whatthefoie

iTrader: (3)

hey guys,

my michelin PSS and coupe 19's are on my sedan and its awesome. before i bought my tires the service guy at the dealership said to NOT get the michelin PSS. he said that the camber on the coupe is different on the sedan so there will be uneven wear and the life of the tire will be drastically reduced. i went ahead and got the michelin's anyway reading all the positive things about them on these boards. is what he said true??

soundmike

iTrader: (6)

Not so much the camber issue, but that they're staggered as well. Michelin only warranties up to 15k with that set-up.

30k if you run a square set-up. If you're not dropped, camber should not be too big of an issue, just keep toe in check. If you really want to reduce camber, get a kit.

AroundTheG37

iTrader: (8)

Don't listen to that bozo, he is just a talking head. Now, he is somewhat right on experiencing more tire wear but the only reason for that is you won't be able to rotate your tires (due to the fact you now have staggered tire widths) like you could with your oem wheels. However, you can take the rear tires completely off the wheel and flip them to the other side once you start seeing significant inner tire wear (check periodically). There is usually a charge for that but if you bought them at discount tire explain to them that you can't take advantage of their free rotations and that you will most likely only be doing this one time (due to the fact you might only get 25k out of them). As for the guy not recommending the PSS because of tire wear, the only thing I can say about that is he has no idea what he is talking about and usually that's the case with the blockheads at the dealership. Now let's see some pics!

JSolo

iTrader: (14)

If it were me, and i was keeping to stock sizes, I'd just go 245/40/19 all around.

According to tirerack's michelin pss's spec, recommended wheel width's for the above size is 8-9.5"

The sport coupe comes with 8.5" wheels in the front and 9.5" in the rear. Both fit within the recommended range.

This will let you easily rotate tires front/rear.

My sedan came with 7.5" front and 8.5" rear (in 18" size). Recommended wheel width for the 245/45/18 (which is what the sedan takes on the rear) is 7.5 - 9.0", so once it's time for new rubber, i'll just put 245's all around.

ymmv

sniper27

iTrader: (2)

I wondered about this. I hear people running a square setup on staggered wheels. So you rotate your squared tires with staggered wheels? What are the effects of putting the 9in wheels with 45 offset in the front and 8.5 wheels with 43 offset in the rear. Will it look odd? Drive differently? Even with a squared setup tires?

JSolo

iTrader: (14)

^^Valid point.

Can't answer that until this winter when it's time to swap the snow tires back on. Prior to doing so, will swap the rears to the front.

The offsets are not that huge, only 2mm difference, so doubt it would be an issue. As for the 1" wider wheels being in the front, if you think about it, it should only stick out 1/2" past center *more* than the 8.5" wheel. I don't know how noticeable this 1/2" difference would be.

The big question is how significant will the change in handling be... Steering wheel effort might increase slightly because of the larger contact patch in the front. Would there be more/less over/understeer now?

Another option to consider is going square setup, but not rotating. I think the only benefit of this would be the increased steering effort (which on the sport sedans seems very easy - and the coupes I've test driven feel similar as well).

soundmike

iTrader: (6)

There is no need to dismount/remount the PSS. Outside will always be outside regardless of location.

soundmike

iTrader: (6)

You can always just dismount/remount the tires on opposing sides yet keeping the staggered wheel where they are (narrow front, wide rear.)

Also, do note there's more to tire widths than the wheel width itself. IIRC, there's a 0.2" difference in overall width from one wheel width size to the next.

That is, for the sake of simple argument, if your tire was measured to be 10" on an 8" wide wheel.

It would then be 10.2" wider on an 8.5" wheel, and 9.8" wide on a 7.5" wheel.

So, theoretically there is a 0.4" width change between front and rear with your proposed set-up.

Tires and offsets are funny, you won't notice much a difference. with daily driving, likely. But it will affect oversteer/understeer. If staggered sizes didn't matter that much in these sizes, no car manufacturer would provide wider set-ups in the rear of RWD cars. Too narrow a rear compared to the fronts will likely have the rear fish-tail on you.

JSolo

iTrader: (14)

The question then becomes, what is this threshold. Although it would be a square set up in terms of tire sizes front and rear, the contact patch would be slightly less when mounted in a narrower wheel. This should not be an issue so long as the wider wheel remains in the rear.

Seems there's no easy solution. Perhaps one possible alternative with a square setup is swap the physical tires between the front and rear wheels at some midpoint in their lifecycle. There might be additional cost, but usable tire life should be extended.. ?

Edit: Mike, I think that's what you meant by your first line above ?

AroundTheG37

iTrader: (8)

Look a little closer at my post. I said he has to take the tire completely off the wheel and remount it onto the other wheel. If you move the driver side rear tire to the rear passenger side the inside of the tire will now be on the outside. People have a hard time understanding this concept though. It's funny you mention this because when I explained it to discount tire they were still trying to just rotate the wheels/tires. I had to go out there and show them exactly what I wanted.

soundmike

iTrader: (6)

I don't really know what that threshold would be. FWIW, we all probably adjust the balance just as much with the various tweaks we make to swaybar stiffness, drop height, spring and damper stiffness, etc.

Yep, that's what i meant. For the lack of a clearer definition, just imagine your wheels to be welded to their hubs, you'd just be rotating the tires themselves in an x-pattern via dismount/re-mount.

PSS tires are assymetric non-directional. Dismounting them then re-mounting them to an opposite side would still mean the marked "Outside" wall will still face out. Theoretically you can have the outside wall face in, as in how you described it, but it will affect how the tire performs -- especially with the PSS where 3/4 of the inner tread is an all-season compound and the 1/4 outer tread is a summer compound with larger blocks for cornering traction.

The method you mention usually only applies to directional tires like the Hankook V12's, which does not specify an outside or inside wall.

With a staggered PSS set-up, you literally flip the entire mounted tire/wheel onto the other side and it's the same thing as dismounting the tire and re-mounting it, but without the extra hassle and cost.

sniper27

iTrader: (2)

Maybe I'm not visualizing it. But what is the benefits of that? Say you have inside tire wear. If you flip the entire mounted tire/wheel to the other side, wouldn't the inside tire wear still be inside on the other side?

Neal@tirerack

iTrader: (2)

The PSS is an excellent tire and it's good that you bought them.

whatthefoie

iTrader: (3)

wow thanks for all the replies guys, this is great stuff in here and i hope this helps other people in the future! and yes! i will take pictures later today and post em up!

soundmike

iTrader: (6)

Correct. Flipping it to the other side, at least with PSS, will still have the inside tread stay on the inside. The only advantage to flipping is that each corner affects tire wear differently. So if one corner is wearing down faster, moving that to a different corner will slow down that tires wear rate.

Basically, you'd be distributing the wear rates evenly between flipped sides.

For staggered set-ups, the rears will almost always wear faster, even when flipped like this, because of the natural aggressiveness of the rear alignments compared to the fronts.