Long Arm Build for a TJ - Page 14

gtospeeding · 09-07-2009, 09:55 PM

Does anyone have a pair of front upper control arms laying around after their long arm install?
Im doing an experiment and need a pair with good bushings

06rubcion · 09-07-2009, 10:25 PM

jmop i would have done jj on both ends and not used bushings, they limit flex

**Tommy R** · 09-08-2009, 08:22 AM

Quote:

Originally Posted by 06rubcion

jmop i would have done jj on both ends and not used bushings, they limit flex

They also cost more and my shocks already get maxed out with the flex I've got. And in the front, you can't use JJs on both ends for reasons that have already been discussed here.

Jeepinty · 09-08-2009, 05:12 PM

Tommy, I got to see your jeep up close this weekend at Trees (I was the guy camped next to ya'll who borrowed the lighter). Anyways, I was impressed by the quality of the build using minimal tools and a basic knowledge of suspension geometry.

As far as the radius arms are concerned, a friend of mine ran a basically stock RE long arm kit on his TJ buggy for years and had a rediculous amount of flex running a D60 and 37 Krawlers HARD. I never saw him twist anything or shear a bolt. I would strengthen the stock passenger UCA mount if you keep running it though.

Awesome build, keep up the good work.

**Tommy R** · 09-08-2009, 05:28 PM

Thanks a lot! You should've introduced yourself. Always nice to put faces to (screen)names.

What I'm thinking about doing now is build a true upper third link on the driver's side. Instead of the OEM bushing, I'll look to replace it with a Currie insert like in this kit:

Jeepinty · 09-08-2009, 05:33 PM

Honestly I thought about it but figured you get that a lot. I have a hard enough time remembering names myself, lol. Anyways, I like the idea of a true 3 link front, should get rid of any binding that may be present. Interested to see the turn out.

**Tommy R** · 09-08-2009, 05:51 PM

I appreciate the consideration, but I'm always up for meeting folks. Next time come on by and have a beer with us.

Jeepinty · 09-08-2009, 07:10 PM

I'll keep that in mind. One question about your radius arms though. I think you used the 2.5 inch JJ for the short radius arms but I'd have to look back. I think RE uses the smaller joint for the link end of the short radius arm. That is my reasoning behind building me some rear uppers (to adjust pinion angle until I can do the long arm build) and using the stock 2" size that can be reused as the radius arms later on.

ET48 · 09-10-2009, 05:20 PM

Is there any reason why you couldn't take the lower control arms all the way towards the center of the skid to make them even longer?

(Shown below) Utilize one mount per side for both front and rear lower control arms. Just an idea.....

tweba99 · 09-10-2009, 07:12 PM

Quote:

Originally Posted by ET48

Is there any reason why you couldn't take the lower control arms all the way towards the center of the skid to make them even longer?

(Shown below) Utilize one mount per side for both front and rear lower control arms. Just an idea.....

I will help on answering this one......

When building long arms, it is all about the geometry/wheelbase and that is what determines the length of your arms. You have to also take into account that the longer the control arms, the more the chance that they will get bent while playing in the rocks.

ET48 · 09-10-2009, 08:23 PM

Quote:

Originally Posted by tweba99

I will help on answering this one......

When building long arms, it is all about the geometry/wheelbase and that is what determines the length of your arms. You have to also take into account that the longer the control arms, the more the chance that they will get bent while playing in the rocks.

I can see the geometry having an effect on the length of the arms, but my wheel base determines the length of the arms......that makes no sense.

Why then would you be able to run short arms and long arms?

churchofjt · 09-10-2009, 10:39 PM

I'm no expert certainly, but I think I could see the wheelbase determining things like instant center and what-not. I think that if you messed with one dimension like the link length, it might throw off the squat. Am I way off track?

tweba99 · 09-11-2009, 06:15 AM

Quote:

Originally Posted by ET48

I can see the geometry having an effect on the length of the arms, but my wheel base determines the length of the arms......that makes no sense.

Why then would you be able to run short arms and long arms?

Height, wheelbase and tire size have to do with the length of the arms which all determine where your instant center is. Go over to pirate4x4.com and you can learn ALOT about building suspensions, how they work and it will probably answer any and all questions that you have.

Quote:

Originally Posted by churchofjt

I'm no expert certainly, but I think I could see the wheelbase determining things like instant center and what-not. I think that if you messed with one dimension like the link length, it might throw off the squat. Am I way off track?

You are correct.

ET48 · 09-11-2009, 11:13 AM

Quote:

Originally Posted by tweba99

Height, wheelbase and tire size have to do with the length of the arms which all determine where your instant center is. Go over to pirate4x4.com and you can learn ALOT about building suspensions, how they work and it will probably answer any and all questions that you have.

Sounds like a good plan.....

**sebastian22** · 10-23-2009, 12:34 PM

Great thread! Does anyone know where I can find bushing sleeves?

Edit: Found it! Post 97 and 98 if anyone else has the same question. Rubicon Express part # RM12600. My bad for not reading everything.