Ok before i go ahead and order my new rims, I have been playing with the numbers and taking measurments to make sure they will fit.... So what im starting with: I have a toyota rearend, which is just about 2" narrower, and am converting the front to toyota spindles and hubs with tubular arms, NOW the rims im looking at are 20x8.5 with an offset of +25mm and a BS of 5.671 now taking into account my narrower axle and camber these should tuck right?? Any help would be great!!! thanks
Are you body dropped? Are you planning body dropping your truck? It does matter as the lower you go the less clearance you have as the mazda beds go inwards as you go up. Here is what I did to determine my backspacing/offset.
1)First figure out the overall diameter of your desired wheel/tire combo using the tire and wheel size calculator here...
2)Based on that decide how far the wheel is going to tuck up into the bed.
From that point hang a string and let it hang.This is the furthest point you want to stick out on your rim/tire. (obviously we do not want it to hit the inner side of your bed so we will compensate for that a little later)
3)Now from the base of your brake drum measure from the drum to the where the string is hanging. Now you know the distance from the mounting base of your wheel to where the very farthest front of the rim can be. (this is called front spacing)
Like this..
Now I know that this is pic of the front and he is only seeing what is needed to clear the fender opening lip but the same principle still applies...
4)So now you know you frontspacing, you can calculate you backspacing. Take the width of your wheel and and subtract the frontspacing number and that is your backspacing needed. Then add a quater inch to the backspacing to make sure that you don't hit the inner sides of your bed (Remember we talking about doing this earlier in step #2)
There you go!
Post was last edited on Jun 08, 2008 05:06. This post has been edited 1
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