17x7 vs 17x7.5 and tires (noob questions)

[toki]

Ok I am going to be needing some new tires and rims here probably in like 6 months, but I want to get looking and just keep a lookout and know what I want now. Now the rims I want only come in 17x7, but I will be needing atleast a 225/xx/xx for my tires with my SR running the basic mods making 240rwhp to start, but more later with more upgrades and all that. And all the tire sizes I see for these rims are 205/xx/xx. I know jack about tires, so can you put 225/xx/xx or even 245/xx/xx tires on 17x7 rims, or should I just look for 17x17.5s ? Thank in advance.

[Exar-Kun]

the widest you'd want to go on a 17x7 would be a 225mm wide tire, and its plenty wide for 90% of the uses out there(its what I use, but I have a 7.5" rim) the extra .5" will allow you to run a 235 width tire safely, such as a 235-40-17. both sizes are a bit too high for the stock tire combo(overall diamterer of the rolling assembly will be larger) so it will effectively hurt your low-end gearing....but not by much.

in short, if you like the 17x7 and its offset is decent for the mods you plan, just buy that and get a 215-40-17 or 225-40-17(nitto and falken make these) possibly and be happy -chet

[AZhitman]

Chet - Actually, 245 is fine on a 7" rim. (I'm running 255's, but that's really pushing it.)

But I agree with your point about diametr, esp for the 240sx. 225/40/17 on a 17x7" rim is a nice upgrade.

[MainEvent212]

u run 255's on a 7" rim !?!?!?! omg...i didnt know that was possible...

ur tires must be bulging like hell

[Exar-Kun]

a 245-50 on a 7" may be fine, but not a 245-40....the sidewall wouldnt have enough give to make the bead seat properly. either way, the smallest listed rim width for a 245-40-17 is a 7.5", but if you look at any tire, the higher the sidewall, the lower the rim width required(like the fact a 265-75-16 is approved for a skinny 6.5" rim)



anyways, keeping the O.D. close to stock is the way to go, unless you have both the knowledge and ability to calculate the exact ratio you want in every gear and manipulate it all to your liking(most of us don't)-chet

[AZhitman]

True, true. I hadn't considered the sidewall aspect ratio issue.

maine, my tires look fine - See Member's Rides.

If you come up against a curb and your rim is the first thing to touch it, your tires are too damn skinny IMO.

[Exar-Kun]

If you come up against a curb and your rim is the first thing to touch it, your tires are too damn skinny IMO.

hahaha. get a rim protector!

hoser!-chet

[AZhitman]

"Rim protector"? What's that?

I just meant that the current "trend" toward an overall "convex" rim face vs. concave is ridiculous. I can parallel park with both sidewalls touching the curb without worrying about chewing up the lip of my rim....

[Exar-Kun]

rim protector=a tire with a rim protection flange.

haha. got some fatty 16" tires huh AZ?-chet

[AZhitman]

255/50zr16 directionals.... with a rim protection flange molded into the sidewall... :oface

[Grant@tirerack]

Quite a few of the newer performance tires have a recessed sidewall where the bead and sidewall meet. It dog legs in so there is a nice notch where the wheel lip sits and sometimes even a small ridge of extra sidewall rubber to protect the wheel.