what OFFSET
09-06-2008, 12:47 AM
#1
JK Enthusiast
Thread Starter
what OFFSET
i hate backspacing
what offset do i need a 9.5 to clear a 305/65/18
i ahve a set of 18x9.5 +23 after a 25mm adapter spacer to make it 5x114.3 will it work?
what offset do i need a 9.5 to clear a 305/65/18
i ahve a set of 18x9.5 +23 after a 25mm adapter spacer to make it 5x114.3 will it work?
09-06-2008, 02:20 AM
#2
JK Super Freak
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I think our bolt pattern is 5x127.
I'm not really sure of the backspacing to offset formula.
That's like a 34x12" tire so I'm gonna say 4.5" backspacing and guess...
Screw it... I looked it up...
To find a wheel’s offset:
* First, measure the wheel’s backspace
* Measure the wheel’s overall width from outside rim edge to outside rim edge
* Divide the wheel width figure by 2
* Subtract the resulting figure from the Backspace measurement
I'm not really sure of the backspacing to offset formula.
That's like a 34x12" tire so I'm gonna say 4.5" backspacing and guess...
Screw it... I looked it up...
To find a wheel’s offset:
* First, measure the wheel’s backspace
* Measure the wheel’s overall width from outside rim edge to outside rim edge
* Divide the wheel width figure by 2
* Subtract the resulting figure from the Backspace measurement
09-06-2008, 02:22 AM
#3
JK Enthusiast
Thread Starter
spidertrax makes a 5x5 to 5x4.5 adapter
i want to use these wheels off my drift car
i know what the offset is. i just cant comprehend the whole backspacing to offset conversion
i want to use these wheels off my drift car
i know what the offset is. i just cant comprehend the whole backspacing to offset conversion
09-06-2008, 03:23 PM
#4
JK Super Freak
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Does this help? Found this somewhere else...
TO CONVERT OFFSET TO BACKSPACING:
For positive offset wheels: (Wheel Width +1)/2 + (offset * .03937)
For negative offset wheels: (Wheel Width +1)/2 - (offset * .03937)
TO CONVERT BACKSPACING TO OFFSET:
Backspacing – (Wheel Width + 1)/2 * 25.4 = offset
Round this result to the nearest milimeter. If the answer is a negative number the wheel has negative offset, if positive then a positive offset.
TO CONVERT OFFSET TO BACKSPACING:
For positive offset wheels: (Wheel Width +1)/2 + (offset * .03937)
For negative offset wheels: (Wheel Width +1)/2 - (offset * .03937)
TO CONVERT BACKSPACING TO OFFSET:
Backspacing – (Wheel Width + 1)/2 * 25.4 = offset
Round this result to the nearest milimeter. If the answer is a negative number the wheel has negative offset, if positive then a positive offset.
09-06-2008, 04:00 PM
#5
JK Super Freak
LOL
You may hate it..but, that doesn't change that you need it.
Kind of along the lines of me hating not having enough mod money...
...it doesn't make me not need it.
Since you have the rims...just MEASURE the BS, and you WILL KNOW what it is.
1. Lay the rim on the floor, brake side up.
2. Lay a straight edge across the top of the open end.
3. Stick a ruler along the straight edge down to the hub mounting face of the rim.
4. Read off of the ruler to get how many inches from the hub face to the straight edge...that's the BS.
To clear a 305 mm section width tire, you want less than or equal to about 4.75 - 5.0" of BS.
The width of the rim doesn't change your clearance...only the BS does.
So - see what your ACTUAL BS is...
...and for every inch of spacer and/or adapter thickness you add, you are subtracting an inch of BS, etc.
Hope that helps!
You may hate it..but, that doesn't change that you need it.
Kind of along the lines of me hating not having enough mod money...
...it doesn't make me not need it.
Since you have the rims...just MEASURE the BS, and you WILL KNOW what it is.
1. Lay the rim on the floor, brake side up.
2. Lay a straight edge across the top of the open end.
3. Stick a ruler along the straight edge down to the hub mounting face of the rim.
4. Read off of the ruler to get how many inches from the hub face to the straight edge...that's the BS.
To clear a 305 mm section width tire, you want less than or equal to about 4.75 - 5.0" of BS.
The width of the rim doesn't change your clearance...only the BS does.
So - see what your ACTUAL BS is...
...and for every inch of spacer and/or adapter thickness you add, you are subtracting an inch of BS, etc.
Hope that helps!
