I would like to start by giving credit to StrangeBalla55 for the idea
and inspiration for this mod. Also I would like to say that there are
many ways to do this mod and this is simply my take on it.
On a stock shocker sft or nxt the solenoid tube's flow is limited by
the tiny hole that is found under the va.
The hole being that small does serve a purpose though, as it limits the
amount of air that can be stolen by the firing chamber during rapid firing.
The trade off to this
restrictor hole is that it also limits the flow into the solenoid. The
idea behind this mod is to creat a small check valve(1 way valve)
inside the left insert tube that will allow air to flow into the
soleniod chamer but not back out of it. This will in turn let you dill
out or enlarge the solenoid hole, which will give you more consistant
cycles at higher rates of fire. For this walk through I have chosen to
to keep the solenoid filter as that is not a choke point for the air
flow to the solenoid and it keeps the solenoid clean.
1) First you take the left solenoid insert out of your shocker and remove
the filter screen from the front of the insert.(Don't damage or distort
the screen when removing it.)
2) Now you need to make the valve seat. For this I went to ace hardware
and bought a .23 OD rubber well nut. It is basically a rubber tube with
a threaded brass insert inside. Once you have the rubber tube you need
to sand ot turn down the outside diameter by about .020"(with the final
OD being .210 )in order for it to fit good in the shocker insert tube.
Then cut the rubber tube in half right after the threaded brass insert
so you are left with a little piece as shown.
3) Next we need to make the piston. The od of the piston should be around
.185" and at least .4" from end to end(including taper). I went with a
golf tee as it was the correct OD and it was already correctly tapered
at the end. Optional: I put some shallow grooves down the side to help
flow a little. Just make sure not to go too deep, or cut into the
sealing face on the piston.
4)Now take a the remaining peice of golf tee and make a spacer to hold
the valve seat from sliding forward and shutting off the air.
You will also need either a very small and soft spring or a set of
small rare earth magnets(radio shack). If you are using magnets glue
them to the end of the piston and the solenoid filter so they are
opposing. I ground douwn the OD of the magnets slightly so they would
fit better in the insert tube.
This is what you should have so far.
5) Now you need a 6-32 threaded rod that is at least 10" long. I found
this at ace hardware as well. Next wrap tape around all but the last
.3" of threads so you dont scratch the body during installation.
6) You need to set the correct gap between the piston and the
solenoid filter by cutting the filter shorter until the spring or
magnet puts just enough pressure on the piston to keep it from shaking
around freely in the insert tube. Note that if you are using a spring
that you can also cut the spring shorter to help get the right tension.
7) Finally drill/mill out the solenoid hole on the body larger. You can drill extra holes like there are for the right insert tube, just be careful not to cut were the oring seals.
Slide spacer thicker side up into the left solenoid tube. Then thread the valve seat onto the threaded rod and slide it into the left insert tube until it bottoms out against the spacer.
Now drop in the piston in the left insert tube.(followed by the spring if your using one). Lastly screw in the insert into the body to the right depth and you should be ready to rock.
This is what the completed ipr should look like outside of the body.
Disclaimer- This walkthrough is for informational purposes only, I am not responsible for messing up your shocker if you should attemp this and break something.