Aftermarket offset

ChiTownMaraud3r said:
I didn't determine backspacing. I'm using the value given on that info pic which has been around since forever to determine offset. Look at it again.

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Your confused on backspacing, and offset, the offset of a wheel will not change, only the backspacing can change by widening , or narrowing a wheel , determining backspacing has nothing to do with the offset of a wheel.
 
MOTOWN said:
Your confused on backspacing, and offset, the offset of a wheel will not change, only the backspacing can change by widening , or narrowing a wheel , determining backspacing has nothing to do with the offset of a wheel.
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I thought offset was measured from the center line of the wheel. If you widen the wheel to the inside (like people do to stock wheels) doesn't that change the centerline, and therefore the offset?
 
daddyusmaximus said:
I thought offset was measured from the center line of the wheel. If you widen the wheel to the inside (like people do to stock wheels) doesn't that change the centerline, and therefore the offset?
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No you cannot change the offset of a wheel , it is measured from the wheel center to the mounting surface.
 
MOTOWN said:
Your confused on backspacing, and offset, the offset of a wheel will not change, only the backspacing can change by widening , or narrowing a wheel , determining backspacing has nothing to do with the offset of a wheel.
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:shake: Negative. Not confused.. you're choosing to not think about it, otherwise you would have calculated the offset.

I'm not suggesting anything will change, which it will when widening but I'm only talking about the MM stock wheel which to date, nobody has ever posted a definitive offset from Ford, or a calculation on what the offset really is.

Once again,

We have 2 of the 3 values,
- Wheel width: (Outer to inner lip) we think this is 8" total.
- Backspacing: Mounting surface to inside lip edge(near shock) We think this is 6.295"
- Offset: Wheel center-line to mounting surface. Variable I was searching for.

Oh would you look at that, a relationship between backspacing and offset...They both share the same plane position, mounting surface. :shake:

Half the wheel width is your center-line and we know the backspacing(supposedly) so you can equate them by the mounting surface. Wheel width - backspacing = depth of the spoke(front wheel face to mounting surface)
4 - depth of spoke = offset.

MOTOWN said:
No you cannot change the offset of a wheel , it is measured from the wheel center to the mounting surface.
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This is some more of the bs I've been meaning to call folks out on when talking about widening wheels. You are adding material to one side of the wheel, of course the offset will change as it is calculated from the wheel's center line.

If my car wasn't in storage, I would just go out and measure the backspacing.
 
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ChiTownMaraud3r said:
:shake: Negative. Not confused.. you're choosing to not think about it, otherwise you would have calculated the offset.

I'm not suggesting anything will change, which it will when widening but I'm only talking about the MM stock wheel which to date, nobody has ever posted a definitive offset from Ford, or a calculation on what the offset really is.

Once again,

We have 2 of the 3 values,
- Wheel width: (Outer to inner lip) we think this is 8" total.
- Backspacing: Mounting surface to inside lip edge(near shock) We think this is 6.295"
- Offset: Wheel center-line to mounting surface. Variable I was searching for.

Oh would you look at that, a relationship between backspacing and offset...They both share the same plane position, mounting surface. :shake:

Half the wheel width is your center-line and we know the backspacing(supposedly) so you can equate them by the mounting surface. Wheel width - backspacing = depth of the spoke(front wheel face to inside face)
4 - depth of spoke = offset.



This is some more of the bs I've been meaning to call folks out on. You are adding material to one side of the wheel, of course the offset will change as it is calculated from the wheel's center line.

If my car wasn't in storage, I would just go out and measure the backspacing.
Click to expand...

Clearly you don't understand how an offset is determined , the wheel center to the mounting surface will never change no matter if you widen or narrow , thats not bs , its a fact.

The width of a wheel has nothing to do with backspacing , your not understanding how this works, you can argue it forever, it still will not change the facts.
 
ChiTownMaraud3r said:
I don't? LOL

I'm posting the calculations, you are saying incorrect without even looking at them, or offering a correct calculation. Beside's, there's plenty of wheel calculators which back up my math. This for example.
http://www.tyresizecalculator.com/tyre-wheel-calculators/wheel-offset-backspace-calculator

Sorry, your friend at welcraft just told you whatever to make the sale.
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Lmao! dude you have no clue as to what your attempting to argue about, if i don't know it to be fact i don't repeat it , but ok whatever.
 
MOTOWN said:
Lmao! dude you have no clue as to what your attempting to argue about, if i don't know it to be fact i don't repeat it , but ok whatever.
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You've provided 0 facts.

You're actually saying the wheel centerline to the mounting surface will never change. How is that possible if you are increasing the overall width of the wheel? Does the mounting surface change then because centerline does not change? The center-line is based on the width.

The only way the center-line does not change is if you add the same amount of material in front of the wheel face as well - causing a deep dish effect.
 
ChiTownMaraud3r said:
You've provided 0 facts.

You're actually saying the wheel centerline to the mounting surface will never change. How is that possible if you are increasing the overall width of the wheel? Does the mounting surface change then because centerline does not change? The center-line is based on the width.

The only way the center-line does not change is if you add the same amount of material in front of the wheel face - causing a deep dish effect.
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Son it's not my job to educate , and spoon feed you information ! If you truly want to know something learn it for yourself , then no one can tell you different.
 
MOTOWN said:
Son it's not my job to educate , and spoon feed you information ! If you truly want to know something learn it for yourself , then no one can tell you different.
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Exactly, and that's what I've done. Too bad other's can't do the same before posting "facts".

The entire reason I brought this up is because we don't have a definitive offset, some say 45 some say 50. I will get to measuring my stock wheels and post findings once and for all.
 
I don't get how an offset can't change when only adding material to one side of a centerline?

I would think back spacing and offset should would both be directly affected?

I guess I'm much more a finish Carpenter turned Plumber than a rim salesman because I compute some pretty serious calculations in my head all day at work LOL Unless this is just too simple?

Let's start with 5th grade.
10" rim / 0 offset / 5" back space

Adding 2" to the backside doesn't create 12" rim / +25mm offset / 7" back space?

Not stirring the pot. Just trying to solve a puzzle before bed. Yawn.




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justbob said:
I don't get how an offset can't change when only adding material to one side of a centerline?

I would think back spacing and offset should would both be directly affected?

I guess I'm much more a finish Carpenter turned Plumber than a rim salesman because I compute some pretty serious calculations in my head all day at work LOL Unless this is just too simple?

Let's start with 5th grade.
10" rim / 0 offset / 5" back space

Adding 2" to the backside doesn't create 12" rim / +25mm offset / 7" back space?

Not stirring the pot. Just trying to solve a puzzle before bed. Yawn.

Sent from my iThrone using Tapatalk
Click to expand...

Great. Someone willing to use their brain! Good man Bob.

If you only add 2 inches to the inside(behind the face of the wheel) you can imagine the wheel is growing outward 1 inch towards the front and equally 1 inch to the rear. This places the mounting surface 1 inch farther away from the original centerline. Your backspacing goes up by 2.

So yup, you end up with a wheel that is 12" wide with +25 offset and 7" backspace. It is easier visualized if drawn out.

If you add one inch in front of the face, and one inch behind the face, the offset would remain equal.

I wasn't trying to stir any pots, just tired of the he said, she said and as an Engineer, I want data to come to my own conclusions.
 
I thought I would add this picture for reference. The big problem with widening, as far as i'm aware...is any additional width they add, will only add to the backspace of the wheel (inboard of the hub surface).


trilogywheels.jpg
 
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