When I switch over to non-winter tires, I’m going to buy 4 cheap wheels to mount the new tires on. I could go 235/70/16 which is what I have now but some people prefer 235/65/17. I know what those numbers mean, but what is the difference in real driving/perfomance terms between 16" and 17" tires? They will be AT tires (I’m looking at Hankook Dynapro ATMs) with a fair amount of freeway and some unpaved roads but not (or very rarely) backcountry trails.
You really should check with a tire expert at a tire dealership. Different rim/tire size may affect handling characteristics. If you have an accident, an insurance company may deny payment since you modified the vehicle’s factory settings (any excuse, as you probably know).
You can change via the plus/minus one approach:
225/60-16 >>> 245/50-17 has the same rolling diameter, but better contact patch.
So… for you, if you have 235/70/16, you would go 215/60/17
You have some odd sizes, but might because you are using the winter size as the standard. What is the STOCK setup?
Dealerships and tire/wheel companies will refer to the “plus one” guide.
Stupid question time- wouldn’t changing rim size affect the odometer?
Argh!
I meant: 235/70/16 becomes 255/60/17
Diameter is, essentially, preserved and contact patch is improved. (No impact to diameter when overall tire height is maintained via a ‘plus one’ approach)
Handling should be crisper/faster. Car will react better to steering input. Will want to follow road grooves just a touch more.
Ride will suffer slighty. Less cushion, so bumps are a little sharper.
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Examples:
Original tire… Plus zero… Plus one… Plus two…
205/60R16… 225/55R16… 215/55R17… … 245/40R18…
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Only overall diameter, not rim size, will effect final drive ratio and odometer. W/regard to the difference between the two sizes you mention, the 70 series will provide a smoother ride at the expense of handling. The 65 series will provide the opposite. However, because the difference between the two is so minimal, it’s doubtful you would be able to tell one from the other. Theoretically, tire wear will be better with the 70 series.
So it sounds like on the Jeep (the car I’m doing this with) I should stick with stock size but for my SRT4, I may want to go +1.
Sure, it makes more sense to preserve the Jeep’s wheel/tire combo, but people do plus one them. If you were jumping to pure street tires, then maybe you’d go the plus route to give it a ‘street’ look.
On the SRT4, it does makes more sense to do a plus one or plus zero (has some nice benefits and you don’t need to buy wheels). Plus two is often pushing it; the ‘tuner’ crowd is usually the group that goes that far.
Remember to get wheels that have the same ‘offset’ when changing wheels. Hit me up if you don’t know what that is.
Excellent resource: www.tirerack.com
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I’m pretty sure 17’’ cost more for a reason I don’t know. Stick to the factory size for the best ride unless you want to go bigger for appearance reasons. You may save some money.
Er - because they are bigger?
Just in case Philster’s posts haven’t made things clear for everyone, generally speaking, when you increase the size of the wheel rim (from, say, 16" to 17"), you reduce the tyre profile (the “height” of the sidewall of the tyre) to compensate, so that the overall diameter remains the same. Otherwise, as has been pointed out, you will affect the speedometer, odometer, and handling of the car.
The previous posts have explained the basic effects of doing this.
Yeah but those damn 23’’ tires cost more than 24’’. 19’’ probably costs more than 20’’, and having worked at a used tire shop where the hardest size to come by were 17’’, I’d guess they are just an odd ball size.