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Just got these in from Greg today. I've been spending some late nights trying to get this stupid thing ready for GONE. I leave saturday morning.
Here goes...



There is NO room on that passenger side to mount the resevoir to the shock body. What I ended up doing is mounting it to a square frame crossmember. Even then, the hose to the resevoir is a little to long. I had to twist it to curl the hose and shorten the length a little bit, unfortunately this brings the hose a little to close for comfort to the exhaust line. I'm going to try to find some hose heat wrap to cover that up. The zip-ties are only for tonight, as I need to get some bigger hose clamps to be able to mount it to that crossmember.

The drivers side wasn't so bad. These are pretty sweet shocks. Greg got the shock length perfect for me.
 

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Ahh, finally got the right set-up in there. Sorry it took so long. Looks great though. I told you they are a tight fit w/ the res hoses.
 

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Looks good. What are you doing for setup again? It has changed so much I am lost!

Enjoy Gone!
 

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kokopop said:
Looks good. What are you doing for setup again? It has changed so much I am lost!

Enjoy Gone!
He has 0-3" radflo's with TC ucas in front. In rear... It looks like he has AC shackles (not positive) and he has alcan leaf packs.
 

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Shocks work because a valve moves slowly and evenly down through a substance like nitrogen to "dampen" what would otherwise be the continuing up-and-down motion of the springs. The substance gets hot, and begins to froth and work less well, especially when you're doing things like hammering through whoops and washboards in the desert for hours at a time (my favorite thing to do besides one other thing I can think of). The reservoirs supply more of the substance than can fit in the shock tube, and thus greatly increase the shock's dampening capacity. Without a reservoir, in hard driving, shocks fade and fail.
 

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The reservoir's main pupose is to offer a place for the displaced oil to go as the shaft of the piston goes into the shock body. Imagine a bucket full of water, to the brim, then you make a fist and put it in the bucket. The water will overflow. That is the res. primary job. Now, inside the res is a floating (or dividing piston) and on one side is the shock oil the other is the nitrogen. The nitorgen acts as a spring (you could easily replace the nitrogen with a coil spring to do the same job) to hold the column of oil in place. Here's the fun part. Fluid can't be compressed, but the molecules can be stretched. The nitirgen puts pressure on the colum of oil that is inside the shock body. As the piston gets pushed in this column it will try to seperate the oil molecules (called cavatation) by pushing the column of oil into the reservoir but the pressure exurted from the nitrogen holds this column of oil in place but still allows a slight bit of movment to allow for the displacemnt of oil from the shaft entering the shock body. The added oil of the res is just a byproduct of what its main job is. You can easily build the res onto the end of the shock also, as we do with the Radlo coilovers or Bilstein shocks. Making the res remote will make the working part of the shock shorter. There are shocks that allow the oil to mix with the nitrogen, these are emulsion shocks. They can work well but dont offer the consistency and over-all performance of a remote res shock. Emulsion shocks leave a space at the top of the shock for the oil to compress. They can only be mounted one way as the piston will go into an air pocket if mounted upside down.
Part 2, nitrogen charged shocks are not related to an air shock. The nitorgen pressure only acts on the shaft diameter. For example, using a 5/8 shaft Radflo or Fox, with 200 psi of nitrigen at full extension will be about 61 lbs of force (called NOSE pressure). Assuming the dividing piston is near the hose end of the reservoir and its a 10" travel shock, the nose pressure at full comprssion may be 70lbs. The piston in the res only moves about 1.25 inches because that is all the oil the shaft displaces. Again, not an air shock at all. This number does not contirbute to spring rate but may lift a vehicle slightly. Look at it as removing 61 lbs from the weight of the vehicle as a change in ride height.
Part 3, nitrogen pressure is directly related to shock valving. The more weight, more valving, the more pressure required to keep from cavatation. Inside the shock is a piston with shims that are stacked kind of like how a leaf spring is set-up. There are shim stacks on both side of the piston, one to control compression the other side controls extension or rebound. This piston is in a column of thin hydraulic fluid. The fluid is forced to go through ports or holes, and then push against the shims. How much resistance you design into these stacks will determin the performance of the shock and, consequently, how much nitrogen pressure is needed before cavtation begins. Pressures can range form 50 psi to well over 400 psi. Typical pressures are in the 200-300 range. Some race shocks and most bypass shocks run the res. hose on the rebound side of the piston (out the bottom of the shock body) becasue the pressure is always less and more consistant on extension. But you can not mount a coil spring on a shock set-up this way. Also by mounting the res on the rebound side of the piston, you can gain up to 15% damping do to not having the oil displaced from the shaft.
To sum it up the res. is way of making a performance shock shorter, or adding more oil capcity for potentially more cooling. The problem is that the res hose (and its fittings) is typically a huge source of generated heat (more on this later).
This thread is not about shock tuning at all, I will save that for another thread.
Im not too computer savy, but im sure someone can post pics of what im taking about. Or find an exploded veiw of a shock.
 

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Excuse an ignorant question...but why can't you mount them piggy-back style with a shorter hose? That's what I did on my cherokee. Is it just too tight? Also I noticed that there aren't any bumpstops. Are you upgrading to hydraulic ones? If so I'm really curious about pricing and options. P.S. I live in Salem, OR and went to Winchester Bay last weekend. Sweet!!!
 

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Discussion Starter #14
ORXinOR said:
Excuse an ignorant question...but why can't you mount them piggy-back style with a shorter hose? That's what I did on my cherokee. Is it just too tight? Also I noticed that there aren't any bumpstops. Are you upgrading to hydraulic ones? If so I'm really curious about pricing and options. P.S. I live in Salem, OR and went to Winchester Bay last weekend. Sweet!!!
Alright... another Oregon boy.

There's no room to mount a resevoir to the shock body on the passenger side, regardless of hose length.

You could probably mount it to the shock body on the drivers side, however, you'll need a shock with the resevoir hose nozzle pointing the opposite direction (pointing the same direction as the passenger side, again because only one of the two shocks you receive will fit in the passenger side). Usually when you get your shocks the hose nozzle will be pointing in opposite directions, which really doensn't make them interchangable if space is an issue.

I just realized that the paragraph above isn't all the clear. I'll try to get some pictures posted...
 

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Discussion Starter #16
Yes you are correct. Passenger side mounted res. piggyback style on a FRONTIER!

I wish it where that easy with the Xterras. You would assume that with the same frame, everything would be exactly the same, as far as crossmembers and mounting points. But it's not. Take a look under the next X you come across.

Sweet set-up, though.
 
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