Newbie Question

[Derrickjr]

Hello everyone,

My name is Derrick Jr., and I am a new member from California looking for some guidance.

I need help understanding wheel fitment specifications. Previously, I have only worked with the ET63 offset typically found on OEM Porsche wheels. Now, I need clarification on how a backspacing measurement, specifically 7 5/8 inches, relates to those figures.

More specifically, my vehicle can accommodate an 11-inch wide rim with an offset (ET) in the range of 60mm to 63mm. I am trying to determine if an 11-inch rim with a backspacing of 7 5/8 inches falls within that acceptable range.

Any insights you could provide would be greatly appreciated.

Thanks in advance.

Derrick Jr.

[Trak Ratt]

Hello everyone,

My name is Derrick Jr., and I am a new member from California looking for some guidance.

I need help understanding wheel fitment specifications. Previously, I have only worked with the ET63 offset typically found on OEM Porsche wheels. Now, I need clarification on how a backspacing measurement, specifically 7 5/8 inches, relates to those figures.

More specifically, my vehicle can accommodate an 11-inch wide rim with an offset (ET) in the range of 60mm to 63mm. I am trying to determine if an 11-inch rim with a backspacing of 7 5/8 inches falls within that acceptable range.

Any insights you could provide would be greatly appreciated.

Thanks in advance.

Derrick Jr.
Welcome but you might list the vehicle. Many here have played the figment game and can help, but the vehicle type, model and year help.

[BlackTalon]

That ET is about 2-1/2 inches. so for an 11 inch rim that would be an 8-1/2 inch backspacing.

[Dandelion]

FWIW, the offset is how far off the centerline the HUB of the wheel is, while the backspacing is the space behind the SPOKES. The two measurements are separate and not directly relatable, as the spoke shape varies.

ed

[Trak Ratt]

That ET is about 2-1/2 inches. so for an 11 inch rim that would be an 8-1/2 inch backspacing.

https://www.tirerack.com/images/techCenter/wheels/offset_diagram.gif

[rothaus]

Try this. You can enter wheel and tire size and see ET (off-set) etc.

https://www.wheel-size.com/calc/

Cheers
Engelbert