So, I'm looking to buy some new tires in the next month or so. I bought my 07 last April and the tires are due for it. I looked at the tires currently on it and they seem to be 17s. So, I was wondering, is there a difference in using 17s or 18s? How do you make sure that the speedometer is accurate? Is one size more comfortable and more quiet? Any suggestions on a brand that people like for all season tires?

A lot of the threads I looked at are pretty old, so sorry for the new thread. Here is what I have now, sorry about the pic, it's the only one I have that shows the tires. It was after my wife blew a tire.

 

Those are OEM wheels, which suggests that they are 18 inch.

As for recommendations, that all depends on what your goals for the tires are. Any track use? Highway? wet/dry? Just a daily commuter?

Have you read the new and potential owners thread?

 

I'll have to check the size again. I live in Indiana so wet/dry and a daily driver.

 

I agree those look like the OE 18x8 50mm offset wheels.

The OE tire size is 225/45-18 which has an outer diameter of 26.0". Whatever tires you end up with, as long as they are within 3% of 26.0" (+/- about 3/4") then you'll be fine.
You can use this to calculate everything:
Tire size calculator

245/40-18 is probably the most common "+0" size for the RX-8.

As far as tire recommendations, we need more info.
You're in Indiana which means sub-freezing temperatures in the winter. Will you be driving this car during the winter? In snow?

If so, I recommend a set of dedicated winter tires on a spare set of rims. Nokian WRG3 are a good compromise between all-season durability and snow traction. Then you can run summer tires from March to November. For summer tires, I really like the Bridgestone Potenza S-04 Pole Position.

If you don't want dedicated winter tires but will be driving it in the cold, that rules out summer tires (unless you have a death wish, in which case just weld manhole covers to your hubs). The Continental ExtremeContact DWS is generally well-liked.

 

It's a daily commuter. We drive it in the winter but that's over so I don't need winter tires. It does rain a fair bit so I need something that's good in rain or shine.

 

Winter is over? I know Bloomington is a little warmer than where I'm at (Chicago) but I didn't think it was THAT much warmer. Also, you do realize that the seasons are cyclic, so it will be back again next December.

Anyway, if you're daily driving it regardless of weather, you'll probably want the Continental DWS because they are on closeout to make room for the new DWS 06.

 

Ya, when the cycle rolls around next year, I'll get snow tires. Worst case scenerio, I'll borrow my mother-in-laws 4x4