Tire guys help me.

[Z-owned]

I don't know much when it comes to tire's but I have some 17" 350z wheels on my car and need to get some proper size tires, currently I have 225/50 front and 235/50 rear and the sidewall is way to much. i believe the fronts are 7.5" and the rears are 8" I am wondering what is the widest i could go on them is and if i should do 40 or 45 for sidewall.

[ashibah83]

225 would be pretty square on the front, and 235 would be square on the rear, a 225/45 would be would be 1 inch shorter than the 225/50, a 225/40 would be 1.8 inches shorter, but VERY few tire manufactures make a 225/40

a 235/45 would be woud be 1 inch shorter than a 235/50 and a 235/40 would be 1.9 inches shorter

here use this, http://www.miata.net/garage/tirecalc.html

[Z-owned]

Thanks I have called a few tire shops around and have been told I can run a 235/45/17 in front and a 255/40/17 in rear. Does that sound right to everyone or should I stick to a 245/40 in the rear?

[simmode1]

^^^ You could do that, but I wouldn't. I like meaty tires as much as the next guy, but thats going to be over-square and give you that doughboy tire look, which is not sexy.

I'd go with 215/50 & 225/50 to keep to your orginal diameter stock, but 45 profiles will look better if you don't mind your speedo being off a little...

[Z-owned]

my speedo is off with the 50 series I have currently since those sizes are meant for the 350. Stock wheels on my car were 16" which ran 225/50 so with the 17's i believe I need a 40 or 45 max to keep the speedo semi accurate. Your right as well i don't want my tires to be bulging over.