Rim and Ties sizes... What does it all mean?

[iownju]

Well this has been bugging me for a while, and i havent really done any research on it. But i was wondering, what the diferent numbers mean when buying a rim, and when fitting a tries on it. Also what are the rules for streching tires, and the sizes that go along with that??

was just curious, and thought id ask

[URMachines]

OK, well my explaining skills arent great but ill try and help you out.
to begin with tire sizing. lets say the tire is a basic 205/45/17
the "205" stands for how wide the tire is, in mm, accross the tread pattern. this size is about 8" wide.
the "45" is the height of the sidewall of the tire. but this is not a direct mearsurement. the number 45 actually stands for 45% of how wide the tire is (205). so if the tire is 205mm wide, then 45 % of that is about 92.25 mm. so that is how high the sidewall is.
the last number "17" is simply the size of the rim
so basically, a 235/45/17 sidewall will be bigger than a 205/45/17 sidewall cuz th ratio is larger ont the 235.

on to wheel offsets, its a lil more comlicated. i graph would be easier. but picture the centerline of a wheel from the side. now somwhere infront or behind that centerline, the hub will bolt to the wheel. say the hub mounting is +20mm infront of the centerline. that +20 is your offset. offset is used for fitment in the wheel well to clear suspension and fender walls.
hope this helps.

[Phoen_x]

Reading Tire Sizes:

Example Size: P205/60R-15OWL


P - Passenger

Tire sizes can also start with the following:

BP - Cosmetic Blemish Passenger

LT - Light Truck

205 - Width in millimeters of tire’s tread.

60 - Aspect Ratio - Percentage of tread width that equals the sidewall height.

R - Radial

The letter “R” can also include the following:

HR - H=Speed Rating

VR - V=Speed Rating

ZR - Z=Speed Rating

15 - Rim diameter in inches.



Other letter combinations include:

OWL - Outlined White Lettering

RWL - Raised White Letters

W - Whitewall

B - Blackwall

ORWL - Outlined Raised White Letters

WW - White Wall

BW - Black Wall


Tires can also be listed as:

205/60R-15 93H

93H - 93 Load Index, H Speed Rating

Light Truck (LT) sizes can include a letter at the end of the size.

LT265/75R-16/C

C - Load Range

Rule of thumb I've learned on Zilvia.net, when stretching tires, always or atleast go a 5 or Maybe 10 size smaller then the recommended for whatever size wheel you have. such as
instead of 225/45/17 use 215/45/17 or if your really crazy 205/45/17 (example looking down on the treads if the car was clear and measuring how wide it was from face of rim to back of rim (usually the first 3 numbers)

word of advice; google.com , make it your best friend in your case since you chose to use the sn, iownju.

[chmercer]

your stretching advice dosent really make much sense. plus 2 sizes down from regular baloon sidewall wont give you a good strech anyway. i say go about 50mm smaller width than regular. like on 10j grip people would run like 275. so get like 225/235.

[Craftsman]

MY question... What do you guys personally recommend? 17" rims or 15" rims?

The 17" would feel better when going sideways, but the 15" would accelerate like no tomarrow... So your thoughts...

Matt.

[Phoen_x]

Like on the last thread I replied Craftsman, it all depends on what car you have (wheel clearence) and what you plan on doing and your budget.

from what I've learned from what most 240'sx owners:
17x8/9 daily driving, drift it if you got enough power to carry you through it if not keep it as a daily driver and the money.

16's x8/9 Better for drifters practice/exhibition runs. Tires are pretty cheap for the size and wheels don't usually weight alot.

15's, more so if you plan on auto x or some type of track racing. Easier to accelearate for cars with not of alot of power. Of just wheels to slap on to ride on with cheap tires to the next event where you can switch em out.

[chmercer]

17s, smaller looks bad. if you are poor or have no power swap to SEs in the back for events.