a tyre question

[JapRulezz]

if i were to replace my 185/60/r15 on my yaris with 195/55/r15 would that decrease the cars power ?

[ztrack157]

nope. actually makes circumference of the tire smaller. thus less time for one rotation.

[thebarber]

no, no loss in power

[AlexNet0]

does that do anything to your gas mileage? Putting smaller tires on?
Theory tells me it would, but I dont know by how much.

ignore me please if this is a stupid question, lol

[thebarber]

does that do anything to your gas mileage? Putting smaller tires on?
Theory tells me it would, but I dont know by how much.

ignore me please if this is a stupid question, lol

would really affect economy....over size is pretty much the same....195-55 tire might be a bit heavier, but i wouldnt think itd be different enough to make any kind of a change except the wider rubber would grip better in handling...

[kimona]

185/60/15 = 23.7

195/55/15 = 23.4

205/55/15 = 23.9

This information is in the "official wheel and tire guide" in the sticky in this section.

[ztrack157]

It would screw with your speedometer as well. Unless you hav a scangauge or something to correct it.

[ddongbap]

It would screw with your speedometer as well. Unless you hav a scangauge or something to correct it.

MM.. I'm pretty sure a scangauge wouldn't fix that problem.

[JapRulezz]

i did it people , and i feel a great deal more handling and stability , i asked the Question because although the less time for rotation , theres a increase in rubber width .... so who wins?
PS : i didnt understand that ''23.7'' thing by kimona

[YarisSedan]

Your bottom end and off the line acceleration will benifit slightly. Your top speed will decrease as well as your top end fuel milage. Larger diamter will give you higher top speed and better economy on freeway speeds. If you do local driving and no more than 40mph then you will benifit from this. If you speed most of your time commuting you would be better off with a larger diamter size. Especially if you drive a automatic which is already geared twoards city driving.

[kimona]

i did it people , and i feel a great deal more handling and stability , i asked the Question because although the less time for rotation , theres a increase in rubber width .... so who wins?
PS : i didnt understand that ''23.7'' thing by kimona

Sorry. I was giving you diameter in inches so you could make a comparison among tyre sizes. The most common upgrade is from 185/60/15 to 205/55/15... because it is closest to OEM diameter.

Speedo error is not of concern with these tyre size changes. In fact, there is speedo error right out of the box with the Vitz/Yaris with OEM 14, 15, and 16 inch diameter wheels/tyres.

[Russelt3hPirate]

Sorry. I was giving you diameter in inches so you could make a comparison among tyre sizes. The most common upgrade is from 185/60/15 to 205/55/15... because it is closest to OEM diameter.

Speedo error is not of concern with these tyre size changes. In fact, there is speedo error right out of the box with the Vitz/Yaris with OEM 14, 15, and 16 inch diameter wheels/tyres.

No car has an accurate speedo and the faster you go the less accurate they are.

as long as someone doesn't go too crazy it wont be a "real" problem.

[JapRulezz]

Sorry. I was giving you diameter in inches so you could make a comparison among tyre sizes. The most common upgrade is from 185/60/15 to 205/55/15... because it is closest to OEM diameter.

Speedo error is not of concern with these tyre size changes. In fact, there is speedo error right out of the box with the Vitz/Yaris with OEM 14, 15, and 16 inch diameter wheels/tyres.

just a second , forgive me for my car ignorance but how can 15' inch wheels have different diameters like 23.4 and 23.7 ? (doesn't 15 = diameter )

and how about filling the tyre with nitrogen instead of air which is better ?

[ddongbap]

Its not the rims that make up different dia. Its the rubber size.

[thebarber]

nitrogen is a waste of money unless you track the car heavily

and cars have different rolling diameters and circumferences based on tire size.

205-55-15's are 205mm wide, the sidewall is 55% of the width (112.75mm) and the 15 is the wheel size. 195-55-15's are 195mm wide and the sidewall height is 55% of the width (107.25mm, in this case). 185-60-15's are 185mm wide, the width of the tire is 60% of the width (111mm) and the wheel is again a constant.

you want to land within 3% of your OEM rolling size to keep the speedo as accurate as possible...

1010tires.com had a great tire size calculator....
http://www.1010tires.com/TireSizeCalculator.asp

[b_hickman11]

just a second , forgive me for my car ignorance but how can 15' inch wheels have different diameters like 23.4 and 23.7 ? (doesn't 15 = diameter )

and how about filling the tyre with nitrogen instead of air which is better ?

Some tires can be the same size but have a different total diameter. It depends on the tread depth. Some tires come with a 9/32 tread depth while some others might have 10/32 or 11/32. Some may be even more than that.

[Russelt3hPirate]

Go for helium, but remember that it is highly explosive (remember the Hindenberg).

wasn't the Hindenberg filled with Hydrogen? :laughabove:

[Tamago]

wasn't the Hindenberg filled with Hydrogen? :laughabove:

i thought it was Centerlinium

[Russelt3hPirate]

i thought it was Centerlinium

if it was, it never would've broke/crashed

hahah

[Russelt3hPirate]

Some tires can be the same size but have a different total diameter. It depends on the tread depth. Some tires come with a 9/32 tread depth while some others might have 10/32 or 11/32. Some may be even more than that.

also depends on the width wheel mounted and actual section width which isn't always the advertised # on the sidewall. :)

[Tamago]

if it was, it never would've broke/crashed

hahah

germans or whoever built it should have had a conference call with some sort of Mechanical Engineer (09TRD!!!!!)

[JapRulezz]

ok ok , the site is great but there is one thing i dont understand
is the 205 more better than the 195 for me ?
isnt that much more rolling resistance even if it has 0.5 % less error of speedometer
thanx alllll