Modifying front trailing arms

[fredc125]

I'm running 2.5" over front trailing arms on my sandrail but find I still need more travel. 4" over trailing arms new are quite expensive so I thought why don't I just extend the ones I have. Then I thought well heck I could make them 5" over and be even better but Something tells me it couldn't be that easy and there's to much I don't know about this topic to be able to make an educated decision on what to do. Any wisdom here would be greatly appreciated. THX.

[CentralWAbaja]

Where there is a will there is a way. But I will say the aftermarket world stops at +4 for a reason. Actually a few reasons. Mostly too much leverage and the bump steer gets a bit out of control after that 14-15inches of travel that a +4 can produce. Bumpsteer simplified is as the wheel travels to the extremes of the travel the tie rod just naturally runs out of length causing the tires/wheels to point out (Usually)

I would probably opt to make my own arms vs modifying something but I have seen where guys have done it. There was a guy in Texas a few years back racing with some heavily modified stock stuff. He passed away a couple years ago. People told him his stuff would never hold up so he was hell bent on proving everybody wrong. From a distance he seemed a bit off his rocker , but mu friends in the Texas racing scene said he was a likable dude.

[fredc125]

I appreciate your response. The trailing arms have a section towards the end of the tube where it's just straight clean tubing. I was thinking it would be real easy to cut it in the middle of that section then add a thick walled piece of steel tube sleeve to extend the overall length. Should be strong. I'm looking for reasons I shouldn't do it. Sure cheaper than new ones.

[Ol'fogasaurus]

I've thought about this quite a bit since you posted it and, for several reasons, I don't thing "I" would do it especially using the sleeving method. I'm not sure if the trailing arms are cast, forged, or what but sleeving probably would get to be pretty complicated and would require additional machining of the arms to fit tightly inside of the tube along with special welding to make the arms join into a tube so to handle the loads. Also, the tube would have to be DOM because of the different angles that any loads would/could come in at.

If I were to do it (I don't weld good enough to even consider it, except for your question, as it is well above my skill level and the welding setup I have. Since I am not sure of the material of the arms themselves, the tempering... if done, and method of forming it so it might be easier to do it you used two arms per unit then cut and fit them into the longer length you want... if possible; again, there is the welding problem. Again, the welding and grain direction is important here mainly because of the amount of loading the arms could receive.

Have I touched everything... no, I don't think so.

This is an opinion and I am posting it for what it is worth.

Lee

[fredc125]

Thanks Lee. Here's a link to the arms I have https://www.pacificcustoms.com/ac413080-225c.html Maybe It would be wise to add a tube inside as well as outside for more strength. There is a pro metal fab shop not to far from here, I may drop in there and get their opinion as well. Thanks.

[Ol'fogasaurus]

Thanks Lee. Here's a link to the arms I have https://www.pacificcustoms.com/ac413080-225c.html Maybe It would be wise to add a tube inside as well as outside for more strength. There is a pro metal fab shop not to far from here, I may drop in there and get their opinion as well. Thanks.

"Whoof!" I saw the prices and I almost loaded my drawers!

It looks like someone who knew what they are doing designed the two different style of 12" travel arms. To get another opinion is not a bad idea but I would suspect (hope) that the designer for PC has had to take some of the other related factors into consideration for these designs. It wouldn't hurt to ask them before you spent that wad of "moolah".

(For what it is worth) I forgot to mention that if you cut the arms then added the tubes you would have had a minimum or 2 weds plus the backup plug welds. As I have said before: I am not an engineer but did work in engineering so I have some ideas of things but not to the depth that an engineer or specialist would (I hope) have.

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An other way is to do the tube arm things of which there are several designs out there. This is an A-arm style, on a rail, that uses uni-ball spherical rod ends which gives a lot of travel from what I have been told (I can't ride in or drive a rail [in just a few feet] w/o getting motion sick or I would have one and not fight the glass buggy I am building now).

Some of the users of this have the pivots towards the center of the rail and there is another style of arm that uses the MII style of rear part of the arm that pivots close to where the firewall would have been. (I'll try to edit a couple of other pix I have of this or similar styles so I can post them later).

Lee

[Ol'fogasaurus]

I modified some more pix I took many years ago (the rail is still being used I think). The main reason I took them was this was the first time I had seen electric power steering on a rail.

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The last one shows the power steering box in place.

Lee

[fredc125]

I fabricated a front a-arm setup for my last rail and it worked very well. However it did take some effort and money and time. My current rail has a good warrior beam setup which I have seen (on another car) work very well. Mine doesn't. Since the beam setup is so tough and already paid for I would like to get it working good if I could do so on the cheap. I figure I could lengthen those arms for under $50 and I'm pretty confident that it could be super strong. It will be sometime before I get to it but I will post an update when it's all figured out. Thanks.

[Ol'fogasaurus]

I looked the the Warrior beam up and there are both K&L and BJ but am I right assuming that it is K&L?

Did it come with shock towers or not?

What kind of problems are you having with it? (several reasons for this question)

It will be interesting to see what you do and how you do it so please keep me/us up-to-date on what you are doing.

Lee

[woodsbuggy1]

Please post some pics of your front end. Is your beam 6" wider than stock? Are you running coil over front shocks? If you want to run 1X4 front arms you need both of these. I have built and installed my 1X4 arms on quite a few buggies and they work very well when properly set up.
Kenric

[CentralWAbaja]

"Whoof!" I saw the prices and I almost loaded my drawers!


Lee

You thought that was sticker shock? Here is the full State of the art Race set up.

https://jakesfabworks.square.site/produ ... /7?cs=true

[CentralWAbaja]

I fabricated a front a-arm setup for my last rail and it worked very well. However it did take some effort and money and time. My current rail has a good warrior beam setup which I have seen (on another car) work very well. Mine doesn't. Since the beam setup is so tough and already paid for I would like to get it working good if I could do so on the cheap. I figure I could lengthen those arms for under $50 and I'm pretty confident that it could be super strong. It will be sometime before I get to it but I will post an update when it's all figured out. Thanks.

My bet is that if the beam is not working well it has nothing to do with the arm length, and everything to do with the entire package setup, including rack placement, upper shock mount placement, spring rates, and valving. And maybe a few other items. I have seen way too many 5-1600 race cars with beams that work really well and those are limited to +1" arms.

My opinion is you could end up with the arms braking at the HAZ right next to where you weld in the sleeves. Baja-5 broke a couple tweeds arms right in the middle of the arm a few years ago on his baja bug. His solution? A-Arm Thing LOL

[Ol'fogasaurus]

Pix would be a very good thing to post as we are just guessing.

By-the-way, this sounds like a silly question but are you still using the torsion leaves in the front?

Lee