Offset

[Jellybean]

Hi

 

Have 18" wheels and offset on sticker is 14.5 rears and 12 fronts

 

Does this sound correct?

[JamieP]

Not for a stock supra no, may work with overfenders.

[Jellybean]

Not for a stock supra no, may work with overfenders.

 

Mine is TRD widebody supra but they sit a few mm in

 

Does offset sound correct for my car application, plus they clear UK brakes

 

Just it has me confusted as measured the backspace to be 14.5 and the centerline to be 14.5 so I would imagine offset is 0 going by this logic but it says 14.5 on Sticker for front wheels

 

https://www.rsracing.com/tech-wheel.html

 

Measuring Wheel Offset

To calculate offset you'll need the following measurements:

 

Wheel backspace

Wheel Width

Wheel Center line (outboard flange to inboard flange measurement / 2)

 

Subtract:

 

Wheel center line from Wheel backspace to get offset. If backspace is less than the wheel centerline the offset is negative

If backspace is greater than the wheel centerline the offset is positive

Edited October 4, 2008 by Jellybean (see edit history)

[garethr]

Lay the wheel flat, face down.

Put a straightedge across it.

Measurement 1: The distance from the straightedge to the floor in mm divided by 2 (centre line)

Measurement 2: The distance from the straightedge to the mounting face (backspace)

 

The difference between the two measurements is the offset.

 

Still works if the tyre is fitted, but may not be dead accurate.

Edited October 4, 2008 by garethr (see edit history)

[Jellybean]

Lay the wheel flat, face down.

Put a straightedge across it.

Measurement 1: The distance from the straightedge to the floor in mm divided by 2 (centre line)

Measurement 2: The distance from the straightedge to the mounting face (backspace)

 

The difference between the two measurements is the offset.

 

Still works if the tyre is fitted, but may not be dead accurate.

REAR

Measurement 1: 28cm / 2 = 14cm

Measurement 2: 12

 

The difference = 2

 

FRONT

Measurement 1: 30cm / 2 = 15cm

Measurement 2: 11

 

The difference = 4

 

 

So how does 2 and 4 equate to something like19X9.5J ET+24

Edited October 4, 2008 by Jellybean (see edit history)

[garethr]

Are front and rear the right way round? You have the front (300mm) wider than the (rear 280mm).

 

On those measurements the 300mm wide wheel is ET-40 and the 280mm wide wheel is ET-20.

 

What does it actually say on the stickers? I think it would be unusual to measure offset to half a millimetre.

 

 

EDIT:

Just measured a stock Supra 9.5x17-inch rear (no tyre):

Measurement 1 - 270mm/2 = 135mm (centre line).

Measurement 2 - 185mm (backspace).

Difference is 50mm.

Backspace is greater than center line so offset is positive.

Offset = ET50.

 

ANOTHER EDIT:

I should have said that the wheel rim must be flush to the floor. On some wheels the centre sticks out further than the rim.

Edited October 5, 2008 by garethr (see edit history)

[Jellybean]

Are front and rear the right way round? You have the front (300mm) wider than the (rear 280mm).

 

On those measurements the 300mm wide wheel is ET-40 and the 280mm wide wheel is ET-20.

 

What does it actually say on the stickers? I think it would be unusual to measure offset to half a millimetre.

 

 

EDIT:

Just measured a stock Supra 9.5x17-inch rear (no tyre):

Measurement 1 - 270mm/2 = 135mm (centre line).

Measurement 2 - 185mm (backspace).

Difference is 50mm.

Backspace is greater than center line so offset is positive.

Offset = ET50.

 

ANOTHER EDIT:

I should have said that the wheel rim must be flush to the floor. On some wheels the centre sticks out further than the rim.

 

Sticker says 14.5 on the rear and is 12 or 12.5 on the front sticker

 

I must be doing something wrong measuring them myself