Tire size help
 

For a few months i've been wanting to get new wheels. I know that the ones i have now are robbing my fuel economy. The tires are 205/50/17 with a 17x7.5 rim. I always thought they were lighter, but in actuality, they are the same weight as my winter wheels :eek:.

I know that winter's fast approaching, but can't wait any longer. Found a decent set of 15x6 steel rims for relatively cheap that i could buy. Of course, i would be looking for skinnier tires. The car originally came with 195/65/15. I have 2 choices, stay with that size or get 185/65/15.

The only problem that i see with the 185/65/15's is that they would throw off the speedometer by about 2%, which means if the speedo says 60 MPH, would really be going 58.8 MPH.

What tire size would u guys go with?

As long as the tires are going to give you the traction you need year-round I wouldn't worry about the speedo being 2% positive...the best balance of winter grip and economy is probably the way to go. Plenty of guys on here run tires that throws their speedo off. I'd be more concerned with the effectiveness/economy of the tires vs. the math of the speedo.

Don't use the 185/65R15's:

1) That would be going down in load carrying capacity and that increases the risk of a load related tire failure, which sometimes has tragic results.

2) There is probably a very slight RR penalty for using small tires.

Capri is right about load, but I wouldn't say you shouldn't do it. My stock tires are 195/65R15 and I got 185/65R15's for the winter. I did pay attention to the lower load capacity, but it was within limits. I hauled quite a few things on them and had no problems. When I'll need to replace my summer tires they'll also be 185/65R15's, no doubt about it.

So my advice is to first check whether the weight limits will be OK, and if so then go for some skinny low RR's :)