Tire question

zevo · 02-21-05, 10:03

My car has 225/50/17 on front and 235/50/17 on back and I am considering 225/45/17's all the way around for winter tires, and I think this would be fine as the difference in sidewall height and width is minimal. Does anyone disagree?

The wheels are 7.5" front and 8" rear

O4cobra · 02-21-05, 10:05

You would be fine.

White95Max · 02-21-05, 10:07

I agree...you won't have any problems with that.

bet993 · 02-22-05, 08:01

Depends on what you consider minimal. The circumference difference of the of the rears is 4 inches less and the diameter is 1.3 inches less with the winter tires. If your speedometer reads from the rears your speed will read 4.9% to fast (i.e speed reads 60 you will be doing 57.1). This will also increase the number of miles on the odometer faster than the actual miles driven. The front differences are approximately 2.7 less on the circumference and .9 inches less on the diameter. The speed difference is 3.4% to fast (i.e. speedo reads 60 you really are going 57.9). Again the odometer will read more miles than what is driven. Check out http://www.miata.net/garage/tirecalc.html to compare aspect ratios.

Also realize to that by changing the tire sizes to something other than what the manufacturer specified can effect the way the car handles. On some cares this can make a significant difference and on others the effect is negligible.

Accumulator · 02-22-05, 10:16

I might go with 225/50/17 snows instead. Besides being a closer match size-wise, I'd much rather have more sidewall when driving in winter conditions.

I'd also mount them on dedicated winter wheels.

Actually, I'd get the most narrow, high-profile setup I could that would still be close to the original diameter and still clear the brakes/etc.

bet993 · 02-22-05, 11:05

I agree with Accumulator. Drop down a size (to 16" form 17") if possible and keep the same aspect ratios as the OEM tires in that size reduced size.

I have done this on both of our cars. Both of our cars had "upgraded" wheels. I purchased used factory standard wheels and got dedicated snows that matched the standard factory sizes

Ben Z. · 02-22-05, 12:06

I agree, no need for 225s or 17s. Plus I bet you can get a narrower set mounted on a set of smaller wheels for about what the 17" tires alone would cost.

Kind of late to be buying winter tires?

Lowejackson · 02-22-05, 12:26

Quote:

Originally posted by Accumulator
I'd also mount them on dedicated winter wheels.

Winter wheels? How or why are they different to normal wheels

andriver · 02-22-05, 12:30

Quote:

Originally posted by Lowejackson
Winter wheels? How or why are they different to normal wheels

No different other than for the ease of changing them at the start of the winter season.

Lowejackson · 02-22-05, 12:31

Thanks

Accumulator · 02-22-05, 01:06

Quote:

Originally posted by andriver
..[winter wheels are] No different other than for the ease of changing them at the start of the winter season.

Plus I get ones that are both easy to clean and as sturdy as possible. Winter is *not* the time of year for BBS-style wheels or uncoated aluminum ones

and with all the potholes we get I decided to run steelies on the minivan in the winter.

Remember to make sure the lug nuts/bolts for any second set of wheels will work on your spare (I have to carry OE lugs for one of our cars just for the spare).

zevo · 02-22-05, 05:51

The reason for the size I listed earlier is that they are lightly used and cheap. My thoughts were to use my stock 17 inch wheels for the snow tires and buy 18's for the summer. I drive one mile to work and the rest of the time we use my wife's SUV.