Wheel Question

**Hemi31** · 12-01-2005, 09:02 PM

I found a set of wheels I really like but they only come in 18"x8 with a 4.5" backspace.Since I have no idea how to convert CM to inches,will this fit my Mag?

**Netsrac** · 12-01-2005, 09:06 PM

4.5 " = 11.43 cm

1" = 2.54cm

No I'm not that smart have a conversion calculator

**done** · 12-01-2005, 09:59 PM

Originally Posted by Hemi31

I found a set of wheels I really like but they only come in 18"x8 with a 4.5" backspace.Since I have no idea how to convert CM to inches,will this fit my Mag?

Yes that is a 14mm offset, so they will fit.

**VanillaRT4me** · 12-01-2005, 10:46 PM

Originally Posted by Hemi31

I found a set of wheels I really like but they only come in 18"x8 with a 4.5" backspace.Since I have no idea how to convert CM to inches,will this fit my Mag?

Hemi31, Is the bolt pattern 5-115? You'll want to make sure of that before you purchase these wheels too.

**Hemi31** · 12-01-2005, 11:35 PM

They are 114.3.I'll get the rings and they will be fine.Anybody remember the old Magnum 500 wheels from the Chargers and 70's Road Runners.I found these in Billet and 18x8.

**deuceroadster2** · 12-02-2005, 12:10 AM

Hemi31:

I would be surprised if they work. That is an old style RWD wheel which is not what our Magnums run. Don't get backspace confused with offset, they are not the same.

**VanillaRT4me** · 12-02-2005, 02:46 AM

Originally Posted by done

Yes that is a 14mm offset, so they will fit.

Here's a link to a chart that converts backspacing to offset.

http://www.rsracing.com/tech-wheel.html#backspace

Look up the 8" width wheel with 4.5" backspacing and the offset is zero. The minimum offset we need for our cars is 10mm.

So, no, these wheels will not fit.

**Hemi31** · 12-02-2005, 08:42 AM

Nuts!

**done** · 12-02-2005, 08:51 AM

Originally Posted by VanillaRT4me

Here's a link to a chart that converts backspacing to offset.

http://www.rsracing.com/tech-wheel.html#backspace

Look up the 8" width wheel with 4.5" backspacing and the offset is zero. The minimum offset we need for our cars is 10mm.

So, no, these wheels will not fit.

Their chart is wrong. From their page, the definition of offset.

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

The centerline is 4" so 4.5 offset is greater by 1/2" or 14 mm.

**nyxis** · 12-02-2005, 11:27 AM

Originally Posted by done

Their chart is wrong. From their page, the definition of offset.

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

The centerline is 4" so 4.5 offset is greater by 1/2" or 14 mm.

wheel width is to the inside of the wheel lip... centerline goes to the outside of the lip..

so the total wheel with outside to outside is 9" .. backspacing is 4.5" .. inside wheel width is still 8" ..