Not your mama's long arm debate

[D M]

All right keyboard warriors, get ready to crack your knuckles and start typing All jokes aside, i'm creating this thread because I want your unbiased opinions of the Long arm vs Short arm argument. I am going to remain neutral since I have only run short arms, but I want people's actual opinions on the geometry and how they work, no not because someone got stuck on a rock. I know this forum is very group opinionated (nothing wrong with that ) but I want to hear from both sides of the argument from people who have used them and actually wheel.

 

[D M]

I can understand how people don't like the fact that it takes away a majority of your break over angle, but take a look at nth degree long arms where it basically hides the "long" length with the frame until it peeks out basically back at the "short" length

 

[02GreenTJ]

Not trying to defend long arms, but we have to wonder, maybe if Jerry wasn't wearing his eyepatch he would've seen that rock.

 

[vinsanity]

The short vs long arm discussion changes depending on what you are building. If you are looking for 35s with a 4-4.5" lift and stock axle locations, most people will argue that quality short arms will out perform poorly geometry long arms, and most bolt on long arm lifts fall into that category. That said, I have no personal long arm experience in this setup.

If you're talking about a stretched with 37"+ tires the discussion changes entirely. There is a much stronger case for long arms here.

 

[D M]

The short vs long arm discussion changes depending on what you are building. If you are looking for 35s with a 4-4.5...

I agree with you on that. I can see why people get pissy when they have huge long arms on a jeep thats only on 35s, its alot of ground clearance but not really enough to the point of 35 inch tires and long arms. That's why I agree with you about the long arm and 37s. 37s are basically the minimum (from what ive just seen) where you can "comfortably" run Long arms due to the height

 

[jjvw]

The debate is absolutely pointless and entirely useless until the fundamental purpose of changing the control arm mounting locations is explained. Most get this wrong from the very beginning, including almost all of the kits.

If you think longer arms are automatically better arms simply because they are longer, you don't belong in the discussion.

 

[someguysjeep]

link length is a byproduct of the distance between mounting points.
where those mount points are located in relationship to each other controls the geometry of the suspension.
the longer the arm, the more you effect the links vertical angles and horizontal trajectory's.

so it's more of whats the best compromise for MY/YOUR lift height and wheel base, not whats better for a Jeep TJ.

it also boils down to YOUR primary purpose.
you can cheat your DD to deliver the ride you desire. if you cheat the trail rig your building, your only cheating it's ability to perform.

does anyone have a stock TJ suspension set into a calculator, accurately?

 

[mrblaine]

All right keyboard warriors, get ready to crack your knuckles and start typing All jokes aside, i'm creating this thread because I want your unbiased opinions of the Long arm vs Short arm argument. I am going to remain neutral since I have only run short arms, but I want people's actual opinions on the geometry and how they work, no not because someone got stuck on a rock. I know this forum is very group opinionated (nothing wrong with that ) but I want to hear from both sides of the argument from people who have used them and actually wheel.

In the simplest form, long arms are not terrible enough to go back to short arms and short arms are not terrible enough to go to a long arm set up all other things being equal with typical lift heights, wheelbase, and tire sizes.

 

[Southtowns27]

Interesting thread. I'm on short arms and have no complaints. I do hear a lot of guys say that none of the bolt on long arm kits have good geometry. Can someone explain this in technical terms? I want to know exactly why or what makes the geometry poor

 

[mrblaine]

Interesting thread. I'm on short arms and have no complaints. I do hear a lot of guys say that none of the bolt on long arm kits have good geometry. Can someone explain this in technical terms? I want to know exactly why or what makes the geometry poor

Packaging. You can't extend arms to the skid plate and get enough vertical separation at the frame end of the rear upper arms because they will crash into the bottom of the tub on uptravel. To stop them from crashing, they lower the mounts so they can be bolted in. Packaging in favor of geometry. Rough Country is the absolute best at it since they put both upper and lower arms in the mount on one single long bolt.

 

[Southtowns27]

So it's got a negative effect on antisquat and antidive?

 

[Chris]

Wait, isn’t there a 10 plus page thread about this

 

[Goatman]

I have read only one opinion on this topic from the magazines I've read for years. LONG ARM ! Seriously. It is what every mag pushes. I think if, starting from a bone stock TJ, you design for long arms (note the word 'design' and not 'click the button') from the very beginning then you have a very good chance of building an excellent rig. But how many actually do that?

On this (and others, tho not all) forum it is decidedly for SHORT ARM or you are just plain stupid. If (my opinion) desert whoops are your thing then I lean towards long arms. If rock crawling, then short arm. The long arms can provide a much softer axle movement with proper spring/shock placement. But it does obviously cause some low hanging fruit to catch in big rocks.

I would think a short arm using frame side drop brackets would be a good solution to either side's argument. Allowing much better control arm angles when using longer springs and still keeping the belly free from the rocks. I'm sure there is a good argument against this idea, other than leverage on the bracket because well designed drop brackets would be designed with that in mind.

As far as the long arms not having room on the frame for correct geometry between the upper and lower, most I have seen just have the lower attached to the frame with the upper arm connected to the lower. A radius arm suspension has been used by just about every auto company. R. Rover and Ford has for decades on their 4×4s. And it works well for them.

So the long vs. short has a lot more "shades" than just black and white.

 

[Chris]

LONG ARM ! Seriously. It is what every mag pushes.

I can't tell if you're being sarcastic or serious.

In the case that you are being serious though, you don't think that has anything to do with the these magazines being paid by their advertisers (i.e. Rough Country, Rubicon Express, etc.), do you?

So the long vs. short has a lot more "shades" than just black and white.

I couldn't disagree more. If you're read these discussions and done the research, you'll pretty quickly realize that it comes down to an issue of packaging, and there is simply put no "bolt-on" long arm lift that doesn't compromise one thing for another.

If you want to make long arms actually work (which at that point you can call them whatever you want, long arms, mid-arms, medium arms, etc.), it's going to involve cutting and welding, not a "kit".

 

[mrblaine]

So the long vs. short has a lot more "shades" than just black and white.

Not really.

 

[someguysjeep]

no space on a TJ for LA's to carry enough vertical separation at the frame side.

after about 2" of lift the SA sys does a real shit job of controlling the axles from scissoring in and out during suspension travel. the higher the lift the worse it is.

so where's that leave us....................wheres the spot you could maintain proper link separation and minimize the amount of axle scissoring.

I.......< it's not this end, SA.................................>>i<<........................................it's not this end, LA >.......I

bottom line is, how can we fix the worst part of the LA sys to compliment fixing the worst part about a SA sys.



b4 you bust out the sawzall..........does it even matter in your situation?

 

[mrblaine]

I can't tell if you're being sarcastic or serious.

In the case that you are being serious though, you don't think that has anything to do with the these magazines being paid by their advertisers (i.e. Rough Country, Rubicon Express, etc.), do you?



I couldn't disagree more. If you're read these discussions and done the research, you'll pretty quickly realize that it comes down to an issue of packaging, and there is simply put no "bolt-on" long arm lift that doesn't compromise one thing for another.

If you want to make long arms actually work (which at that point you can call them whatever you want, long arms, mid-arms, medium arms, etc.), it's going to involve cutting and welding, not a "kit".

All of this is based around the erroneous conclusion that arm length and angle affects ride quality and within typical lift heights that is not true.

 

[Brian83]

I have nothing to say other than the travel of my fox shocks in the factory location limit the axle droop with my short arms so how could I possibly gain any flex by changing the control arm length?

 

[freedom_in_4low]

I have nothing to say other than the travel of my fox shocks in the factory location limit the axle droop with my short arms so how could I possibly gain any flex by changing the control arm length?

that's where I'm at. My shortarms are not the travel-limiter in my suspension so until I start hacking the shock mounts and the frame to get more shock travel then I see zero benefit to longer arms.

 

[someguysjeep]

I have nothing to say other than the travel of my fox shocks in the factory location limit the axle droop with my short arms so how could I possibly gain any flex by changing the control arm length?

you can't. your the shocks are your limit.