Interesting observation on fitting tires

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Was going through some photos and these two are interesting. The first is with the spring removed and the axle jacked up to the bump stop. 3" of clearance. The opposite tire is sitting on the drive, a little bit up from normal ride height. The second photo is of the same wheel opening- at least at the top, the rear wasn't bent over yet, same bumpstop, only in this photo, the tire is almost touching the opening. The difference is the opposite tire is at full extension - 14" shocks maxed and J-springs unseated an inch or two. From the first photo I was thinking fitting 42's would be easy. The second shows the 37's barely fitting. Didn't think the articulation would cause that much difference, but it does make sense. That also explains why when I looked at the DS it had more than 3" of clearance, cause it had the axle sitting completely level.

So, I guess the moral is, if you put really long travel shocks on, the added extension can have a negative effect on fitting tires. This would explain somewhat where I've seen others on 37's (like Nay) who have more clearance than I do - 10" shocks vs. 14's.
3 inch clearance.webp
RR STUFFED.webp
 
So your saying you have more upward range of motion because the other side is able to articulate lower, and like a lever (center point being the bumpstop) allowing for more movement on the other side?

Well, whats the next step? Lower bump stops, limiting straps, sawzall to the body panels + 4 link it?
 
So your saying you have more upward range of motion because the other side is able to articulate lower, and like a lever (center point being the bumpstop) allowing for more movement on the other side?

Well, whats the next step? Lower bump stops, limiting straps, sawzall to the body panels + 4 link it?

Yes. I always knew it happened, just never realized how much. 3" is considerable.

Next step? Well, it all fits as it is now, so for now, I'll leave it. Maybe see if I can shave an inch off the bumpstops and still clear. Since I've already cut open the body panels (with one of the results being starting the whole interior on fire), the sawzall isn't really an option. The wheel wells are as big as they're going to get without tubbing it. Mostly it just means if I want to go bigger than 37's (I really had my eyes on some 40" LTB's :) ) that I'll have to do something. More bumpstop which means more lift or I'll have no up travel, or limiting straps to keep the axle from drooping so much and puting it at such an angle. Seems counter productive though to limit flex to fit bigger tires. I could move the bumpstop out as far as possible on the axle to limit this effect.

Mostly it's accedemic, as like I said, it works right now, it's just interesting and it's also something that never seems to get discussed when talking about fitting tires. It's always how much lift, how much bump stop, how much triming and there seems to be little or no consideration to what the other side is doing. So just interesting.
parallel compression.webp
slight articulation.webp
extreme articulation.webp
 
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overly simplistic, but this shows a 2.5" gain moving the bumpstops from 24" on center to 32" on center. I don't think there is 4" per side to move the bumpstops out though. Definately overly simplistic, cause I forgot to measure, but it looks like the wider bumpstops might have to be shorter to get full compression on shocks..... depends on shock mounting of course. I guess I really needed a diversion today.....
bumpstops - narrow.webp
bumpstops - wide.webp
 
More of a reason to tube the wheel wells.

and adjust the panhard, and get the right offset on the wheels, ect. ect ect.....

Once you start pushing the limits beyond 35's and 10" travel shocks, life gets interesting....
 
pretty interesting .. how much front and rear movement you got with those long shocks . ? it's marginal or need to be considered in the equation ?
 
Simple geometry is very interesting :flipoff2:
 
You would have to lose the back seat if you were going to tub the rear wheel wells...moving the axle back a bit and limiting up travel would be my first choice if trying to fit 42's.
 
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