(perhaps this would make a good sticky)
4C Tire Reviews, the tires we've used on our 4Cs and what we thought about them.
Tire reviews are always helpful. Questions plentiful, answers sometime limited.
There are many good posts scattered in this wonderful forum about tires, but buried deep and hard to find. Our 4C has a unique tire size, at least the rear 19s anyway. What's available, what will actually fit, what works well or doesn't work at all?
Before I get into a review of my own, I thought I'd write (talk?) about tire basics. I know there are other people with excellent knowledge and I hope they chime in as well. But don't take our words as the only real views, there's plenty of good reading on the net and in books. Tire Rack has lots of wonderful, easy to read information about tires.
http://www.tirerack.com/content/tirerack/desktop/en/research_advice.html
There are street tires and there are competition tires.
Competition tires are a subject all to their own and deserve a thread of their own. They are not street legal, seldom have tread, and have minimal traction when cold and best grip when extremely hot.
Street tires have been tested and approved by a government agency for your area. In the USA it's DOT (Department of Transportation). They have tread and work best in cool to warm temperatures. Snow tires work best in ice cold temperatures.
All tires have numbers on the side, which can be a mystery to some people. I'll try to explain.
Tire Size: ie 185/75R14
'185' is the section width. The widest part of the tire where it bulges at the sidewall. This is a metric number, 185 mm. Section width is not tread width.
'/' is more than just a separator. It's also a math operator as you'll see in the next sentence.
'75' is the aspect ratio. This is a percentage or a division. The sidewall height is 75% of the section width. In this example the sidewall is 139 mm tall.
'R' indicates it's a radial tire. Usually there is another letter leading the 'R' such as 'SR'. The 'S' is a speed rating. A 'V' tire can sustain higher speeds than an 'S' tire. There are non-radials using this system and then it would just be an 'X'. (185/75x14). A tire without a speed rating can not be used faster that 65 or 70 MPH, which is the maximum speed allowed in most of America.
'14' is the bead size as measured where the tire touches the rim. This is in inches. Don't ask why we mix Metric and American Standard cause I don't know.
Over the years, there have been many different tire size systems. I used the above example because that's the system our 4C uses.
If you read the fine print, you'll find a load rating. When buying new tires, make sure the new tires can carry the same load as the OEM tire, or more. This is very important if you want to use a different size. This is not a static load. As the car turns, brakes and goes over bumps, the tires load and unload. In some situations, a single tire may need to carry half the weight of the car. Our 4C weighs about 2500 pounds, but all four tires added together equals 5048 pounds, about twice the car.
You'll also notice the load is with a certain air pressure, maybe 50 pounds. This second number is the maximum air pressure you can safely put in the tire. As the pressure drops, so does the ability to carry a big load.
Most of us here have a scare story or two about somebody that put undersized tires on their car and didn't live to tell the tale. Don't do it!
One of the things that's important to look for is the tread wear rating. This is somewhat new, maybe ten years or less. Not all tires have this rating. They're either very old, or rock hard. In any case, you don't want them. Usually you'll find 'UTQG' followed by the tread wear rating number followed by traction grade followed by temperature grade. Our P-Zero is UTQG 220 AA A. In this example, AA & A are the best ratings possible. The 220 is arbitrary and deserves an explanation.
By location, the 'AA' is Traction Grade and the 'A' is Temperature Grade.
Tread wear rating number is a measure of how fast the tread wears out. The smaller the number, the faster it wears. I've seen number from 500 to 60. Long lasting tires have less grip, it's a harder rubber compound. Tires with lots of traction have a soft compound and wear quick. Race compound rubber actually rolls off in strings and balls hitting the following cars. It's hot and sticky leaving black streaks on the other race cars.
So, this tread wear rating is only a guide. What do you want? A tire that lasts 60,000 miles and has no traction in the canyons? Or a tire that can hug the twisties but wear out in 15,000 miles? 500 vs 220. The good news is there are tires with 300 ratings. I'm just saying that you have choices.
Staggered set is when all four tires are not the same size. It may have started in NASCAR where they use four different tire sizes. But it usually means that the rears are wider or taller. In the case of our 4Cs, the rears are wider and taller than the fronts.
As of this writing (July 2016), there isn't much of a tire selection for the 18/19 combo. I'm not sure what's available to fit the 17/18 combo. I found that going up one size offers a better selection.
205/45ZR17 --> 215/45ZR17
235/40ZR18 --> 245/40ZR18
205/40ZR18 --> 215/40VR18
235/35ZR19 --> 245/35VR19
Tires, for a given size, have a window or a minimum and maximum allowed tolerance. Some manufacturers choose to make a smaller tire so they can sell it for less money. Another may choose to build the largest allowed to claim better grip or more tread life. Yet another may just make their tire the exact size it says. This effects tire weight, life, grip, price and maybe fitment.
Tread width isn't mentioned and there is no number or marking on the tire that tells the consumer what the actual tread width is. This effects contact patch and rolling resistance.
To find all these things, and more, Tire Rack (no, I don't get paid by Tire Rack, it's just a very informative site) has almost all these specs listed. You can also go to the tire manufacturer web site. Find the tire size and model you're interested in and they will list all these numbers.
The weight of the tire matters. This is un-sprung weight. How fast the tire/wheel goes up and down as the road moves under the car effects not just the passenger comfort, but traction as well. If the tire can't stay on the ground (heavy tire), you can't have good traction. Tire weight also effects rolling resistance and reciprocating mass. This directly effects acceleration and braking as well as turning, especially tight serpentine turns. A low tire weight is a good thing.
Driver reviews usually include, but are not limited to:
Road noise: Usually a tread pattern thing. Not all tires are quiet.
Grip: Traction. Want to go fast(er) in the turns?
Stability: Tram-lining, darting. Does the car feel stable in a straight line or is it darting and wondering?
Longevity: How long did the tires last?
4C Tire Reviews, the tires we've used on our 4Cs and what we thought about them.
Tire reviews are always helpful. Questions plentiful, answers sometime limited.
There are many good posts scattered in this wonderful forum about tires, but buried deep and hard to find. Our 4C has a unique tire size, at least the rear 19s anyway. What's available, what will actually fit, what works well or doesn't work at all?
Before I get into a review of my own, I thought I'd write (talk?) about tire basics. I know there are other people with excellent knowledge and I hope they chime in as well. But don't take our words as the only real views, there's plenty of good reading on the net and in books. Tire Rack has lots of wonderful, easy to read information about tires.
http://www.tirerack.com/content/tirerack/desktop/en/research_advice.html
There are street tires and there are competition tires.
Competition tires are a subject all to their own and deserve a thread of their own. They are not street legal, seldom have tread, and have minimal traction when cold and best grip when extremely hot.
Street tires have been tested and approved by a government agency for your area. In the USA it's DOT (Department of Transportation). They have tread and work best in cool to warm temperatures. Snow tires work best in ice cold temperatures.
All tires have numbers on the side, which can be a mystery to some people. I'll try to explain.
Tire Size: ie 185/75R14
'185' is the section width. The widest part of the tire where it bulges at the sidewall. This is a metric number, 185 mm. Section width is not tread width.
'/' is more than just a separator. It's also a math operator as you'll see in the next sentence.
'75' is the aspect ratio. This is a percentage or a division. The sidewall height is 75% of the section width. In this example the sidewall is 139 mm tall.
'R' indicates it's a radial tire. Usually there is another letter leading the 'R' such as 'SR'. The 'S' is a speed rating. A 'V' tire can sustain higher speeds than an 'S' tire. There are non-radials using this system and then it would just be an 'X'. (185/75x14). A tire without a speed rating can not be used faster that 65 or 70 MPH, which is the maximum speed allowed in most of America.
'14' is the bead size as measured where the tire touches the rim. This is in inches. Don't ask why we mix Metric and American Standard cause I don't know.
Over the years, there have been many different tire size systems. I used the above example because that's the system our 4C uses.
If you read the fine print, you'll find a load rating. When buying new tires, make sure the new tires can carry the same load as the OEM tire, or more. This is very important if you want to use a different size. This is not a static load. As the car turns, brakes and goes over bumps, the tires load and unload. In some situations, a single tire may need to carry half the weight of the car. Our 4C weighs about 2500 pounds, but all four tires added together equals 5048 pounds, about twice the car.
You'll also notice the load is with a certain air pressure, maybe 50 pounds. This second number is the maximum air pressure you can safely put in the tire. As the pressure drops, so does the ability to carry a big load.
Most of us here have a scare story or two about somebody that put undersized tires on their car and didn't live to tell the tale. Don't do it!
One of the things that's important to look for is the tread wear rating. This is somewhat new, maybe ten years or less. Not all tires have this rating. They're either very old, or rock hard. In any case, you don't want them. Usually you'll find 'UTQG' followed by the tread wear rating number followed by traction grade followed by temperature grade. Our P-Zero is UTQG 220 AA A. In this example, AA & A are the best ratings possible. The 220 is arbitrary and deserves an explanation.
By location, the 'AA' is Traction Grade and the 'A' is Temperature Grade.
Tread wear rating number is a measure of how fast the tread wears out. The smaller the number, the faster it wears. I've seen number from 500 to 60. Long lasting tires have less grip, it's a harder rubber compound. Tires with lots of traction have a soft compound and wear quick. Race compound rubber actually rolls off in strings and balls hitting the following cars. It's hot and sticky leaving black streaks on the other race cars.
So, this tread wear rating is only a guide. What do you want? A tire that lasts 60,000 miles and has no traction in the canyons? Or a tire that can hug the twisties but wear out in 15,000 miles? 500 vs 220. The good news is there are tires with 300 ratings. I'm just saying that you have choices.
Staggered set is when all four tires are not the same size. It may have started in NASCAR where they use four different tire sizes. But it usually means that the rears are wider or taller. In the case of our 4Cs, the rears are wider and taller than the fronts.
As of this writing (July 2016), there isn't much of a tire selection for the 18/19 combo. I'm not sure what's available to fit the 17/18 combo. I found that going up one size offers a better selection.
205/45ZR17 --> 215/45ZR17
235/40ZR18 --> 245/40ZR18
205/40ZR18 --> 215/40VR18
235/35ZR19 --> 245/35VR19
Tires, for a given size, have a window or a minimum and maximum allowed tolerance. Some manufacturers choose to make a smaller tire so they can sell it for less money. Another may choose to build the largest allowed to claim better grip or more tread life. Yet another may just make their tire the exact size it says. This effects tire weight, life, grip, price and maybe fitment.
Tread width isn't mentioned and there is no number or marking on the tire that tells the consumer what the actual tread width is. This effects contact patch and rolling resistance.
To find all these things, and more, Tire Rack (no, I don't get paid by Tire Rack, it's just a very informative site) has almost all these specs listed. You can also go to the tire manufacturer web site. Find the tire size and model you're interested in and they will list all these numbers.
The weight of the tire matters. This is un-sprung weight. How fast the tire/wheel goes up and down as the road moves under the car effects not just the passenger comfort, but traction as well. If the tire can't stay on the ground (heavy tire), you can't have good traction. Tire weight also effects rolling resistance and reciprocating mass. This directly effects acceleration and braking as well as turning, especially tight serpentine turns. A low tire weight is a good thing.
Driver reviews usually include, but are not limited to:
Road noise: Usually a tread pattern thing. Not all tires are quiet.
Grip: Traction. Want to go fast(er) in the turns?
Stability: Tram-lining, darting. Does the car feel stable in a straight line or is it darting and wondering?
Longevity: How long did the tires last?