Jump to content
HybridZ

rim backspacing/offset question


Recommended Posts

To start i have some rims on my 78 280 that are 15x7 0 mm offset 4 inch backspacing .

 

The rims i want are 15x10 -45 mm offset and 3 11/16th backspacing . I cant move the rim any closer towards the struts then what the 15x7s are now . I read a site about off set and backspacing the way i understood it because of the 0 mm off set compared to the -45 mm offset that the 15x10s will be closer to the struts .

 

The web site with the rims had me a bit confused if the 15x10s have less back spacing the the 15x7s doesnt that mean that the wider rims will move away from the strut , but the way they worded the offset setting it seemed like it would move closer to the strut ?

 

So would the 15x10s work for me ? Im running a 295/50/15 tire now with about 1/8the clearance between the strut and the rubber hence my concern on the rim not moving inwards .

 

Thanks for the advice/help with my question

Jason

Link to comment
Share on other sites

Backspacing is exactly what it says - the distance from the edge of the rim to the back of the hub mounting surface.

 

Offset is either positive or negative if you have any. The thing you haveto keep in mind with offset is that you have to realise that the wheel is actually a full inch wider than stated specs when figuring out backspacing.

 

Positive offset will move the hub surface toward the outside edge of the wheel and negative toward the inside edge.

 

In your case, with 15x7 wheels, which are 8" across - you have 0 offset and a backspacing of 4 inches - see how what I said works out?

 

15x10 wheels woould actually be 11" wide, so with 0 offset would have a backspacing of 5.5", but you have a negative offset (which moves the hub mounting surface toward the inner rim of the wheel of 45mm, which is a little over 1.75" and you wind up with 3 and 111/16" backspacing - which will fit strutwise, but not in stock fenders

Link to comment
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

×
×
  • Create New...