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Some of the larger size tires on tirerack are actually less expensive than my stock size. Would increasing the overall diameter of my tires by around an inch be dangerous? Would it likely touch any of the suspension components?

These are the sizes I'm looking at:

From:
205/55/16 (sidewall height of 113)

To:
205/60/16 (sidewall height of 123)
215/55/16 (sidewall height of 118)
215/60/16 (sidewall height of 129)
225/55/16 (sidewall height of 124)

The feedback I get here will help me narrow down what I can and cannot get.

:)

The feedback I get here will help me narrow down what I can and cannot get. :)

Yikes! You're going to rely on semi-anonymous suggestions on the internet to determine the wheel well, brake and suspension clearances of an unidentified car?

Anytime you increase tire outside diameter and/or widths you are getting closer to hitting stuff. You're also changing the gearing, odometer and spedometer accuracy.

And you're doing this because bigger tires are cheaper??

From what I've read, it seems as if larger tires get better MPG due to higher load ratings which leads to less deflection. Also better handling.

Also, changing the gearing should mean that at highway speed RPMs are lower.

The change in odometer and speedometer readings I don't really care about.

Plus they're $20 bucks cheaper a tire. I think that's reason enough, but please feel free to try and change my mind, because I'm a car noob and I don't know much about this stuff.

Without knowing the make/model of the car, it is impossible to even guess whether you have any chance of larger tires fitting. To save $20 a tire, you risk damaging the tires (or the fenders or fender liners) if the car cannot accomodate the greater diameter.

If you are concerned about spending an additional $80 on a set of four tires, you should be concerned about the possibility of losing one or both front tires to damage due to contact with fixed parts of the car's undercarriage. Having to buy another set in the correct size makes the $80 savings seem like a false economy. You may get away with it, you may not. It depends on the car.

Search the web for tire size calculators. Here's one I've been using for years. http://www.miata.net/garage/tirecalc.html Theoretically, a 225 50 r16 would be the same total diameter as your OE 205 55 r16. What's important is to keep the overall diameter and revs/mile the same between the OE and the new size. It's the same concept as plus sizing if you were going up in rim diameter. The only difference is you are just trying to tweak the width and profile to avoid more expensive tires. As others have stated here, the OE size would be ideal, but if you were to change wheel sizes look at the following things.
- Current clearances of the tires at normal and full wheel lock in both directions with a full load in the vehicle. You'll want to see how much room you have to work with.
- Measure the section width of the mounted OE tire and use that as a reference when looking at new tires. You'll find the mounted width for every tire in the detailed specs page with a certain reference wheel width. For example, the OE Dunlop SP31 for a Civic Hybrid is 7.9" wide at the widest part of the sidewall when mounted on a 6" rim. Compare the numbers on the tire you want to buy with the OE reference to find the delta and determine for yourself if sufficient clearance exists.
- Measure the total diameter or look it up online for the OE tire. Then go into the detailed specs to find the diameter for the new tire. Keep the overall diameters close and the speedo will be fine.

Spend some time researching online at performance car forums and you'll find plenty of tips on tire selection. Obviously, the OE size is safe and simple but you can deviate within reason. My van runs OE 225-60-17 and I put on 235-55-17 tires from my Mustang GT and ran those tires for 30K + with no issues. The tires ran 1 mph slow on the highway but that was the only downside. I've since replaced them with Avid TRZ's at the OE size though.