Backspace and offset measuring

[BR3W CITY]

I'm trying go figure out what I need to run in the rear of my truck. Right now its got a 12bolt rear end, setup 5x5 pattern. I'm tubbing my bed and I'm trying to figure out the best rim and tire combo to stuff into there, and to do so I need to calculate the backspacing and offset I need to make it all look right.

I'm at an 15x8 right now, and I'd like to move up to a 15x12 most likely, or possibly only a 15x10 if I I can get the width on the tire instead of the rim (if that makes sense). Anyone have the tool they sell for this? I've tried some of the regular tape measure methods but I get different numbers each time depending on the instructions i get. I plan on finding some steel 5x5 steel wheels to widen if I can get the calcs done correctly the first time.

[WickedSix]

well for one I would either use backspacing OR offset...my preference is backspacing because you have an easier definition of the inner rims lip to the mounting face...versus offset where you are measuring the offset of the mounting face from the midpoint of the rim width

depending on how you like the look of your 15x8 will determine where you put the additional rim width... but more important is the tread width and the section width of the tire you plan to run as these will define the outermost areas for potential contact with the body or the frame

[BR3W CITY]

que?


How can I know what tire I'm going to run, until I know what wheels I'm getting? Or am I missing something?

I can visualize in my head what I mean, but I can't visualize what you mean. I've seen the charts and stuff, but certain dimensions I can't even take with the truck on the ground, because the big fenders block access.

[Haulin' Oates]

Try this; http://www.carcraft.com/techarticles/ccrp_0610_muscle_car_performance_wheels_fitment/sway_bars.html