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72NOVA454
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Help

When selecting tires, how do I know what "width" rim they will fit on?

Many tires might be listed like this example: P275-60-15

Many Rims miight be listed like this example: 15" X 8" with 4.5" backspacing.

So my question is, how do I know that a certain 15" tire like the one shown above will fit a certain rim like the one shown above?

For example, there are 15" rims that come in 4", 6", 7", 8" 10", 12" widths.
In that case, how do I know if the tire shown above (P275-60-15) will fit for example a 15" x 7" rim or a 15" X 10" rim?

I don't get it.

Lee
 

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A general rule is that the rim width should be about an inch less than the tread with of the tire.......so 275mm (10.8 in) should have a 9.8 in wide wheel.

I have 2 pairs of 275x15s...one on 10 in rims, one on 8 in rims....Both work fine
 

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In addition to the 1" general rule, many tire companies will post reccomended rim widths in their tire specifications.
Here is a sample page from the goodyear site. ( I just picked a random tire, goodyear has this info for all of their tires)
http://www.goodyeartires.com/goodye...eadwidth=&aspectratio=&rimdiameter=&sidewall=

I found that by browsing their catalog. Notice the column that says "measured rim width" . That is the rim they used to get the specific dimensions as listed. But you could mount that tire on any of the rim sizes they recommend, and you could taylor the tires performance by following the info you can find in this next link....


Yokhama has a page which explains rim selection in a little more detail.
http://www.yokohamatire.com/utwheels.asp

In there is says that generally you can select a rim that is 90% of the tread width, (not section width), and they give some more info regarding how a wider rim will make your car behave differently from a thinner rim..
Handy yokohama chart..
http://www.yokohamatire.com/utrimwidth.asp

Later,
Mikey
 

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I don't know if you need this, but here is a picture of a spiffy tool I made to check offsets and whether or not a tire will fit..

I cut a peice of plywood out to the width, height and section profile of a tire I want to fit to my car, then clamp it to a peice of square tubing that is bolted to the hub, making sure that the outside of the pattern is clamped to the tube so it matches the tire outside diameter. ( this particular plywood cutout is for a 12" wide tire, I made a few different widths and saved them as needed to use on different cars)

I can move the wooden profile in or out to clear the inner fender or beads and see the offset measured in inches. ( as you can see, I laid it out on the board)
Once I have moved the axle throughout it's range of motion, and spun the gauge aound and am satisfied there is enough clearance for the tire size I like, I can convert the offset measurement into a backspace measurement, based on the reccomended rim width for that tire. :)



Hope all that helps.

Mikey
 

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Bryan59EC said:
Too cool, Mikey

also looks like it could be made with something just laying about.

Bryan
What do you think I built it out of... :D


And yes Poncho, the picture of that spiffy rig is of it under the Chrysler Imperial,,,,,affectionately known hereabouts as ...THE BARGE!!

Crossing the channel may be part of its future. :D

Later, mikey
 

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72NOVA454
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Discussion Starter #8
you guys are the best - that's the info I need.

Now.............back to the garage to git er dun and figure out what to buy.

thanks.
 

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home brew said:
powerrodsmike - another great idea from the garlic capital!!! :thumbup: :thumbup: Those little jigs and "spiffy" tools you make are neat. Thank you for sharing. What ever happened to the Barge?
Thanks Homebrew :thumbup: The barge is chillin out in the parking lot, waiting for an influx of capital from it's owner, Gary. I'm still waiting for a box with the 14" front brake parts to be ordered as well.(2400.00 :pain: ). The last thing I did was pull out the motor and trans, swap the shockwaves for some mockup struts, and get the whole car steam cleaned. I made some adapters and modified a set of urethane bushings to hook up the K member a little bit stiffer.

The new motor is all done, the 700r4 trans and wilcap adapter still needs to be ordered.
I gave Gary the sizes of tires that would fit, and the rim backspacings and he is supposed to be buying that stuff also.

It just takes money to make our world go 'round

Later, mikey
 

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i was curious how much backspacing is usually ok before having to narrow my rear end. i have a 8 inch wide tire now and i have approx 19 inchs from the front of the rim to my frame which would allow me 8 more inchs allowing 2 inchs for tire expansion now if my rim has a 4 inch back space adding 8 more inchs would create 12 inchs of backspace and only four in front is that a issue?
 

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The rim won't care, but you are going to have to find a manufacturer that will make a rim the size you need with that backspacing.

A quick search on the Weld wwheel website showed me that they have a 15 x 15 inch wheel with 7.5" of backspacing.

http://www.weldwheels.com/wheels/de...e&style=90&desc=1-Piece Forged Alloy Polished


I don't know what size wheels or style you want, so you will need to check around. It starts getting complicated when not all sizes are offered by all manufacturer of tires, and if you want big rears and small fronts and want them to match in tread pattern...

I'd start to familiarize yourself with the tire catalogs and the wheel manufactuers and find one you like.. I know that some of them will build you a wheel to your specs, (within reason), but they are not cheap. :pain:

I know that weld and billet specialties will make a wheel to your specs. Check the size availability for the style you like and see if they have that wheel available in an 8" backspacing.

Later, mikey
 
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