Dartman1967
Well-Known Member
Will someone PLEASE explain backspacing and if/when I need to consider it. I want to get new wheel but have no idea if they will fit my 67 dart, etc. Thank you in advance
Backspacing confusion
- Thread starter Dartman1967
- Start date
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philllyc
First time restoration guy
I hope this is what you mean. Wheels can be purchased nowadays where the distance from the outer rim to the inner hub is different. This enables the vehicle to use wider tires without cutting the quarters or offsetting the leaf springs inward. However the dimensions are critical. Remember measure twice cut once.! I made the mistake of cutting my quarters 40 years ago...DUH... I hope this is what you are asking about. when in doubt GOOGLE it.. Good Luck
TrailBeast
AKA Mopars4us on Youtube
Example:
My wheels are 4.5 backspace and I have a gap between the tires and the quarter panel of 1 inch, and a gap between the tires and leaf springs of a half inch.
If I wanted wider tires I would have to get a 4 inch backspace to move the rim and tire a half inch farther out so they would fit in the opening without hitting the springs or the fenders.
My wheels are 4.5 backspace and I have a gap between the tires and the quarter panel of 1 inch, and a gap between the tires and leaf springs of a half inch.
If I wanted wider tires I would have to get a 4 inch backspace to move the rim and tire a half inch farther out so they would fit in the opening without hitting the springs or the fenders.
dano
Evil Handy Man
Tell us about your 67. Is it all sock, been converted to large bolt pattern, or updated to something like an Alterkation. These will all change your offset (backspacing).
player1up
Well-Known Member
Backspace is the distance from the mating surface ( part that touches the rotor stud face ) to the furthest inner part of the wheel lip ( where the wheel weight mounts on older wheels ) .
Backspace is a static measurement in relation to rim width.
For example:
A 17x9 inch wheel with 4.5 inch backspace has the same backspace as a 17x8 inch wheel with 4.5 inch backspace BUT the 17x9 has a 1 inch wider outer lip.
Offset is the distance of the mating surface in relation to the center line of the wheel. Negative offset is toward the inside of the wheel and positive offset is toward theoutside of the wheel.
Offset in how it relates to backspace will depend on wheel width* ( unless offset is 0 )
For example: fyi offset is usually expressed in mm not inches
17x9 inch wheel with -25 offset will have a backspace of 3.5 inches.
17x8 inch wheel with -25 offset will have a backspace of 3 inches
Google offset vs backspace to see a bazillion pics of the description above.
Backspace is a static measurement in relation to rim width.
For example:
A 17x9 inch wheel with 4.5 inch backspace has the same backspace as a 17x8 inch wheel with 4.5 inch backspace BUT the 17x9 has a 1 inch wider outer lip.
Offset is the distance of the mating surface in relation to the center line of the wheel. Negative offset is toward the inside of the wheel and positive offset is toward theoutside of the wheel.
Offset in how it relates to backspace will depend on wheel width* ( unless offset is 0 )
For example: fyi offset is usually expressed in mm not inches
17x9 inch wheel with -25 offset will have a backspace of 3.5 inches.
17x8 inch wheel with -25 offset will have a backspace of 3 inches
Google offset vs backspace to see a bazillion pics of the description above.
Dartman1967
Well-Known Member
Thanks for the explanation guys....I think I got it.....It has not been modified that I know of. I am finishing it for my late son. He left a list of things that he wanted to have done and I am trying to finish it....wish I was a gearhead and knew something about these things. Thanks to this forum I am getting somewhat of an education..
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