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From what I read on the Michelin site, both PS 4 and PS 4S have "hybrid" technology. For me this also sounds more like marketing, but the performance is there.

Compared to the PS 4, the PS 4S is optimized for better grip in the dry, it has a softer compound that wears faster. And wet performance is a little weaker, but still very good. This also means that the PS 4 should last a little longer. The new Goodyear range seems as good as the Michelins (and Continental) though. You can't go wrong with any of them. Look at the videos on the TyreReviews Youtube channel, they looked and compared the tyres mentioned.

And I second alfaitalia. The toe setting has more impact on tyre wear than camber. You're looking at a still standing car, while most wear mainly happens when driving and cornering and loads constantly varying from one side to the other.
 

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Discussion Starter #22
I agree all good tires. I didn't tink/realize the PS4 had the hybrid though - interesting if it in fact does, as the inside half (on the PS4S) is supposed to be more for "wet" so you'd have to assume maybe its a bit softer - interesting.

So for maybe the last time on this thread - I have ZERO toe-in none, nada, nothing, zero - absolutely dead straight. I do have negative 1.5 degrees camber on all four wheels (plus or minus a few minutes) and the inside of my tires are worn. This has been the case all the years I have owned it. So there is NO TOE-IN or TOE-OUT on this car - its ZERO, thus the ONLY reason my car wears the insides is the CAMBER setting. It just cannot be plainer or simpler than this, how does anyone even bring this up as some kind of "argument" beats the hell out of me.
 

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Ok now you just said something that really hit home! I love these forums for getting new ideas!!!

My whole initial reason to look at this topic of "do different tire technologies make a difference in inside edge tire wear - everything else remaining equal" because with this last set of tires I seemed to feel the inside edge wore out more than with previous tires. Because I rotate the tires every 5000 kms I can't tell if it was from the front or rear. I do get an alignment every 10,000kms and know my alignment is right at negative 1.5 degrees at each corner. So I assumed all wheels will wear the inside edge about the same.

But something in the back of my mind had me thinking "I wonder if these PS4's have something to do with it".

You said that worn suspension (bushes etc) could cause some movement. Maybe there is a worn component which has created a new issue which wasn't there when the car was younger. So I will now take the car to a suspension specialist and get it thoroughly checked out to see if any worn components are causing an issue, before getting my next set of tires.

Thanks so much for the comment. Made me think.
I think given the latest of these cars are about 9 years old now - there's a good chance a lot of suspension bushes are wearing or worn - I think the rear bushes are considered (I use 'considered' as I'm not an expert on these matters) a bad design even when new - have a look at these 2 videos showing the comparison.


 

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I have a Q4 TI the suspension may well be different. I have zero degrees toe-in and negative 1.5 degrees camber on all 4 wheels. It's the negative CAMBER that causes inside edge tire wear. Think about it negative 1.5 degrees means the wheel is not vertical, the top is leaning into the cars centre so that means the inside edge touches and the outside edge does not. Its simple physics and it doesnt change if 10000000 people say otherwise, physics is physics. Sorry but negative camber causes inside edge wear. This is a very simple fact. As I said before if you add toe-in (which is what my ti suspension had not toe-out) it will worsen the tire wear. But I have it set to zero anyway, so mute point here.

So once again, I'm not here to debate wheel alignment. What I am curious to know is if a hybrid tyre compound can minimize inside edge wear without changing any alignment settings. That's all I'm curious about.

This new hybrid technology- like the Michelin Pilot Sport 4S - has a different compound on the out edges compared to the center part of the tread. So am just curious on real life experience with this technology.
In my experience front wheel inside edge tyre wear is because of the front lower wishbone rear bushes being too soft. Your tracking / wheel alignment set to zero toe means nothing because that is measured when the car is stationary. When the car is moving there will be lots of toe-out because the rear bushes on the wishbones are so soft. Only the 159/Brera/Spider have these big floppy bushes, the 156/147/GT didn't, the GTV/Spider didn't, even the 166 didn't. They all had small, precise bushes with very little movement bar the rotational movement of the wishbone moving up and down. This keeps the wheel pointing in the direction it is set. On the 159 they toe out when in motion.
 

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Actually the toe in becomes less under accelerating due to the front wheels being pulled forward and in....rear wheel drive cars gain toe out under power as the front tyres are pushed out and back. Which is why generally front drive cars come with toe out and rear drive come with toe in from the factory. But as said a combination of too much toe out and the soft bushes do allow too much movement. I don't have poly bushes but don't have any inner tire wear having set my toe to just the tiniest bit of toe out. I found zero toe made her a bit vague under power and turn in.
 

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Discussion Starter #26
Wow thanks to the many responses, you guys are great. I am so glad I started this post.

I initially was thinking about tires, as I really have noticed this last set wearing more than the previous ones on the inside - alignment has always been checked. I was just not aware of some of the "flaws" in the 159 suspension - like the rear control arm bush on the front suspension that would flex and cause some toe-out as you drive. Combined with some likely wear on the suspension overall - it may be the contributing factors to why I have noticed more inside edge tire wear with these last set of tires.

I have the car booked in with a suspension specialist to check the status of the suspension and I will certainly be changing those rear control arm bushes.

This also makes a bit more sense why everyone was hounding me about toe-out - logically if the alignment is set at zero and the suspension works as it should it's a mute point, but with this suspension as you drive you'd generate toe-out and scrub the inside edges more.

So a couple of questions:
What specific bushes (or other components) should be upgraded to eliminate these issues?
Are there any recommended "upgrade kits" or anything like that?
What would I tell a suspension specialist (that may not be an Alfa expert) to do to fix the problem(s)?
 

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To put in my 2 cents (pence) worth. As well as a 159 and a GT I have a BMW X5 which has serious negative camber issues on the rear and came with staggered 19" rims (285 45 19 on rear). I was getting about 15,000 kms out of a set of tyres before chewing out the inside edge. I have since bought a set of second hand rims and tyres from a non sports pack X5 which are 235 65 17. When I put them on they were already used tyres and I have done 16,000 kms with them so far and no sign at all of uneven wear.

I put it down to low profile tyres having very little tyre wall to compensate for the camber. Higher profile tyres have more give and thus sit flatter on the road. As a point of interest the X5 handles just as well, if not better with the higher profile tyres as it did with the fat low profile tyres.
 

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Discussion Starter #28
To put in my 2 cents (pence) worth. As well as a 159 and a GT I have a BMW X5 which has serious negative camber issues on the rear and came with staggered 19" rims (285 45 19 on rear). I was getting about 15,000 kms out of a set of tyres before chewing out the inside edge. I have since bought a set of second hand rims and tyres from a non sports pack X5 which are 235 65 17. When I put them on they were already used tyres and I have done 16,000 kms with them so far and no sign at all of uneven wear.

I put it down to low profile tyres having very little tyre wall to compensate for the camber. Higher profile tyres have more give and thus sit flatter on the road. As a point of interest the X5 handles just as well, if not better with the higher profile tyres as it did with the fat low profile tyres.
I've had experiences like that too. I had a 7 series BMW with performance suspension option and about or a bit more negative camber than the Alfa - inside edge wear also. I had a 911 turbo with quite a bit of neg camber on rear, not so much on front - rears wore the inside edge, fronts did not. It's what we live with to get the best handling grip.
I would say higher performance tires will have a tendency to have stiffer (sometimes much stiffer) sidewalls than higher profile/lower performance oriented tires.
 
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