I just bought a used 07 G35x. It has Eagle RS-A's on it. The car has 47k miles on it but the tires seem to be in decent shape, so they're probably the second set on the car but still probably stock size. I'm not all the impressed with them and when they start wearing I'd like to put something different on. I'll research the type of tire since the car will rarely be in snow, normally used as a work-and-back car but sometimes for some sporty stuff.

What I'm wondering is what is the largest tire you can put on the stock 17" rim? I'm assuming the O.D. needs to stay the same but maybe there is something wider? Also, this is an 'x' (awd) model. Not sure how that affects tire selection. I'm assuming as long as they're all the same O.D. then its okay.

Thanks for any assistance or first hand experience.

George

 

Hard to say, each manufacturer has a recommended width rating for their tires. I suggest looking for the tire you want, then checking their specs to see how wide you can go.

A couple things to note, however:
- Better tire compound on narrower tires will outperform poor compound on wider tires.
- You can only go so wide on a particular wheel width, generally there's not much to be gained between, say, a 225 and a 245 if your wheel width is the same. The contact patch will barely improve. Most people think their tires have more contact because the bulge on the sidewall makes it look wider.

That said, the RS-A is an all-season tire. Any summer tire will likely outperform it even if you keep the same size.

 

That makes sense. I like the look of a wider tire but if it doesn't increase the contact patch by much and might even introduce more sidewall flex I probably ought to stick with the stock size.

I suppose I could go to an 18" rim and maybe a slightly wider tire.

So I guess the next question is a good rim and tire size for this car to improve general handling without worsening the gas mileage?

 

Yep, the Goodyear RS-As are a horrendous tire match for this car, much more suited to an Accord/Camry w/ 230hp, definately not up to the Gs 328 ponies. I put 20s w/ 243/35/20 Dunlop Sport Signatures and have been very happy w/ the much improved handling and connection to the road. The rims weighed about 1.8 lbs more than the stock 17s and the wider tires are a bit heavier~this resulted in about 1.5-2 mpg worse than the stockers but a very good tradeoff IMO. Road noise didn't increase much at all either, and it looks SOOO much better. The 245/35/20s are the EXACT same diameter as the stock 17" RSAs too, so no ABS/Traction control issues.

 

stock wheels are 17x7

largest width will be 225 or 235, but thats pushing it.

 

The stock RS-A's are 225.

blnewt, don't those 20 inch rims and very narrow sidewalls make the ride rougher? I'm not put off by a slightly harsher ride, but I don't want it to be a buckboard.

As far as looks go, I think the stock 17" rims are very nice. But they do look too small and this car, even though it is very sleek and sexy, needs a little more aggression and bigger rims would look nicer. May have to step up to some 18s or 19s but I'm trying to resist spending a bunch of money on mods for this car. I've been down that road before and wasted a bunch of money. But it is hard to resist.

 

We had an 07 G w/ the 18" sport wheels and the 20s don't really ride much rougher at all. If you hit a pothole or something rather significant you definately will feel the jolt more than you would w/ 17's or 18's but other than that, on regular roads I don't notice any unpleasant harshness. I like
19s also but the tires are quite a bit more expensive. If I had to do it all over I'd do the same thing, and I'm just storing the stock 17s & RS-As and will put the 20s on our next G (if they improve the crappy paint that is )

 

Do the 20's require any suspension mods or spacers? Is the offset different from stock?

George

 

No mods on mine, I bought tires/wheels at www.Tirerack.com and when you enter the vehicle/model/year it'll give you optional rim sizes w/ factory offsets so they'll bolt right on and fit perfectly. If you search my posts I've got some pics, no time for me to link it right now