Dropped C10 15x10 Rear Wheel Backspacing

[fxrsrider]

'75 C10 w/5" drop and rear wheel disc brakes

After looking at all of the past posts on wheel backspacing, I can't find a clear answer as to what backspace measurement will fit my particular application.  I'm looking for a set of vintage racing mags to run as my rear wheels.  Correct me if I'm wrong, but I'm thinking that if I can get the wheel dimensions right, then I can choose a tire that will work with my 5" drop.

I want to run 15x10's as my rear wheels.  My rear end is a 12bolt.  I recently replaced the rear drums with four piston Wilwood disc brakes.

Can anyone suggest what backspacing measurement or range of measurements will work for me?

4.0" BS seems to be an agreed measurement on previous posts.
4.0"-4.5" BS seems to be an agreed measurement range that will also work.

Is 3.75" BS acceptable too?  What about 4.75"?

Thank you in advance for your help, advice, and suggestions.

[fxrsrider]

[Irish_Alley]

wish i could give you some sort of insight but i have no ideal about a drop. i know others do so keep looking up they will be on here sooner or later

[fxrsrider]

cool.  Thank you Irish!  I ran across a set of vintage American Racing magnesium wheels w/ a 3.75 backspace.....which is why I'm a bit eager to figure this out.

I suppose I can just measure.....am I missing anything (below)?

[RAD77C10]

fxrsrider, I believe you'll find that might be to must front spacing, unless you have a narrow side wall tire, like 10" across side wall!  If it rubs the wheel well, you could trim it alittle, but might work!

[fxrsrider]

fxrsrider, I believe you'll find that might be to must front spacing, unless you have a narrow side wall tire, like 10" across side wall!  If it rubs the wheel well, you could trim it alittle, but might work!

thank you for the advice, RAD. I was thinking that might be the case with the 3.75".  It's hard to find a good set of original Mags....so when these came around, I was hoping they'd fit.  For the price, I'm going to pass and wait for the right pair....not interested in trimming the fender at all.

I suppose 4.25" BS would be the sweet spot for a 15x10?

[RAD77C10]

Right on!

[NASTY-LSX]

Yes, for a 15x10 4 to 4 1/4 Bs would be perfect.