deadbeat son
TJ Addict
Thanks for soothing my hurt feelers.
UKTJ
TJ Addict
Very helpful reply. Based on what you demonstrate above, an important factor for any suspension will be the angle of the arms (of whatever length) at ride height. But I also take on board Blaine's first point regarding the materiality of the forward movement.
Yup, sounds like arm angle is simply not a consideration for the vast majority of jeeps.
I hate to keep this thread going, but since we're already discussing it...
The other misunderstanding I have is the claim that long arms ride better than a short arm. I've probably heard this hundreds of times at this point, from lots of folks that don't have a vested interest in it.
I don't understand how that happens, are all of them changing out worn-out shocks and bushings at the same time as the long arm install, and that's what causes the ride quality improvement?
UKTJ
TJ Addict
I've never really looked at long arm kits, but if they cost a lot then maybe it is some sort of pyschological effectbecause they want to convince themselves it is monet well spent?
Legitimate question, and don't flame me for asking it.
How much does this conversation change when you don't rock crawl and are only interested in going fast? I grew up around a lot of Jeepspeed builds and long/trailing arms are common. Is this more of a niche application of stretched/race jeeps?
How much does this conversation change when you don't rock crawl and are only interested in going fast? I grew up around a lot of Jeepspeed builds and long/trailing arms are common. Is this more of a niche application of stretched/race jeeps?
Many things often change at one time with these kits. New springs creating a changed ride height being one of them. That alone can affect how the shocks behave, new or existing.
Trailing arms as in shocks/coilovers attached to the control arm? That is an entirely different discussion from a bolt on long arm kit. Trailing arms start with shock tuning. Shock tuning is where a good portion of long/short arm threads really belong. But very few venture into that realm.
Just a thought, but on a build like you attached, I'm assuming they are running a shock much longer than our measly 10ish inches. At that point arm angles are more of a concern I would assume.
Travel ratios are of interest because this is really a shock tuning concern.
I'm skimming the last dozen pages and skipping a lot of what I assume is Andy's victimized dopey uncle schtick that he won't let me see anymore.
The angle of the arms really doesn't become relevant until the shock travel at droop from ride height is enough that the axle will walk inwards towards the middle of the rig. This is noteworthy during instances of climbing a ledge with an undercut where the tire stops going up and is forced backwards. This can tear the shock in half right before all kinds of other bits get ripped apart. Increasing the arm length can help mitigate the axle walking by improving the angle that the arms are pushing into the ledge face.
I used the term 'long/trailing arm' to specify the build type I was referring to. I would figure these builds use long arms because with the amount of travel they are using, something has to give.
I feel like the folks saying long arms have no real world value are failing to explain that they do have a purpose, though niche.
Again though, I don't build race jeeps.
Please elaborate. What has to give? I already offered one value to a longer arm with regard to axle walk. Has suspension geometry and control arm mounting points been discussed in this thread yet? Any mention of instant centers? If not, then a lot of people here aren't paying attention.
As you explained, travel. And specifically to my point, stability at speed.
I had not read your post at the time of my reply, but it is solid.
I suppose it is possible to have shocks dialed in for race speeds at any arm length, and wheelbase would keep things stable. But wouldn't longer arms reduce the amount of strain on the arms and their joints?
Again I'm not a builder and am more playing the role of curious dude willing to be flamed. Also just a fan of this build altogether.
https://www.motortrend.com/features/0812-4wd-1998-jeep-wrangler-desert-race-car/
The shocks we are referring to would be tuned to the rig and its intended use. The arm length being one of those things the shock tuner isn't asking about.
Arm length has no meaningful impact on the strain on the joints. Those are already reacting against the weight of the vehicle bashing into the things we drive over.
