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Old 07-30-2007, 10:08 PM   #1
Jcentsr6
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-6 offset?

http://www.67-72chevytrucks.com/vboa...d.php?t=179881

check this out...I love this truck set-up, Still thinking about the tire size, but I do love the look...anyways I checked the specs on those wheels and

18x8.5 (f) 4.5bs
20X10 (r) 5.25bs

Well I found some wheels that are very close in specs (without custom making them) and the only thing is the Offset for the wheel im looking at says -6? ? How will that work out...does anyone have that set-up or close on their trucks?

ALSO: Sorry for the questions....I want to spend the $$ one time..not two Thanks
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Old 07-30-2007, 11:24 PM   #2
SactoJim
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Re: -6 offset?

Offset and Backspacing are two diff things.

-6 should be 6mm offset from centerline of wheel. This basically means that the mounting surface of the wheel is 6 mm (inboard) from the centerline of the wheel. (+) offset would be the other way.
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Old 07-31-2007, 07:25 AM   #3
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Re: -6 offset?

Is -6 offset wheels okay?
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Old 07-31-2007, 10:59 AM   #4
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Re: -6 offset?

6mm translates to 39/64".....real close to 5/8". The wheel mounting pad is 5/8" (inboard) of wheel centerline (negative offset). On a 10" wheel, that translates to 4 3/8" back spacing (back spacing is measured from back rim bead to the mounting pad). On a 8" wheel, you're looking at 3 3/8" BS with a -6mm offset.

I would say that those wheels would work as long as you don't intend to substantially lower your truck or use bags.

The wheel specs that you mentioned from the truck you like have a positive offset and bring the wheel and tire's more inboard, giving you more clearance when the truck is lower.
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Old 07-31-2007, 11:37 AM   #5
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Re: -6 offset?

Actually 25.4 mm = 1 inch.

25.4/6 = .236" or 15/64. A little less than 1/4"

4.5 bs on 8.5 is about +12.5mm
5.25 bs on 10 is about +6.25mm

Whether they will work or not I don't know. I have 10s with 5 bs on front and back and have no problem on a stock height truck. I've had the rear on the bumps and still no problem.
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Old 07-31-2007, 01:16 PM   #6
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Re: -6 offset?

COOL. I guess we will find out, I just ordered 5 lug performance disc brake set-up, rear axles, and full wheel package (foose nitrous). I have the air ride tech cool ride system...need to install it. So I hope everything works out...just spent $6k on everything...it better fit.
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Old 07-31-2007, 01:36 PM   #7
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Re: -6 offset?

Quote:
Originally Posted by SactoJim View Post
6mm translates to 39/64".....real close to 5/8". The wheel mounting pad is 5/8" (inboard) of wheel centerline (negative offset). On a 10" wheel, that translates to 4 3/8" back spacing (back spacing is measured from back rim bead to the mounting pad). On a 8" wheel, you're looking at 3 3/8" BS with a -6mm offset.

I would say that those wheels would work as long as you don't intend to substantially lower your truck or use bags.

The wheel specs that you mentioned from the truck you like have a positive offset and bring the wheel and tire's more inboard, giving you more clearance when the truck is lower.

How do you know that the other truck's wheels mave a pos offset? I dont plan on a c-notch or anything....but I am going to install airbags before the wheels are installed. Do you think I have serious problems? ? I ordered 255/50/18 and 295/45/20 (slightly lower sidewall than the other truck.
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Old 07-31-2007, 02:04 PM   #8
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Re: -6 offset?

I don't have a bagged truck so I'm not absolutely sure what is the best offsets/backspacing to use, but the lower you go with your truck, the more you will have to "tuck" you wheels in to avoid clearance issues with your inner fenders.

Seems to me that the guys that are "slamming" these trucks have to have a positive offset wheel.......think of it like this...The more positive the offset, the less "deep" the wheel looks.

I know the wheels you mentioned have a positive offset because the backspacing #'s are bigger than half the overall width of the wheels.

You need a "bag" guy to chime in on whether or not your wheels will work or not.
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Old 07-31-2007, 09:02 PM   #9
lowdowndirtyshame67
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Re: -6 offset?

I have been waiting to see the foose nitrous on a truck that year! You have to send me pics when they are on! I have put Nitrous wheels on all kinds of cars, but no trucks...I can't wait to see them!
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Old 07-31-2007, 10:14 PM   #10
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Re: -6 offset?

I want to see pics with the Foose wheels also!!

Please post them as soon as you get em on.

I am considering a similar setup.

Thanks
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Old 07-31-2007, 11:16 PM   #11
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Re: -6 offset?

will do guys....I am excited to say the least! I will post pics as everything comes together.
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