, could you explain the term transient response a little bit?

Turn-in response during the transition from straight ahead to loading up the tires fully would be one aspect of transient response. Another example would be doing a slalom on an autocross course where you are going back and forth from fully loaded cornering in each direction -- those transitions are transient.

As you increase wheel width, holding tire size constant, you increase the effective spring rate (stiffness) of the sidewall and thereby increase the transient response -- similarly, holding wheel width constant and decreasing tire size is analogous.

We're only talking about a minor change here (10mm of section width), so it's likely not noticeable to most drivers who are not using their cars in aggressive driving (autocross, HPDE) and do not have significant experience doing so.

To imagine the flip side of this discussion, consider holding the wheel width constant and now jumping up three section width sizes -- 275s up front, 295s in the rear. In the same situation, transient conditions, you would notice a "floppy" or sloppy feeling to the tires compared to the smaller section width 245s/265s.

Under essentially every driving condition on public roads and by the vast majority of owners, the differences between 245/265 and 255/275 are simply looks pretty much.

Regards,
Chuck

[YolkyPalky]

^^^^ So it sounds like you are saying that aside from the "looks" difference which some may prefer wider, going to OEM size 245/265 may in fact at the slightest of margins drive/handle better than a bigger 255/275 setup.

I always thought "more meat on the road" in the 255/275 was better, but now I can see how it may not necessarily translate into better handling or responsiveness. Is that what you were saying with the 'transient response' being better with the OEM sizing?

[CSBM5]

Originally Posted by YolkyPalky

^^^^ So it sounds like you are saying that aside from the "looks" difference which some may prefer wider, going to OEM size 245/265 may in fact at the slightest of margins drive/handle better than a bigger 255/275 setup.

I always thought "more meat on the road" in the 255/275 was better, but now I can see how it may not necessarily translate into better handling or responsiveness. Is that what you were saying with the 'transient response' being better with the OEM sizing?

Yep, transient response will be a tad better with OEM sizing; however, "handling" has a zillion different meanings. For example, for SCCA street (stock) class autocross where you are constrained to stock width wheels, I run a square tire setup, 275/35-18 all around, for balance and net grip reasons, with 8.5 front and 9.5 rear wheel widths. Even though the fronts are pinched a bit on 8.5" OEM sized front wheels (non-ZCP) and they give up some of the taught feel of an OEM sized front tire, they make up for it in peak grip and braking. Hence in this situation, 275/35-18s all around yield a good bit of gain in grip and hence quicker times on an autox course even though the fronts loose some in transient response.

Hence it's likely that on a carefully measured autocross course with an excellent driver, one could eek out a better time with 255/35-19,275/35-19, versus the OEM sizes even though there might be a small loss in transient conditions (which on course you can make up for by turning sooner and anticipating/accommodating a slightly sloppier response).

[YolkyPalky]

Originally Posted by CSBM5

Yep, transient response will be a tad better with OEM sizing; however, "handling" has a zillion different meanings. For example, for SCCA street (stock) class autocross where you are constrained to stock width wheels, I run a square tire setup, 275/35-18 all around, for balance and net grip reasons, with 8.5 front and 9.5 rear wheel widths. Even though the fronts are pinched a bit on 8.5" OEM sized front wheels (non-ZCP) and they give up some of the taught feel of an OEM sized front tire, they make up for it in peak grip and braking. Hence in this situation, 275/35-18s all around yield a good bit of gain in grip and hence quicker times on an autox course even though the fronts loose some in transient response.

Hence it's likely that on a carefully measured autocross course with an excellent driver, one could eek out a better time with 255/35-19,275/35-19, versus the OEM sizes even though there might be a small loss in transient conditions (which on course you can make up for by turning sooner and anticipating/accommodating a slightly sloppier response).

Thanks for your input, it's clear you know a helluva lot about tires and wheels! Anyway, I now don't feel so bad about going back to the OEM setup 245/265, heck maybe I might even notice a slight improvement in crispness/responsiveness.

[mmbv1000]

Wow didn't realize it was this bad. I couldn't find any on tirerack but was lucky enough to pick up Costco's last pair - they said they very last two they had in all their warehouses. $20 cheaper than tirerack too. I should put these on a mantle.

[YolkyPalky]

Originally Posted by sansin

Wow didn't realize it was this bad. I couldn't find any on tirerack but was lucky enough to pick up Costco's last pair - they said they very last two they had in all their warehouses. $20 cheaper than tirerack too. I should put these on a mantle.

Yea my local Costco said not available in stock (or any surrounding warehouses) or available to order from Michelin.

Also, my Costco told me, actually repeatedly when I asked asked on separate occasions, that Costco will no longer just sell just two rear tires of Michelin. Apparently Costco has a policy now of only selling a complete set of four tires from Michelin. The manager flat out told me he is not allowed to sell just two rear tires and not replace the fronts as well. I guess you didn't run into this? He actually pulled out some kind of Costco Tire "policy book" and showed me the policy. I didn't really care because I buy all my tires at Discount Tire, which will happily sell rears only (I average 2 sets of rears for every 1 set of fronts), but I found it odd that Costco is claiming they can only sell Michelin in sets of four. Maybe its a California rule too, who knows.

[mmbv1000]

wow - no i didn't have that issue. they shipped them over from their reno warehouse. no questions other than they really couldn't understand why i didn't want them installed there.

i seriously hope michelin gets it together and starts making this size soon!!!