Robbie
Robbie UltimaDork
8/26/19 10:06 a.m.

Ok, took apart the front suspension on the challenge AMC to get ready for the challenge. (More details on that coming soon in the build thread). But I'm hoping for maximum eyeballs here for any help or heckling or advice on putting this back together. Here's what I'm working with (shock mounts are above and below):

Also - I had already transferred the collar to the Delco shock:

And:

Constraints (yes I said engineer didn't I?):

1. Budget. This is a challenge car. When we bought the car, technically it had well used but functional bilsteins (s10 4wd front application). We blew them both somehow in the fridgid Detroit winter. So replacing them with similar well used but function bilsteins would be budget neutral. But I can't find any easily, and don't have much time to be searching junkyards and fighting with vehicles that aren't mine. New shocks would by my interpretation of the rules need to be put in budget. We have $50 left. A pair of bilsteins is $150. A pair of brand new AC delcos is $35. 

2. Unfortunately the Delco shock body is like 1 mm larger in diameter than the Bilstein, so the threaded adjuster I have doesn't slide onto the shock. Doh!

3. In the current configuration, there is a collar bolted around the shock, and technically it supports the entire weight of that corner. I don't love the design, and the previous team told us they had issues with those collars sliding up under driving conditions. I'd like to improve if possible.

4. I have other cheap adjusters and threaded tubes that DO fit over the delcos, but with only $15 left in budget that's getting really tight. I'll use them if I have to, but I'd rather find a way to use my existing stuff.

Go!

Btw, if you have some used s10 4wd front bilsteins please please please let me know.

Stampie
Stampie PowerDork
8/26/19 10:11 a.m.

Whatever you do don't let it move. 

boulder_dweeb
boulder_dweeb Reader
8/26/19 10:12 a.m.

My (fuzzy) memory of that frt suspension design says that the top shock mount is engineered to handle shock rebound loads only.

Does that shock bracket area get reinforced to handle the full corner weight?

Rog

Robbie
Robbie UltimaDork
8/26/19 10:14 a.m.
boulder_dweeb said:

My (fuzzy) memory of that frt suspension design says that the top shock mount is engineered to handle shock rebound loads only.

Does that shock bracket area get reinforced to handle the full corner weight?

Rog

Yes, it did:

Dusterbd13-michael
Dusterbd13-michael MegaDork
8/26/19 11:07 a.m.

I never loved that setup. In all honesty looking back I should have looked at motorcycle shocks for the front. It contains the Springs as well as the shocks in a similar package as far as sizing goes.

Robbie
Robbie UltimaDork
8/26/19 11:34 a.m.

In reply to Dusterbd13-michael :

But I love how stiff these front springs are (BTW - one big spring cut into two?). Would be hard to match that with a motorcycle shock/spring. 

I think I might take the simple solution and just use a large diameter tube on the a-arm and flip the spring. That way the spring hat sits on the top tube end, the tube sits on the a-arm, and the free end of the spring sits in the currently unused spring perch. I would lose the adjustability, but that isn't a huge issue if I cut the tube the right length...

Dusterbd13-michael
Dusterbd13-michael MegaDork
8/26/19 12:11 p.m.

Two springs. 800lb/in if i remember correctly. 

I dont see why your idea wont work, but i remember there was a good reason we did it the way we did. I just dont remember what it was. 

Knurled.
Knurled. MegaDork
8/26/19 12:46 p.m.

The Bilsteins probably blew because they require gas pressure for the seals to seal.  Pressure drops in winter, seals stop sealing.

 

I wonder how cheaply you could get them refilled and recharged.  Lots of people weld service ports on them so they can recharge them by themselves.

Robbie
Robbie UltimaDork
8/26/19 12:57 p.m.
Knurled. said:

The Bilsteins probably blew because they require gas pressure for the seals to seal.  Pressure drops in winter, seals stop sealing.

 

I wonder how cheaply you could get them refilled and recharged.  Lots of people weld service ports on them so they can recharge them by themselves.

Well, that might work for one of them. The other - snapped a shaft because Detroit potholes on a blown shock. Or maybe just because Detroit potholes. 

noddaz
noddaz SuperDork
8/26/19 12:57 p.m.

I have wondered if you could take off the upper arm and substitute a McPherson strut assembly.

Knurled.
Knurled. MegaDork
8/26/19 1:01 p.m.

In reply to noddaz :

Me too.  Might be a little late now for that though.

 

I forget the geometry layout of those AMCs, but by my thinking, a front strut from a fullsize GM front-driver might have the right bolt pattern.  Bumpsteer would be "fun" to sort out.

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