Trialing Arm Alignment Check/Service Options

[friethmiller]

I would like to check the alignment of my trailer arms before I recondition them for the LE. I know there's a Lamont guy in CA that had a jig for 914 trailing arms, which he used to reinforcement the arms. My main concern is the driver side that got hit in an accident long ago. Does anyone know of anyone that can do this check? Tangerine Racing no longer does it and Elephant and PMB provide a reinforcement service. Is there any way I can DIY?

[technicalninja]

(IMG:style_emoticons/default/popcorn[1].gif)

I'm interested in what other members come up with...

Having a "Jig" would be most helpful.

I think you're going to have to make one yourself!

Metal fabrication skills will be a requirement, patience too!


I know this guy down in Austin...

I DO have 100% absolutely straight arms completely bead blasted right now that might be a reasonable buck for the jig.
You could borrow them...

[friethmiller]

I DO have 100% absolutely straight arms completely bead blasted right now that might be a reasonable buck for the jig.
You could borrow them...

Maybe when your friend Eric calls me about my engine parts I can [finally] come up with those spare 96mm jugs.

[mepstein]

I bet you could do a check on a flat surface with some pretty average measuring tools.

[mlindner]

Why don't you check your alignment first....if good or within adjustment then just add the reinforcement clam shells. Best, Mark

[friethmiller]

Why don't you check your alignment first....if good or within adjustment then just add the reinforcement clam shells. Best, Mark

That would normally make sense @mlindner but my car looks like this right now. I guess I could completely assemble everything and check alignment. (IMG:style_emoticons/default/idea.gif) I think I want to tackle this problem before I get the car back on its wheels. All the suspension components are going to get powder coated soon.

[Montreal914]

Too bad CFR doesn’t do these anymore.
I liked his way of reinforcing the arm with the added middle partition. Nice way to stiffen that long box.

Other than catastrophic bend, do the trailing arms often bend without showing any signs (cracks, bulges, etc)?

[mepstein]

Too bad CFR doesn’t do these anymore.
I liked his way of reinforcing the arm with the added middle partition. Nice way to stiffen that long box.

Other than catastrophic bend, do the trailing arms often bend without showing any signs (cracks, bulges, etc)?

Possibly, since they are steel, they can bend without necessarily showing damage. I would set them down on a flat surface, opposite each other and just see if they are mirror image to each other. A visual inspection with a critical eye can get you 95% there.

[Dave_Darling]

There is a measurement in the Haynes manual (photo and measurement taken from the factory manuals). I don't remember what it is off the top of my head, but thumb through the manual. It's a photo of the trailing arm from the side, with a couple of parallel lines drawn and a measurement, I believe.,

--DD

[mlindner]

This sounds like a job for Ben McFarland. He knows 914s up and down and is a excellent welder and fabricator. Mark

[bdstone914]

friethmiller
' date='Apr 8 2025, 10:01 AM' post='3200238']
I would like to check the alignment of my trailer arms before I recondition them for the LE. I know there's a Lamont guy in CA that had a jig for 914 trailing arms, which he used to reinforcement the arms. My main concern is the driver side that got hit in an accident long ago. Does anyone know of anyone that can do this check? Tangerine Racing no longer does it and Elephant and PMB provide a reinforcement service. Is there any way I can DIY?
[/quote]


Edit. I see it is the drivers side for a 74.

I would get a replacement from a car that has not been hit. I probably have a bare arm cheap. Which side and year?
I did sell one to a shop that could not get the alignment specs on one corner. You could not tell the arm was bad.

[friethmiller]

There is a measurement in the Haynes manual (photo and measurement taken from the factory manuals). I don't remember what it is off the top of my head, but thumb through the manual. It's a photo of the trailing arm from the side, with a couple of parallel lines drawn and a measurement, I believe.,

--DD

Thanks Dave. I'll check the Haynes manual. That I do have.

[friethmiller]

I would get a replacement from a car that has not been hit. I probably have a bare arm cheap. Which side and year?

Bruce, you reminded me. I think I should have an extra set of trailing arms from another '74 that I parted out. (IMG:style_emoticons/default/idea.gif) I'll go look out in my shed.

[seanpaulmc]

There is a measurement in the Haynes manual (photo and measurement taken from the factory manuals). I don't remember what it is off the top of my head, but thumb through the manual. It's a photo of the trailing arm from the side, with a couple of parallel lines drawn and a measurement, I believe.,

--DD

[technicalninja]

That is the INCORRECT way to align the outer trailing arm BUSHING mount!!!!!

EVERY single non-rotating (rubber) bushing should be locked down at or slightly BELOW normal ride height.

Not just 914s

Everything!

That page also says "Bushings are part of arms and cannot be replaced".


Now, use a bushing or bearing that rotates...

Lock position doesn't matter at all!

[friethmiller]

...

I'm sure the DAPO, drove it "moderately" to the Porsche Dealership to verify suspension alignment. (IMG:style_emoticons/default/lol-2.gif)

[Maltese Falcon]

You can always MiG weld a basic steel structure (jig) for checking the Left and Right arms. Of course you will need 2) Good arms to form a 'Correct jig for this purpose. I use ours for reinforcement plate welding>> keeps the arms from deforming.
(IMG:style_emoticons/default/welder.gif)

[friethmiller]

You can always MiG weld a basic steel structure (jig) for checking the Left and Right arms. Of course you will need 2) Good arms to form a 'Correct jig for this purpose. I use ours for reinforcement plate welding>> keeps the arms from deforming.
(IMG:style_emoticons/default/welder.gif)

Excellent! I would build I jig if I were doing something like this. No doubt. I just want to check the alignment for two for my LE. If you or somebody else could do this for me, I'd certainly pay for services rendered.

Let me know. Thanks (IMG:style_emoticons/default/smile.gif)

[technicalninja]

You should bribe or blackmail the Falcon into giving you "blueprints" or measurements...

The KICKER here is "I use ours for reinforcement plate welding>> keeps the arms from deforming."

You need this, I need this.

I've got good straight arms as templates. They are currently off of the car!

You can weld quite nicely...

Might be handy to have adjustable camber angle worked into the jig so you modify base camber adjustment ala Tangerine Racing.

Edit:

Montreal's note about "CFR" not doing control arms any more worried me.

I was planning on having Tangerine Racing do any arm mods I needed.

The box style of re-enforcement that he did looked like "best engineered, strongest, and possibly lightest" in my book. His angular arm to bushing tube gussets looked kick ass as well.

His website no longer lists this service.

Sad Ninja...

[Dave_Darling]

Shoot! That was the photo I was remembering, but I mis-remembered that there were measurements associated with it.

--DD