Tire width vs aspect ratio

[Harry6]

I have an opportunity to switch tires / rims on my car at no cost. I am wondering if the switch would be likely to cause a fuel economy penalty. The replacements would be either of two possible sizes, I don't yet know which. I'll know the size before I decide whether or not to switch.

On one hand, the replacement tires would be wider the stock tires, and that would likely be bad for FE.

On the other hand, the replacement tires have a larger diameter, which would be good, and lower aspect ratio, which I suspect would also be good. Care to venture a guess about the likely outcome?

The car is a camry, current, stock, tires are 205 65 R15, outside diameter is 25.5 inches.

Option A is 215 60 R16 (10mm wider then stock, slightly lower profile, outside diameter is .6 inches more then stock.

Option B is 215 55 R17 (10 mm wider then stock, lower aspect ration then stock, outside diameter is .8 inches more then stock.

Incidently, I notice that current Camrys, including the hybrid, use the 215 60 r16 size. Of course, this could just be for styling, and the gear ratios could have changed as well.

What do you think?

Harry

[Daox]

I'd stay with the stock tires.

[hummingbird]

If at all, go for skinnier tyres. The thicker ones will do you no good.
Aspect ratio and dia will not be any effective - their contribution, if any will be very small in practice.

[NeilBlanchard]

Hiya Harry,

You CANNOT put 17" tires on 16" rims! (Or, do you have the option of using 17" rims?) Whatever size you get, you may want to look for the Michelin models with the "Green-X" tag -- these should have lower rolling resistance than others. And I'd go stock or narrower, and check the odometer for accuracy after you have them installed.

[tasdrouille]

Stay with stock size. If you'd have said 205/60R16 with steel wheels or 215/70R16 (for highway use) that would have been different, but that's not the case with the options provided. Avoid alloy wheels, ventilation resistance is bad.