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sailsmen
08-14-2005, 06:32 PM
What is the offset on an OEM wheel?

Waht is the offset on a Lidio widened OEM wheel?
BK_GrandMarquis
08-14-2005, 07:12 PM
What is the offset on an OEM wheel?

Waht is the offset on a Lidio widened OEM wheel?

The offset should be 50. I don't believe what Lidio does changes that. He just cuts into it and welds an inch and a half to it. This probably makes the inside rim closer to the car components. I think this is why some guys got the QA1 shocks to make more room for the 305 tires.
TooManyFords
08-15-2005, 04:50 AM
The offset should be 50. I don't believe what Lidio does changes that. He just cuts into it and welds an inch and a half to it. This probably makes the inside rim closer to the car components. I think this is why some guys got the QA1 shocks to make more room for the 305 tires.Bzzzzzt! Oh, we are so sorry. We do have some lovely parting gifts for you. Thanks for playing!

:)

But seriously, when Lidio adds 1.5 inches (38.1 mm) to the back side of the rim, the offset is changed to 88.1mm. Offset is a function of rim width, not of factory specifications. If you wanted to find a rim with identical specs as the widened rims, make sure you look for a 9.5" wide rim with an 88mm offset.

Huzzah!

John
BK_GrandMarquis
08-15-2005, 07:04 AM
Bzzzzzt! Oh, we are so sorry. We do have some lovely parting gifts for you. Thanks for playing!

:)

:bigcry: :bigcry: :bigcry:

I don't get partial credit for the OEM offset and 1.5 inch?
This is why I don't play online games. Parting gifts suck. :P

Oh well, I knew someone would chime in with the correct answer. ;)
GarageMahal
08-15-2005, 07:31 AM
Bzzzzzt! Oh, we are so sorry. We do have some lovely parting gifts for you. Thanks for playing!

:)

But seriously, when Lidio adds 1.5 inches (38.1 mm) to the back side of the rim, the offset is changed to 88.1mm. Offset is a function of rim width, not of factory specifications. If you wanted to find a rim with identical specs as the widened rims, make sure you look for a 9.5" wide rim with an 88mm offset.

Huzzah!

John

Actually, isn't offset measured from the centerline of the wheel? So wouldn't adding 38mm to the width would only add 19mm to the offset?

jta
TooManyFords
08-15-2005, 08:04 AM
Yep, I just replied to the PM from BK and realized my error there. I forgot to divide it by 2 before adding to the original offset. 69mm is the correct offset for Lidio's widen rims.


Ding, Ding, Ding!

You're into the bonus round GarageMahal!

:wink:

Huzzah!

John
AzMarauder
08-15-2005, 08:06 PM
Actually, isn't offset measured from the centerline of the wheel? So wouldn't adding 38mm to the width would only add 19mm to the offset?

jta
I will chime in here and make a fool of myself... why not.... I'm flying tomorrow to MVIII so I won't matter ! :D

I thought offset was measured from the mating surface (where the rim bolts to the axle) to the edge of the rim.

Thus if you widen the rim... but all the "width" is added behind the mating surface then you wouldn't be dividing it in 1/2 would you?

Example.. using rough figures... if a rim has 5" behind the mating surface... ( isn't this called 5" backspace) and you add 1.5" behind the mating surface... you come up with 6.5" total behind the mating surface.... no division is required.
NRAUD
08-17-2005, 05:53 PM
Actually, I think that "offset" is the relationship between the centerline of the rim, and the mounting surface of the rim. "Zero offset" would have the mounting surface at the centerline. As the mounting surface moves outboard from the centerline of the rim, it becomes "positive offset". If it moves inboard of the centerline, it becomes "negative offset". I think AZMarauder has it right in reference to the backspacing, which would be the distance from the mounting surface to the inboard lip of the rim.
STLR FN
08-17-2005, 06:40 PM
This should clarify:

http://wheeltool.com/info/offset.html
SergntMac
08-17-2005, 07:35 PM
I thought offset was measured from the mating surface (where the rim bolts to the axle) to the edge of the rim. There's a big difference between what "wheel", "rim", and "hub" mean to us. That said, you are correct, your statement is true.

"Offset" is the distance from the point where the wheel meets the axle (our mounting pad) to the center line of the wheel. Therefore, "Lidio wheels" add more wheel width to the back, and from that point, "offset" (as it's measured backwards) changes, as it has been explained here. However, what does not change, is the distance between the outside of the wheel and the MM fender lip.

A 50mm offset wheel will still place the outer edge of the wheel (and appropriately sized tire) at a specific distance from the MM fender lip. This will not change when a "Lidio widened" wheel is in place.
TooManyFords
08-17-2005, 08:40 PM
A 50mm offset wheel will still place the outer edge of the wheel (and appropriately sized tire) at a specific distance from the MM fender lip. This will not change when a "Lidio widened" wheel is in place.
Yes, it does change. The physical position from the mounting surface to the fender lip does not change but the offset is no longer 50mm. It is then a 69mm offset wheel when you widen it Lidio style.

Offset is a function of rim width centerline, not backspacing. You widen the rim, you change the centerline. If you change the centerline and do not add equally to each side of the mounting surface, then the offset WILL change. Make sense?

Good!

Huzzah!

John