2 replies to this topic

[Lima31]

I'm trying to get the front wheel offset on a standard LH confirmed for once and all.

 

Ignoring L34 as it is apparently -6.35mm (-1/4") (http://holdenpaedia....m/Stud_Patterns) due to the different caliper / steering arrangement

 

For the rest of the square bodies, unmolested steering and brakes, Gregory's manual says +28mm.

 

This thread cites +19mm and 28mm and different depending on rim size

http://www.gmh-toran...fset-confusion/

 

This thread also cites different values depending on wheel size

http://www.gmh-toran...rana-commodore/

 

 

So which is it

 

And is the offset (measured between centreline of wheel and hub face) apparently different depending on rim size? Does this mean if we replace with say a 17x8 even if the rolling diameter is maintained (~600mm??), will 19mm offset no longer be correct geometry?

Edited by Lima31, 07 November 2013 - 12:17 AM.

[76lxhatch]

Using the same offset on a different width wheel will maintain exactly the same track width. So yes, it is the same measurement. If your replacement wheel and tyre is also exactly the same rolling diameter then you will also maintain the same scrub radius.

But, that doesn't necessarily mean that for a different width wheel you want to maintain the same offset. I would be very surprised if the wider ones weren't (deliberately) a slightly different offset to make best use of them. For example if you used a taller tyre at the same offset this would decrease the scrub radius, so you could instead run a wider offset and keep the same scrub radius. Clearance is often a consideration too.

[Growla]

I went 4.5" bs on 17x8 and 5" on 17x9.5 bs to keep the track width within the 25mm tolerance you are allowed to play with when I changed my wheels. So 8" has a zero offset and the 9.5 have 1/4" offset. I hope this helps.

 

cheers

 

Mark

Edited by Growla, 11 November 2013 - 09:31 AM.