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I have spent weeks looking at this and I just called Alfa Care, no help there. What I have found is that the rear 285/35 size is the real problem here. Yes, there are alternate sizes but we have to keep the wheel circumference the same as in the OE product or we could void our warranty. The issue is the 4 wheel drive system. I have been working with Tire Rack, and there is no solution there. Toyo has come closest but for the rear they have 295/35-21s which would be a different circumference. The other issue is if we go too narrow, there can be concerns about the amount of weight they could carry because of less air in the tire. Tire Rack told me it is not PSI, but volume that matters in this case.

The Scorpion does seem like a choice, but only for 20" rims.
The main thing is to keep front and rear diameters pretty close from one another, you can vary the circumference within 3% and it won't have adverse effects on drivability or warranty. Outside diameter on a 20" wheel for the QV is 29" Front & 29.1" Rear (if I remember correctly). You can do 28.7" on front and rear and car will be fine.

My winter tires are a square setup on 19" wheels @ 29.1" front and rear (the very same Scorpios you posted), that happened by coincidence because I reused the same winter tires I had on my previous Volvo, just replaced the wheels. That is also to say that, for a winter setup, you don't have to keep the staggered setup. With my square setup the car's handling is very slightly affected, yes, but that is the effect of any winter tire too.
 

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Just so I can be sure, can you point me to a place that confirms:

"The main thing is to keep front and rear diameters pretty close from one another, you can vary the circumference within 3% and it won't have adverse effects on drivability or warranty. Outside diameter on a 20" wheel for the QV is 29" Front & 29.1" Rear (if I remember correctly). You can do 28.7" on front and rear and car will be fine."
 

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Just so I can be sure, can you point me to a place that confirms:

"The main thing is to keep front and rear diameters pretty close from one another, you can vary the circumference within 3% and it won't have adverse effects on drivability or warranty. Outside diameter on a 20" wheel for the QV is 29" Front & 29.1" Rear (if I remember correctly). You can do 28.7" on front and rear and car will be fine."
Tirerack has a nice explanation, specifically the last paragraph at the bottom. If you search other posts in this forum you will find that others have also said that 3% is within tolerances.
 

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Tirerack has a nice explanation, specifically the last paragraph at the bottom. If you search other posts in this forum you will find that others have also said that 3% is within tolerances.
Thanks very much for the link, that helps, but does not really say to me 3% is OK with Alfa. As I mentioned in a previous note, I called them yesterday and the only advice they gave me was to call a dealer.

I did find a nice Tire Size Calculator at this URL people might find helpful:


I put in some numbers and confirmed the relationships between sizes that people have been talking about. For example 255/45-20 is identical to 255/40-21 (the size that came on my QV). Sadly, I still have not found a place with in-stock either all season or winter tires. Tire rack is out of a lot of things I looked at. A lot of manufacture sites point you to dealers, but they are out of stock to and don't know when the will get anything new.
 

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Maybe what you could do is compare the diameters of all the wheel/tire brand configurations stelvios are sold with - you can bet there is some variation.
If you ask the alfacares people, they will usually confirm they are neither alfa specialists or car specialists - they are nice and usually helpful customer service people who don't usually know the difference between a jeep and a giulia.
 

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Maybe what you could do is compare the diameters of all the wheel/tire brand configurations stelvios are sold with - you can bet there is some variation.
If you ask the alfacares people, they will usually confirm they are neither alfa specialists or car specialists - they are nice and usually helpful customer service people who don't usually know the difference between a jeep and a giulia.
As far as I know, the QV, only has two options, that may not have always been the case. The examples I gave were for the two different wheel sizes 20 and 21" I think I am going to order some OZ wheels in 20 inch and get scorpion winter tires. Unfortunately the rears wont be in for another 6 - 8 weeks, but I should be OK.
 

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10mm wider only adds 7mm to the diameter of the tire if the aspect ratio is 35. And if you add 10mm in both the front and rear then the ratio between the front a rear stays the same. I would not worry about getting tires that are 10mm wider. You'll probably get a slightly better ride due to more sidewall.
 

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10mm wider only adds 7mm to the diameter of the tire if the aspect ratio is 35. And if you add 10mm in both the front and rear then the ratio between the front a rear stays the same. I would not worry about getting tires that are 10mm wider.
I see what you are saying, it would be closer but then there still would be a difference in revolutions per unit driven, but I would agree is is a small percent, and the speedo would also be off by a tiny percent. I think I am just going to pull the trigger and order the wheel and tire set.
 

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I see what you are saying, it would be closer but then there still would be a difference in revolutions per unit driven, but I would agree is is a small percent, and the speedo would also be off by a tiny percent. I think I am just going to pull the trigger and order the wheel and tire set.
So, if you're looking at winter tire setup...and would like to save money in the process...why don't you go with a square setup like mine?

1- Outside diameter stays the same, technically at +0.1", so your speedometer won't change
2- Because OD stays the same, no Alfa dealer could say anything if there's a warranty type of issue...although, I still fail to see how going down to 28.7" or higher to 29.4" could void your warranty if all tires have same OD. Nobody with a different tire size has reported that incident at this site.
3- You would save money in you are doing it as a second set.

I bought Giulia knock offs from ebay ($800), added a 5mm spacer (to clear front calipers @ $150) and put 235/55-R19s all around ($1,100), which measure 29.2" OD.

Just a thought.
 

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So, if you're looking at winter tire setup...and would like to save money in the process...why don't you go with a square setup like mine?

1- Outside diameter stays the same, technically at +0.1", so your speedometer won't change
2- Because OD stays the same, no Alfa dealer could say anything if there's a warranty type of issue...although, I still fail to see how going down to 28.7" or higher to 29.4" could void your warranty if all tires have same OD. Nobody with a different tire size has reported that incident at this site.
3- You would save money in you are doing it as a second set.

I bought Giulia knock offs from ebay ($800), added a 5mm spacer (to clear front calipers @ $150) and put 235/55-R19s all around ($1,100), which measure 29.2" OD.

Just a thought.
Thanks very much. I ordered the set up I was talking about a few hours ago. It turns out that while I was thinking about it over the past couple of days, they sold out of the rear set of rims. I put my order in anyway. So when the new ones come it, I will be at the top of the list.
 

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Thanks very much. I ordered the set up I was talking about a few hours ago. It turns out that while I was thinking about it over the past couple of days, they sold out of the rear set of rims. I put my order in anyway. So when the new ones come it, I will be at the top of the list.
Nice, what wheels did you get?
 

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I see what you are saying, it would be closer but then there still would be a difference in revolutions per unit driven, but I would agree is is a small percent, and the speedo would also be off by a tiny percent. I think I am just going to pull the trigger and order the wheel and tire set.
I was also assuming that the speedometer would be off, lets say if it was showing 55 mph that the car would be going actually faster, lets say 56 mph since the tire diameter is bigger....but actually the car according to the Waze GPS was going slower at 54 mph with the wider tires.....go figure!!!
 

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Speedometers in the US are off by a couple of MPH at 60 MPH. Don't know the story behind that, perhaps someone else does, but they are always 2 MPH above the GPS speeds, I remember noticing this since the early 2000s.
Carly for BMW (an Androi/Apple coding app) allows you to do speedometer correction as part of the coding options, it was nice!
 

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Speedometers in the US are off by a couple of MPH at 60 MPH. Don't know the story behind that, perhaps someone else does, but they are always 2 MPH above the GPS speeds, I remember noticing this since the early 2000s.
I read somewhere that US regulations heavily penalize speedometer errors that are low. But not if readings are too high. So if the uncertainty is, say, plus or minus 1 mph at 60 mph, then it is safer for the car manufacturers to design it to report 60 to 62, than 59 to 61. That 59 could get then a hefty fine. But the 62 won't.
 

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I think visconti had a knee-jerk reaction as a result of his uhp summer tire incident. Dont worry about it - just dont expect them to be as good as a pirelli winter in real winter; they have a partial snowflake in the individual description, but clearly are "all weather". View attachment 27810
Cinturato has been a sleeper gret tire for years!!!
 
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