more pulling power
Senior User
Joined: Sep 2004
Posts: 352
Likes: 0
Originally Posted by handyman43358
The only question I have is what is the difference between tread width and tire section width?
"P225/50R16 91S
The 225 indicates this tire is 225 millimeters across from the widest point of its outer sidewall to the widest point of its inner sidewall when mounted and measured on a specified width wheel. This measurement is also referred to as the tire's section width. Because many people think of measurements in inches, the 225mm can be converted to inches by dividing the section width in millimeters by 25.4 (the number of millimeters per inch)."
tread width is what basically what it sounds like. it's the width of the portion of the trie that actually has the tread on it. the section width is basically tread width plus the bulge of the sidewall on either side.
Mike
Senior User
Joined: Sep 2005
Posts: 357
Likes: 1
Originally Posted by turbocoupe5.0
For example: 235/85R16
235 = tire section width (not actual tread width) in millimeters
85 = the aspect ratio in % (the height of the side wall is 85% of the section width
R (I believe the R means radial but I'm not sure)
16 = rim diameter in inches
235 = tire section width (not actual tread width) in millimeters
85 = the aspect ratio in % (the height of the side wall is 85% of the section width
R (I believe the R means radial but I'm not sure)
16 = rim diameter in inches
The old was makes so much more sense... today's americans are never going to convert to metric, just our scientists and engineers and mechanics who work on foreign cars. We have too big an ego and we wouldn't quite get it.
Senior User
Joined: Sep 2004
Posts: 352
Likes: 0
again, quoted from TireRack:
"P225/50R16, P225/50ZR16
The R in the P225/50R16 91S size identifies that the tire has a Radial construction in which the tire's body plies "radiate" out from the imaginary center of the wheel. Radial tires are by far the most popular type of tire today representing over 98% of all tires sold.
If the R in the size was replaced with a D (225/50D16), it would identify that the internal tire body plies crisscross on a Diagonal and that the tire has a "bias ply" construction. Tires using this construction are for light truck and spare tire applications.
If the R in the size was replaced with a B (225/50B16), it would identify that the tire body plies not only crisscross the tire on a diagonal as before, but that they are reinforced with belts under the tread area. This type of tire construction is called "Belted." Tires using this construction are practically extinct."
source: http://www.tirerack.com/tires/tirete...currentpage=45
Mike
"P225/50R16, P225/50ZR16
The R in the P225/50R16 91S size identifies that the tire has a Radial construction in which the tire's body plies "radiate" out from the imaginary center of the wheel. Radial tires are by far the most popular type of tire today representing over 98% of all tires sold.
If the R in the size was replaced with a D (225/50D16), it would identify that the internal tire body plies crisscross on a Diagonal and that the tire has a "bias ply" construction. Tires using this construction are for light truck and spare tire applications.
If the R in the size was replaced with a B (225/50B16), it would identify that the tire body plies not only crisscross the tire on a diagonal as before, but that they are reinforced with belts under the tread area. This type of tire construction is called "Belted." Tires using this construction are practically extinct."
source: http://www.tirerack.com/tires/tirete...currentpage=45
Mike
Senior User
Joined: Dec 2005
Posts: 206
Likes: 0
From: Piney Point Shores, Md
Originally Posted by turbocoupe5.0
Oh yeah, a larger diameter tire will act like a numerically lower gear like a 2.XX. A smaller diameter tire will act like a numerically higher gear like a 4.XX.
Higher Gear RATIO=Lower Gear
Lower Gear RATIO=Higher Gear
Taller tire=Taller gear, Smaller Tire=Smaller Gear.
Senior User
Joined: Aug 2005
Posts: 158
Likes: 1
I guess I wasn't as clear as I could have been on the metric/english conversion. Whiteyfordzx5 wrote it the way I meant it
And yeah, Spidk43, that is the most F'd up sizing system they possibly could have come up with. Years ago, when I tried to figure out what all those #'s on the sidewall really meant, I was like "What the F***?!, millimeters, %, and inches all in the same tire?, You've got to be kidding!". And, best of all, none of that tells you the tread width! I guess we shouldn't be surprized. All of us who wrench on fords from the 80's have been through the "is it inches or metric" hell. What I've learned on this one is 90% of the time, drivetrain is inches, suspension & body is metric. Of course, there are numerous exceptions to this. Oh well, that's my rant for the day
And yeah, Spidk43, that is the most F'd up sizing system they possibly could have come up with. Years ago, when I tried to figure out what all those #'s on the sidewall really meant, I was like "What the F***?!, millimeters, %, and inches all in the same tire?, You've got to be kidding!". And, best of all, none of that tells you the tread width! I guess we shouldn't be surprized. All of us who wrench on fords from the 80's have been through the "is it inches or metric" hell. What I've learned on this one is 90% of the time, drivetrain is inches, suspension & body is metric. Of course, there are numerous exceptions to this. Oh well, that's my rant for the day
Senior User
Joined: Sep 2005
Posts: 357
Likes: 1
I'm glad I got a standard/metric socket set for christmas this year (I'm 17, so there'll be plenty of time for wrenching more in depth, I've been borrowing my dad's tools and he doesn't have much metric stuff. I had to put a JAPANESE bike together for my sister for christmas, and I'll tell ya, Using metric sockets kicks using 2 adjustable wrenches clear outa the water!
What we've all learned from this, is that unless you're a math whiz, the best way to figure out tire sizes is to either A)carry a calculator at all times, or B) carry a measuring tape with you at all times (you can find the tread width that way too)
Of course, you could always memorize...
What we've all learned from this, is that unless you're a math whiz, the best way to figure out tire sizes is to either A)carry a calculator at all times, or B) carry a measuring tape with you at all times (you can find the tread width that way too
)Of course, you could always memorize...
