[CSBM5]

Originally Posted by Carrera2RS

Where do they pubish the force vs slip angle info, this takes me back to my automotive engineering degree days !

I've not seen this specific comparison published anywhere. I was creating the graph in my mind from driving/experiencing the two tire designs on three different platforms (E39 M5, E90 M3 and M2C).

[///MPhatic]

Originally Posted by CSBM5

In other words, the PS4S feels "less responsive" to steering inputs compared to the PSS even though if you fully exploit the tire on track, it's faster than a PSS.

I haven't read this at all. The PSS should be slightly faster than the PS4S on track from what I've read. But certainly the feel of the two tires would be quite different.

I actually don't even understand talking about the PSS/PS4S and track days. If you can afford an M2/3/4 it stands to reason that you can afford a proper set of drive-to-and-from track tires for your track day.

[CSBM5]

Originally Posted by ///MPhatic

I haven't read this at all. The PSS should be slightly faster than the PS4S on track from what I've read. But certainly the feel of the two tires would be quite different.

I actually don't even understand talking about the PSS/PS4S and track days. If you can afford an M2/3/4 it stands to reason that you can afford a proper set of drive-to-and-from track tires for your track day.

I'm just relaying information from tire tests performed by TireRack and Tyre Review in addition to Michelin's own published comparisons. The PS4S will lap faster than a PSS on both a dry and wet track.

I agree with you completely on track use. I can't even recall the last time I drove a street type tire on a track (unless you're talking about autocrossing and TW200 tires like RE-71Rs). I bought the first R-compound tire introduced back in 1985 (Goodyear Gatorback S with its molded 4/32" tread and all) and never looked back.

[ZM2]

Having run both tires on track many times when either my track tires were burned up, or for heavy rain, or in extra cold weather, and even in light snow on track, the PS4S is slightly faster than the PSS in the dry, a decent bit quicker in the wet, and has higher grip levels in the cold.

The PS4S is also quieter, more comfortable, and lasts longer than the PSS (>20K road miles for me on each). The only thing the PSS has going for it is better turn in and responsiveness.

I'll switch to the Conti SportContact 7 or PS5S for my daily driving and bad weather track tire, whenever either of those make it to the US.

[///MPhatic]

Originally Posted by CSBM5

I'm just relaying information from tire tests performed by TireRack and Tyre Review in addition to Michelin's own published comparisons. The PS4S will lap faster than a PSS on both a dry and wet track.

I agree with you completely on track use. I can't even recall the last time I drove a street type tire on a track (unless you're talking about autocrossing and TW200 tires like RE-71Rs). I bought the first R-compound tire introduced back in 1985 (Goodyear Gatorback S with its molded 4/32" tread and all) and never looked back.

Maybe it was the earlier reviews that I was remembering. Even the PS4S is an old tire now. I prefer their feel for sure, but the PS4S makes more sense for me as a daily. Unfortunately, I got the new V601 with my last set of wheels, so they'll be on for a while.

Anyone that knows enough to run a 71R is a friend of mine. Old tech or not, they are still my favorite street/track tire. I wish they would hurry up and give us the S in the US.

I too had Gatorbacks, we're going way back now. I did prefer the look of the P7 (iconic IMO), and the grip of the A008 (put everything to shame), but the Gator's were awesome for sure.

[CSBM5]

Originally Posted by ///MPhatic

Maybe it was the earlier reviews that I was remembering. Even the PS4S is an old tire now. I prefer their feel for sure, but the PS4S makes more sense for me as a daily. Unfortunately, I got the new V601 with my last set of wheels, so they'll be on for a while.

Anyone that knows enough to run a 71R is a friend of mine. Old tech or not, they are still my favorite street/track tire. I wish they would hurry up and give us the S in the US.

I too had Gatorbacks, we're going way back now. I did prefer the look of the P7 (iconic IMO), and the grip of the A008 (put everything to shame), but the Gator's were awesome for sure.

Yeah, it was the "S" compound version of the Gatorback that was a really sweet tire in 1985...no need to shave them either. Not too long after that Yokohama released the r-compound version of the A-008, the A-008R, and I switched to those. I daily drove on those tires for years too.

Speaking of the RE-71R, I still have a set mounted on a 2nd set of wheels for the M2C but haven't had a chance to use them for over a year now. Fun tires for sure, and what a difference in steering response vs PS4S.

EDIT: Found it! A pic of my Bavaria with the A-008Rs mounted!

[///MPhatic]

Originally Posted by CSBM5

Yeah, it was the "S" compound version of the Gatorback that was a really sweet tire in 1985...no need to shave them either. Not too long after that Yokohama released the r-compound version of the A-008, the A-008R, and I switched to those. I daily drove on those tires for years too.

Speaking of the RE-71R, I still have a set mounted on a 2nd set of wheels for the M2C but haven't had a chance to use them for over a year now. Fun tires for sure, and what a difference in steering response vs PS4S.

EDIT: Found it! A pic of my Bavaria with the A-008Rs mounted!

That's what I meant, A008R! I had them on my Conquest TSi.

Bavaria, wow.

I wish I could find a new leftover set of 71R's.

EDIT: You'll appreciate these...

[Wise1208]

So I just went from the * rated PSS to the non * PS4S today and after the first drive wanted to add what I noticed right away.

1. Ride is much better to the point where you will think the roads you normaly drive have been repaved. That much better.

2. From a dead stop grip is better. Not better then my old tires but better then when my PSS were young.

3. The negative. Turn in is noticeably softer that crisp nose dive and the road feel is muted.

[ZCPMV8]

I'm about to do the same and upgrade to the PS4Ss. There's the Mercedes spec and normal spec on tire rack. Is it obvious to avoid the MO1 version simply because we are driving BMWs? Anyone know the difference?

[ThreeStripes]

Originally Posted by Wise1208

3. The negative. Turn in is noticeably softer that crisp nose dive and the road feel is muted.

Perhaps it’s because of the aggressive camber I run up front in combination with the TCK suspension kit but I didn’t find turn in and road feel to be impacted much if at all.

For me the PS4S was a no compromise upgrade in stock sizes.

[Ratcher]

Originally Posted by Wise1208

So I just went from the * rated PSS to the non * PS4S today and after the first drive wanted to add what I noticed right away.

1. Ride is much better to the point where you will think the roads you normaly drive have been repaved. That much better.

2. From a dead stop grip is better. Not better then my old tires but better then when my PSS were young.

3. The negative. Turn in is noticeably softer that crisp nose dive and the road feel is muted.

This 100%. Also when warm, the grip is identical between both.

[ZCPMV8]

Originally Posted by Ratcher

This 100%. Also when warm, the grip is identical between both.

Is wet performance that much better? Enough to make one say that these are actually good in the rain for perf tires.. Or is it a bit overblown due to the fact that super sports are so terrible in wet conditions?

[Ratcher]

Originally Posted by ZCPMV8

Is wet performance that much better? Enough to make one say that these are actually good in the rain for perf tires.. Or is it a bit overblown due to the fact that super sports are so terrible in wet conditions?

PS4S are really good in the wet. Only better tire I know is the A052, surprisingly.

[ZCPMV8]

Originally Posted by Ratcher

PS4S are really good in the wet. Only better tire I know is the A052, surprisingly.

Thanks for the info! Good to know.

[gokusan]

Hello,

did somebody put MO or MO1 PS4S on F87? Or did somebody compare MO vs *?

[Rat_House]

My 2 cents, I have the PSS on my M2 and the PS4S on my R8. The PSS have a much more firm sidewall than the PS4 so the ride feels a little stiffer but turn in / turning at speed feels more direct but traction breaks quickly at the limit. The sidewall flex in the ps4s makes breaking traction at the limit a little more forgiving. The PSS do have superior traction tho in colder temps like 40-50f. When my rears wear out I’m going with the PSS.

[///MPhatic]

Originally Posted by Rat_House

The PSS do have superior traction tho in colder temps like 40-50f.

Did you write this incorrectly? PS4S should easily out-perform the PSS as the temps lower.

If this is in fact what you're experiencing I'd say it's because you're not comparing apples to apples, ie the tires have different mileage on them, maybe different driving styles, and are on different cars.

The PS4S should be the clear winner as the temps lower. It's a true 300 tw tire, whereas the PSS is a lie at 300 tw, more like 280 or 250 with regards to grip/how it wears/how it handles cold/rain, etc.

[Rat_House]

Originally Posted by ///MPhatic

Did you write this incorrectly? PS4S should easily out-perform the PSS as the temps lower.

Nope that’s my experience. Mileage on the tires are different tho, about 5k on the ps4s and 15k on the pss, and yeah 2 different vehicles one front engine Rwd and one mid engine awd. Tire sizes were also different, 245/265 on the pss and 245/305 ps4s.
But on the cooler mornings before the tires warmed up I would get a lot of front end scrub on the ps4s and the rear would easily step out on throttle around turns. The only issue I would get on the pss was some wheel hop accelerating from a stop in 1st gear.
So I guess you could say lateral grip on the ps4s when cold is worse than the pss but straight line traction was better on the ps4s than the pss.
This was the case even when the pss were new tho, so not sure mileage really made a difference.

[///MPhatic]

Originally Posted by Rat_House

Mileage on the tires are different...5k to 15k...and yeah 2 different vehicles...one front engine Rwd and one mid engine awd...tire sizes were also different...

This confirms that your experience is bespoke to you. The PS4S performs better in the rain, and in colder temps than the PSS when compared apples to apples on the same car from new. The best part is that the PS4S keeps its edge for longer too, because of better wear characteristics.

[Rat_House]

Originally Posted by ///MPhatic

This confirms that your experience is bespoke to you. The PS4S performs better in the rain, and in colder temps than the PSS when compared apples to apples on the same car from new. The best part is that the PS4S keeps its edge for longer too, because of better wear characteristics.

Hahaha tire characteristics are tire characteristics and aren’t going to change depending on which vehicle they’re on. Case and point sport cup 2 always have the same customer feedback whether they’re on a 911 or m4. You sound like someone is paying you to push the ps4s.

[CSBM5]

Having switched four cars from PSS to PS4S, there's no question the PS4S is better performing in cooler temperatures especially in longitudinal grip. Michelin confirms that observation with their own testing as it was one of the design goals with the tire compound.