Gents,
I bought a set of 18" rims off an 04 Max. I did a search and got a lot of information about tires but not really sure my question was answered. The tire of choice for 18" rims seems to be a 235/40/18. All I'm trying to do is find a tire with the same width and height as the stockers (225/50/17). Will the 235/40 do that? After checking prices of 18" tires I amost regret getting these rims. There are a lot more choices in 17" and they are much cheaper.

Thanks

 

what are you wanting?

this is a tire size calculator so u can find what size is close to stock

http://www.miata.net/garage/tirecalc.html

 

You will probably get a lot of responses telling you that there is a Wheels and Tires forum. There will be a lot of good information for you there; however, before the flaming begins, let me do a quick breakdown of tire sizes for you.

235 = width of tread in millimeters
40 = % of width = heigth of sidewall (this is the aspect ratio)
18 = wheel diameter

To find a tire the same width as the original isn't as important as the same height (unless you've modified your suspension). I don't think you should regret getting the 18" wheels as long as you like the way they look on the car.

Personally, without a modified suspension, 17" is the largest wheel diameter that should be used on a 5th gen (and 5.5 gen) Maxima.

Getting back to the width of the tires, I don't think that you'll notice that big of a difference between the 235 and 225. Afterall, you're only looking at a difference in tread width of 10 millimeters (less than half an inch).

A quick formula for finding tire height is:
tread width
(multiplied by)
aspect ratio
(multiplied by)
2 [you have 2 sidewalls to account for]
(divided by)
25.4 [this will convert your measurements in millimeters to inches]
(plus)
wheel diameter
(equals)
tire height

225/50R17 = 25.858 inches
235/40R18 = 25.402 inches
235/45R18 = 26.327 inches

 

225/40/18 - Kumho Ecsta SPT's - you'll thank me later, trust me!

I'm about to replace a pair only because I have a problem with buying just one brand new tire. One became the victim of pot-holization and has worn beyond the point of saving it. Depending on how wide your wheels are will determine how wide of a tire you should get. Mine are 18"x8", so the 225 was best for me, but the tire calculator will get you the size you need so that it's as close to stock without affecting the speed sensor too much...

 

don't you think this size is too small comparing to stock?
I was thinking about getting 235/45/18 on a 18*8.5 rim

 

Dont get 45 for an 18 inch rim. Atleast on the front. I have 245/45/18 and my tires rub at full turn. I'm on stock suspension still. The rear is fine though. For 18s, a 40 would be perfect. Maybe even a 35 if your gonna be pretty low.

 

The ride is much better with 17's too, but 18's and 19's look better.

 

I'm on stock suspension as well and have had no problems with the 40, other than them damned potholes I hit and occasionally having to have foreign objects like screws and nails removed from them and have them properly repaired...

If my wheels were 8.5" wide, I would have probably gone with a 235 or maybe a 245, but what I have on there has resulted in a very smooth ride on the stock suspension for the most part, (which is what I wanted) and those tires have worn very well and perform better than the Dunlops that I originally had on those wheels when I got them. I'd say my Kumhos have about 70% life left on them after driving 60+mi/day for nearly a year and a half now. I will replace them with the same tires - no question.

 

I had to go with 245/45/18 to get a decent ride quality when I got 18s, no rubbing except rear passanger under lots of load . I'm dropped on progress springs too.

 

235/40/18.. on G's rims.. Falkens...

 

im thinking the same, its a little thicker sidewall than the 235/40, should be more comfy, tire calc shows it to be 0.5" thicker than the 235/40. I would love to go this size if it doesnt rub.

 

I went 245/40/18 - the wider the better, right?

If it doesn't snow in your area, I recommend general exclaim uhp's for tires. They are like $118 a piece at tirerack.com

 

245/40/18 is very close to 17" stock. once you've decided on a particular tire double check the specs to compare the outside diameter with stock. 225's are way to narrow and short for an 18x8 rim - at minimum go with 235/40/18 but 245/40/18 looks and performs great.

 

with going 245/40 would their be an issues with rubbing with a +30 offset and a 1.5" drop?

any reason you suggest 245/40 over 235/45 which is almost dead even to stock

 

You will be fine with 245/40/18s with 1.5" drop.

I say either 245/40/18 or 235/40/18, but prefer 245/40/18 for better ride quality.

 

i don't get any rubbing with my 245/40 and I'm dropped on progress springs

 

Rub depends on wheel offset and width.

245-40-18 or go home.

 

Nmex i got the same rims as you. 350z ouring rims +30 and +33 offset. I want to go 245/40, or 235/45 (preferably) but scared about rubbing with a little drop

 

bump to hotstartup's question, I want to get the 5 spoke 350Z wheels which are same offset and run 245/40/18 as well on Eibachs.

 

im riding on 04 18's also and just put on 245/45/18 which is the kind of meat i need on a tire in nyc...the only rubbing that occurs is in the rear when the enitre car dips into a pothole at a higher speed...i also have an xtremely heavy system in the trunk

 

i went with 235/40 i think its the safer way to go. tires should be coming soon.

 

Mine are 8.5" all around (+33). I only rub on very harsh bumps on only 1 side in the rear, AND I have 15mm spacers in the rear and 5mm in front.

 

So prior to the spacer absolutely no rubbing problems with 245/40?

 

what kind of tire can be fitted on 18x8.5 wheels?
I was thinking 225-235

 

there is a wheels/tires forum here for these kind of discussion....moving.

 

I wouldn't know since I've always had the spacers on.

IMO, 245 minimum.