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Offsets on 18" wheels

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Old Jun 12, 2006 | 09:11 PM
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Default Offsets on 18" wheels

I have a 1980, and I'd like to place Foose 18 x 10 wheels on the rear. The front will get 17x8. My question is does anyone know how much negative offset I can use in the rear. I would like to avoid the zero offset on the rim, and would like to have 4 inches on the outside of the rim, and six inches on the inside. I believe this would put the front and rear tires tracking the same on the outside. Any thoughts would be appreciated. Thanks
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Old Jun 12, 2006 | 09:34 PM
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i think u would need offset trailing arms for a 10" wide rim with that much offset

i have 20x9" with 0 offset and 4.5 backspacing


b
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Old Jun 13, 2006 | 05:43 AM
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I am running 17X8 with a 4 inch offset in the front. 18X10 with a 5.5 offset in the rear. I have the stock trailing arms with the Ebrake cable relocated. I have no rubbing issues and everything tucks inside the wheel wells. 255 45 17s front and 275 40 18s rear.
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Old Jun 13, 2006 | 10:43 AM
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i too am running the 18x10's in the rear with 5.5" bs. i recently replaced the stock ta's with offset ta's... both will work but with stock arms, you have a tire size limit if you want to keep it tucked fairly in the wells and not contact the arms. with 6" bs the tire may contact the frame. i can only stick my finger in between the front of the tire and frame to give you an idea. in most cases, you will loose the rear swaybar and also need a shorter / custom rear spring.
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Old Jun 13, 2006 | 10:57 AM
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The 5.5 offset you refer to is a 5.5 backspacing. Is that correct? I just need to try and get fairly large tires in the rear since the motor I am placing in the car is around 475 hp. Thanks
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Old Jun 13, 2006 | 11:14 AM
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Originally Posted by attyman1968
The 5.5 offset you refer to is a 5.5 backspacing. Is that correct? I just need to try and get fairly large tires in the rear since the motor I am placing in the car is around 475 hp. Thanks
Gordonm and i are running the same rear wheel / tire combo. yes, 5.5" backspacing.
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Old Jun 13, 2006 | 11:14 AM
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Can't you go to a speed shop or a tire shop where you are thinking about purchasing the wheels, jack the car up, and test fit a rim with different offset?? You are spending alot of money so get it right.
I am lucky in the fact that the speed shop lets me take anything home. I did use a 10 x 18 wheel with 5 inch backspacing as one of the measuring wheels.
I ended up ordering custom 10 x 18 with 6.5 inches of backspacing but again my car is highly modified to accept this backspacing.
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Old Jun 13, 2006 | 01:06 PM
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Originally Posted by Gordonm
I am running 17X8 with a 4 inch offset in the front. 18X10 with a 5.5 offset in the rear. I have the stock trailing arms with the Ebrake cable relocated. I have no rubbing issues and everything tucks inside the wheel wells. 255 45 17s front and 275 40 18s rear.
Gordom, are you running a sway bar ?? And do your tires stay inside of the wheel wells ?? Are those TT2's ??
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Old Jun 13, 2006 | 01:10 PM
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5.5" max backspacing.
6" and the tires will rub on the frame in front. trust me I know...
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Old Jun 13, 2006 | 02:52 PM
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Originally Posted by jimmygmartin
Gordom, are you running a sway bar ?? And do your tires stay inside of the wheel wells ?? Are those TT2's ??

No rear sway bar. A 420 lb rear spring that has been shortened 1 inch both sides. The tires are inside the wheel wells. Yes they are TTIIs. You have to custom order 18X10 with a 5.5 backspace.
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Old Jun 13, 2006 | 06:24 PM
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hmmmm

i figured i'd get it wrong....hehe

b
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