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Has this been done before????


Well-Known Member
It's been done before and still used by some non off road applications. Kinda overrated. Hard to tune plus Lots of seal friction.

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Samco Fab

Well-Known Member
Possibly a lot of buckling load with an eyelet to eyelet length that long, and a 1" shaft at the most venerable mid section. Dynamically shocks see a lot of bending load pounding jumps and whoops, especially if they are laid down at an angle. I bet $1 that the shaft bends. Kudos to creative thinking though, I am not hating.

Upper shock mount would be around roof level I would guess as well.


Well-Known Member
Besides being so long, it makes the bypass shock pointless. If you add stiffness with the bypass adjusters, the CO side will just move more and there will be no change in stiffness. If you add a ton of valving to the CO to make it stiffer, it will quickly overheat.


Well-Known Member
Thought King made a shock like that years ago. I want to say it was called a Coil Pass shock? I think they were being used in Short Course racing, back in the CORR days. I pretty sure a UTV or two had used them too.

Edit: Rocket450 beat me to it! Good news is my memory was right.
Thanks for posting travis. I lost my old acct into.

The coilpass was half a bypass. That's something that'll hang rebound. Drag compression then change when it hits the tube section. This is a full 3" 5 tube pure race 16" shock. Yes it's long. It doesn't have to be but it fits the application with simple mounting. The threaded body is just that. No function internal. It passed some engineering concerns. We'll see how it works. It's an experiment for a single shock class and nothing more. If it works great. If it fails... at least I tried something.


Well-Known Member
I swear i have seen something like this before. If not this could be something big in the shock world. What are your thoughts. Sharing for a buddy who built it.
Why are the coils so long? As was mentioned the shock/shock shafts will buckle due to forces. If your buddy likes the setup/idea I am sure he can refine the concept. Seems to me if anything it would definitely work better on a lighter vs heavier vehicle.

John Bitting

There were pics posted many years ago of this, I want to say maybe Ryerson? Gold shock with a couple of small bypass tubes on the top of the shock body, coilover down below. I will search.
It's not that long..... let's assume I'm not an idiot. Maybe I am but I have a 16" 2.5 fox co running 150 degrees on a trailing arm making 22" travel in a similar application. This one is axle mount. Should be testing this weekend so we'll see what happens. The bypass is unmodified so if it doesn't work... it can live it's life as a bypass again


Fly'n Ryan

Well-Known Member
Aymar Engineering designed these bad boys back in 2005. Revolution Racing Shocks. Internal bypass external coil over. They were designed to save weight. I see them every now and again on smaller cars, but I am surprised they never went big!!!



Crayola Killer
Mickey Thompson built Challenger V in 1980 to replace Challenger IV (my car). He was a shock expert and worked with other shock guys to develop his own shocks. The more I learn about Mickey Thompson and the stuff he was trying back in the day the more I understand what a true genius he was. MT's only problem was he never fully had the time to perfect his designs because he would always think of something else that would take him away from perfecting whatever it was he was working on. Just look at the pictures below, how close was he to having a 2.5 KING coilover/by-pass back in 1980? Could you imagine what would have happened if he perfected it back then and the jump in technology from 1980 to the early 90's when these shocks became readily available? Boggles the mind...


MT shock.jpg

MT shock2.jpg


Well-Known Member
I guess I'm not understanding the purpose of the lower threaded body/coil carrier if there is no valving in it? Why not just make the lower mount with a spring retainer for the bypass?

Whether it works or not, I can appreciate the effort to think outside of the box.
You have to have so much spring to not coil bind. The coil body is to allow ease of preload adjustment. On a dual rate. Technically you should have an 18 and a 16" spring (not pictured but they'll fit) the lower body is nothing more than an extended eyelet.


Well-Known Member
Also if you look at your setup vs the King "coil pass" you can clearly see that the top collar on the spring goes up the shock body a decent amount. Your setup the collar can't go up due to the bypass tubes.

I definitely can appreciate this king outside the box. I just don't see it working though, I am no shock expert and have been wrong in the past and will be wrong again in the future.
That's the point of my redesign. You get the entire function of the bypass. Why would the collar need to go up the bypass? Lol just let it play out before you speculate it to death. It's nothing more than a bypass shock with a full dual rate spring setup. Once again it just to make the 4800 class shock less limited. I'm not a big fan of the ibp. Hence where this came from.