are the sidewalls on 215/45 and 235/45 the same?

 

no

profile is % of width

215/45= 96.75mm sidewall

235/45 =105.75mm sidewall

width * profile=sidewall..

thats why 225/40 255/35 and 285/30 have same sidewall

 

can you answer this for me. right now i have 225/40/18's in the front and i am rubbing pretty badly. can you suggest something for me cause i already changed my springs once already didnt do much. My question is if i go with a 225/35/18 would that make a difference of not rubbing?\

And what is the difference in size from a 40 to a 35 sidewall?

 

thanks

 

Your problem is more the width of the tire than the height. More info on rim width and offset may get a better answer, but switching to a 215 tire will help a lot more than running a smaller sidewall. Also when you start messing with different sidewall heights your ABS may not work correctly. Changing sidewall height will change your speedo in the rear as well. Rolling your fenders and adding negative camber will help with rubbing as well. You can't get much of a roll out of the front but it will help a little. A 215 tire will be your best bet if you are rubbing alot unless your offset is low 40 and below.



Difference in size will depend on tire width. As was stated already the second number (ie 40 or 35) is a percent of the tire width so (225 x 40%) minus (225 x 35%) will give you the difference.

 

DerrS2K is on the money. You probably will be better off with the 215/45R17 on the front and a 245/40R17 on the rear. If it looks like the 215/45R17 is going to rub you can go narrower with the 205/50R17 without giving up any height.
If I can help let me know.

 

well i have 18x8 in the front and 18x9.5 in the rear. My problem i dont think is the width of the tire because i'm getting rubbing from the top of the tire pretty much, its not actually the sidewall. I know i would be better off with 17's but i have my rims already and i changed springs twice already. I first used eibach but that lowered the car too much, so now i changed it to swift springs which made it alittle better.

So i just want suggestions but putting more negative camber sounds like my best option right now

How much camber would be good do you think?

 

If you are rubbing from the top it sounds like you are too low. Negative camber will not fix that because it will tilt the tire in and up.

Like this --> //.

If by the top you mean the inner lining attached to the lip mainly that screw that holds the fender lining up at the lip, your problem is still wheel width and not height. (negative camber could help this problem)