TIRE SIZE - OEM 18 WHEELS

[Larz]

I have stock 18 wheels on a RWD M35. I am considering going with a wider tire than the OEM 245/45/18.
When I say 'wider' I mean the surface that rides on the road. I have very little knowledge about matching tires to wheel size. I don't want to reduce the driving stability or safety and I'm wondering if anyone here has experience using a tire wider that OEM size on the 18 wheels. I believe the wheel size is 8.5 inches wide but not sure.
Any advise is greatly appreciated.

[CPJ LB]

hey Larz,

if your wheel size is 18 x 8.5 (not sure with offset) then you can try the following tires:

255/45/18
265/40/18

*should also work with 18x8 wheel size, but to be honest, I have never seen 265/40/18 used on fronts.

[Larz]

Hey CPJ,
Thanks for taking the time to help out. Your car is looking brilliant as always.
Cheers

[CPJ LB]

you're welcome Larz!! another thing that you may want to think about is just running spacers on your stock wheels...see how those feel prior to buying wider tires...unless you need new tires right away.

[finikM35]

When i bought my car i had 255/50/18 lol i used it for about a year no issues except it was a terrible tire - Nexen

[The Bodyguard]

hey Larz,

if your wheel size is 18 x 8.5 (not sure with offset) then you can try the following tires:

255/45/18
265/40/18

*should also work with 18x8 wheel size, but to be honest, I have never seen 265/40/18 used on fronts.

X2!!

[CPJ LB]

^Bodyguard!! what's up brotha!! how ya livin!! good to see you around here.....take care!!

[Larz]

Now that I have confirmed my wheels are 18 X 8, it seems best to stay with the 245/45. After teaching myself a bit about tires matching to wheels, I learned an 8" wheel is the absolute minimum width required for 255 and up - actually better suited for 8.5 - 9.5 inch wheels. I confirmed they WILL fit the 8 inch wheel .... but
I'm concerned that a 255 on my 8" wheel will cause a slight stretch and the weight of the car/wheel will be resting on a slight section of the innermost sidewall as well as the rib where the tire mounts. If that happens, physics tells me that will make the sidewall give more flex and be more wobbly when cornering. Possibly even reduce the actual surface area of the tread on the roadway too.
I'm going to stick with the 245/45's if I stay with my 18's or buy a set of 19 X 9's if I really want the 255's. I need to make up my mind by year's end so I have time to dilly about until then.
Thanks everyone for your input!