Back spacing again

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Oct 15, 2002
Ok I know it has been posted to death but I must ask. What is wrong with 3.25" back space, the track would be wider with the same size tire as compared to a 3.5" wheel
right? A 4" back space woud help keep larger tires under the fenders if tie rods and calipers clear, right?
So why be held to just 3.5 back spacing? Thanks for the help. JL ???
There is nothing wrong w/ backspacing of less than 3.5"... that's just the stock number. There are people running 2-2.5" and that's where my next set will be. Yes, shorter back space will likely add more stress to the lugs via the lever principle, but not enough that it matters to me. Also w/ a shorter backspace you could move the wheels out from under the fenders which some law enforcement groups don't like... but for the 1/4" you ask about your only question should be... "what do I prefer?"


oh yeah... and 4" backspacing can be a problem if you go to crossover steering... Scout conversions, etc.
15" rims will not fit with more than 3.5" BS. The rim will contact the steering arm. My 15x8 with 3.75" of BS contacted the steering arm until I installed .25" spacers. (I ordered 3.5" of BS, got missunderstood I guess) You shouldn't have any trouble out back with more than 3.5" of BS. With minitruck or stock manual steering too much BS will contact the relay rod-have heard of a cruiser with 16" rims, 4" BS and 12.5" wide tires contacting the relay rod.
when I bought my 40 it had 4" bs... wasn't a problem until I put the scount steering in... then the arm hit the tire not the wheel... so this may vary a bit truk to truk.
The 3 1/4" BS you ask about would hardly be noticeable. They'll fit fine. Less backspacing does widen track.
As for hitting the steering arms the stock arms allow for 3 1/2" BS. If you use highsteer arms that locate the tierod above and behind the axle the ackerman principle places the arm and TRE far from the wheel or tire. This will allow a deep BS wheel keeping the rubber under the fender. The negative aspect is that the tire now can rub the inner side of fenders during articulation.
Okay, how about opinions on 16" rims with 4" b.s., are there any problems with doing that? I figure that if a 15"er needs 3.5 b.s., then a 16"er should be good with a 4 b.s. Is there anyone out there that is/has tried this combo?

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