I can imagine the hootin' n hollerin' as each Jeep rolls over the scale!
*Cough* Fat *Cough* Light bars weighing him down. *Cough*
I can imagine the hootin' n hollerin' as each Jeep rolls over the scale!
Your 37s/18" hub vs my 33s (285 75r16s)/15" hub. Do you see it? I'm starting a thread...I can't remember if I already said it, but my 37s are giving a 18" hub height.
Would rather use tire roll out to measure circumference and use that to calculate tire radius.I can't remember if I already said it, but my 37s are giving a 18" hub height.
Your 37s/18" hub vs my 33s (285 75r16s)/15" hub. Do you see it? I'm starting a thread...
But I think we're doing pretty good here for quick and dirty data.
Let's find out more....My radius is 2" bigger. We have a 3" difference.
A few disclaimers: I suspect my tire pressure is a little high at 25psi. I am also missing a few hundred pounds of fuel, cage, fenders, carpet, top, etc.
Due to the lower mounts being below centerline of the axle tube and thus the center of the tire, you can NOT adjust either the upper or lower arms without changing both wheelbase and pinion angle. That and if you raise the pinion, you won't be sacrificing wheelbase since the axle would move back at the same time the pinion comes up. Raising the pinion adds wheelbase.You should be able to raise the pinion angle without sacrificing wheelbase...the Upper arms control that. Lower arms primarily set the axles fore/aft position, the uppers control rotation, and a trackbar controls the side to side motion. Now...In @jjvw's case, he's running triangulated links, so he doesn't HAVE a trackbar, but his pinion angle is still set with the upper control arms.
Due to the lower mounts being below centerline of the axle tube and thus the center of the tire, you can NOT adjust either the upper or lower arms without changing both wheelbase and pinion angle. That and if you raise the pinion, you won't be sacrificing wheelbase since the axle would move back at the same time the pinion comes up. Raising the pinion adds wheelbase.
Nope. I missed yours. I'll post a current summary after a few more add theirs.Interesting, even Im not in list. But mabey I did some wrong
Don't worry about it. I've been fighting that bit of misinformation for years. I've even seen well known smart companies say the same thing.Thanks. @jjvw mentioned that too, and as I started to think about it, I realized why what I said was incorrect. I should probably go back and delete the comment.
Nice data and charts!If you know your hub height and/or actual spring measurements, also let me know.
Something that is hopefully starting to become visible is that these measurements are meaningful and do add up in ways that make sense. The actual tire dimensions (hub height) added to the actual coil/spacer heights will closely correlate to the frame height. This ought to be fairly consistent from TJ to TJ.
If there is one thing for anyone to take away from this, it is that the advertised sidewall and lift measurements are not true to life. We can see these errors in the charts.
If we could get the data actuate enough, an interesting thing we may get to see are the unaccounted height changes found in the spring seats that are in non-stock positions.
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I also think we could work on another set of dimensions at least for the rear springs which are notoriously difficult to measure in the stock configuration. I'll try to check today and see if I can find out if a top of axle tube to top of frame arch will work to extrapolate backwards to actual spring height.
We measure this stuff all the time doing outboard work and we don't even try to measure the stock rear perches. Even with two guys who have worked together a long time on opposite sides of the rig making sure everything is in the same location we can't get it accurate enough to trust. My middle may not be exactly his middle of the upper perch and since it is sloped, any minute shift front to back will give a different dimension side to side. I'll ponder it some and see if I can come up with an accurate way to measure.The rear is especially difficult to measure consistently. In my head, it makes sense to measure at the middle between the seats. It can be hard to get a tape measure in there. But that should average out much of the bow caused by the non-parallel seats. Really, consistentcy in measuring is the most important thing.
Some of the hub heights look a bit odd. If anyone would like a dead nuts accurate hub height without using a tape measure, post up a given verified accurate speed and RPM with year and transmission and we can run that through the gear calculator to get a very accurate hub height.