WELD WHEEL QUESTION on backspacing- your advice

[Spenc2u]

Interested in the new WELD Pro Star XP's ( although they're brutally expensive)..

my question is ... what would be the correct backspacing to use with my current Rear Tire size 'if' I stay with a 16" rim. ( Tire now 255/50/16) I want the most dish I can have in the rim as possible

is it 5.5? or 4.5? Not sure what the backspacing is on my current ROH ZR6 16x8 rims, but with 255/50/16's I'm rubbing the outer lip of the fender enough I have to get them rolled.

if I go to a 15" rim, I'll go 275/50/15's minimum.. love the look of 295/50/15's


The WELD Pro Star XP link - http://www.weldracing.com/ProStarXP.html


Hope this makes 'some' sense

Thanks
Spenc