FOA shock pre-use tune up.

2012SVTSC

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I know, FOAs are frowned upon, but I just wanted to know why, they seem like a good deal.

So here is my little straight out of the box tune up session I did on a pair that I am planing to run on a truck.

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They came black powdercoated, which is nice.
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The seal head and piston, look at the burrs and chatter:

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Deburred, was that so hard?
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Then the Valve stack. Whatttttt? (Piston Deburred in this picture) how can the shims be rusty when they live in oil? They are very bad shims.
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New raptor leaf valve tune stack in:
Mostly king or sdi shims
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Hose upgrade for that rebound assist with the leafs:

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The upper eye is about 1/2" lower than most brand shocks, so you may need to modify any standard mounting, but it also makes the shock shorter.
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The bearings are also quite loose, I went ahead and made some bumpers for mine until I upgrade them.
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Side by side
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Next up: run them and see what happens I plan to add a bleeder to the IFP next time I have them apart.

Okidoke now you know!
 

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Last edited:
I have a set of 2.5x4" FOA bumps sitting under my bench if you want to tear into them and fix em up for $100 lol
 
You basically answered your own question there. They take a little extra work to clean up.
Did you buy those 3.5s new?
Throw some shock boots over the shafts too and avoid the shafts getting dinged and pitted.
 
As they say f-o-a stands for
Fuck
On
Arrival
Sounds like a good time TBH!

I have a set of 2.5x4" FOA bumps sitting under my bench if you want to tear into them and fix em up for $100 lol
Haha No thank you!

You basically answered your own question there. They take a little extra work to clean up.
Did you buy those 3.5s new?
Throw some shock boots over the shafts too and avoid the shafts getting dinged and pitted.
Yes, I wanted to know, now I do. I was just posting my findings for the people here to know, they are brand new... I had planned to take them apart the day I placed the order.
 
Hopefully the piston wear band doesn't pass the hole for your resi fitting, if it does use a spacer on the shaft to keep it away. A large hole like that will rip/damage it. That's why everyone drills several small holes instead of one big one.

The seals that come in FOAs are low quality too. When it's time I believe that shockseals has higher quality kits for them.
 
Hopefully the piston wear band doesn't pass the hole for your resi fitting, if it does use a spacer on the shaft to keep it away. A large hole like that will rip/damage it. That's why everyone drills several small holes instead of one big one.

The seals that come in FOAs are low quality too. When it's time I believe that shockseals has higher quality kits for them.
about .25" of the hole can be covered by the piston wear band at full droop. The rest of the hole is entering the step in the seal head and too low for the piston.

I would never tried something like this on any other shocks but figured I could get away with it on these. I also spent a bit of time trying to deburr the holes that are up inside the shock for the tubes with sand paper and a long dowl, not much effect.

I'll check out shock seals, I ordered a rebuild kit from FOA allready and was going to reverse engineer their seal sizes and order some from a hydraulic shop.
 
Back in the day the machinist / guy behind FOA was originally building parts for Brett King. His idea for the King prerun shocks was cast end caps, which he made about 200 of that was used by King. After that he was trying to cast end caps around uniballs to further cut costs however the quality wasn't there in Brett's eyes and he stopped using FOA as a parts supplier. After that FOA already tooling for most of the shock parts so he started making his own complete shocks. Every one I've ever taken apart needs deburred badly but overall the design has gotten better. Kritter would know but I'd think FOA is similar to King when it comes to measurements. Funny how Kuster, FOA, SAW, and King are all loosely related.
 
I've had some 2.5" x 10" smooth body foas with remote res on the back of my truck for the last 8ish years with no issues or leaks.

I also have some 2.5 x 8 coilovers with remote res that I bought for the front of my truck like 10 years ago and never installed or charged that have sat in the air conditioning in my house the whole time that leaked all the oil out of them within a year or so after purchaing and will need a rebuild to use at all.

Non-bypass shocks are reasonably simple, these are cheap and you get what you pay for. That said, I wouldn't mind picking up another set even knowing I would be rebuilding them as soon as they were delivered. Deburr the parts, hone the cylinder, replace the wear bands and seals and you are in for less than $100. For my current use, they are mostly fine.

When you start getting into bigger bore, longer stroke, higher speed, and bypasses, it is probably not worth trying to go cheap since there is less margin for error. If/when I redo my suspension, I will probably go IBP either king or fox on all 4 corners.

Sean
 
Soooo.... how are they holding up?

Asking for a friend... 😅
Actually no issues so far. They started leaking right away but it was my fault. I torqued down the seal head wrong. After I figured that out I didn't seem to have any issues. I want to spend some time tuning them (don't we all) buttt I've been stuck working and not using the truck too much off road so I can't give more insight now. For cruising and not being super serious they are great for me.
View attachment VID_20240327_191357_1.mp4
 
We did some suspension tuning on a ranger out in Johnson during KOH, Customer informed us he was running FOA's and my instant answer was I'll do my best but I cant make any promises to how they will perform, I was actually surprised how WELL we were able to get the truck to work with just s simple tube turning session, My biggest complaint was the bypass shocks all had top cap remote resi's, other than that and the obvious leaking they are known for, they honestly performed above my expectations.
 
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