Wanted to know what is the widest tire we can run on OEM 18 coupe wheels and be safe. I know some guys run a 275, but I think that is not recommended for the oem wheels.

Anyone have wider tires than the stock 245 in the rear and please post pictures.

thanks.

 

i believe the widest tires you can run on the OEM 18s are 245 40 for the front and 245 45 for the rear...

 

stock is the above listed sizes but if you look the shoulders of the tires are rolled a bit. I have on 2 coupes replaces the tires with 245 front and 265 rear. the shoulders a almost square with the increase and as long as you don't use junk tires it sticks a bit better

 

+1.

 

yea I would think with a 8" up front you could fit a 245, and with 9" in the back a 265 would be doable. thats prolly what Im gonna do with my stockers, 245,45,18 and 265 40 18 in the back, would this be a even aspect ratio for the height of the tires?

 

the 18" rear wheels are 8", NOT 9". 245 is the widest tire you should run on them

 

so the stock rims are not 18x8 and 18x9 hmmmmm someone lied to me...
so what are the width differences on the front and rear rims then...?

 

there is no width difference, they are 18x8 all around on the coupe, only the tires are staggered

 

search for the miata tire size comparison calculator page to find up and down size comparisons to make sure you're looking fo the correct sidewall aspect. as for 245 being the widest recommended for the rear, i've read that as well but installed 265 anyway and had no negative effects. I used Michelin PS2s on both cars if it makes a difference

 

Correct me if I'm wrong, but wouldn't a wider tire look weird since you'll have more rubber sticking out the sides? I also hear this causes more sidewall flex which will make your handling suffer. I've seen people go thinner tires to get that super sporty low profile stretched look, but don't know why you would go wider.

 

with ps2 265 the tread doesn't stick out. look at the stock tires and they're rolled on the shoulders almost like something drifters use. if you change the width and sidewall ratio correctly th sidewall height is changed by maybe 1-2mm. you can change the sizes and keep the speed rating under 1mph difference at 60mph. or just go the easy way and run 245s all around the car

 

good info in this thread, thanks guys

 

im runnning 255/45/18's in the rear, nitto invo's and 225/45/18 in the front

and thats because a local shop ordered the wrong tires for me and i was like eff it. first and last time.

 

I'm guessing 275's gotta look pretty somewhat swollen and bulgy on the sides.

 

agreed for that