Build your own (cheapola!)
boost gauge, by John Altom
First, buy one of the cheap
($12US) tire gauges with the large dial and the attached hose.
DO NOT get one of the low pressure gauges that only reads up to
15lbs! Trust me, you will blow it up! Next, buy a 6-7ft length
of vacuum tubing at your local auto parts store. Also buy a
T-fitting to match the tubing size (3/16ths) Sorry guys. I
don't know metric. If you can find some of the small clamps
for vacuum tubing, consider yourself lucky! I used zip ties for
my project. If the gauge is a Victor brand, you will have fun
removing the hose. Use Vice-grips to crush the metal piece that
the hose goes into. NOT the piece that goes into the gauge!
You can pull the hose out of this piece with pliers. You will
want this piece completely removed so that you have the gauge
with the fitting sticking out ready for a hose to be attached.
At this stage, you have to make a decision. Do you want to have
your gauge show the boost and then return to zero or do you want
it to hold the reading until you release it? I personally
prefer to have it hold because it is very hard to look down
while you are on a high boost run! After the run, I just look
down and then release it after I see the reading. If you don't
want this feature, unscrew the metal piece that the hose was
attached to from the gauge very carefully. There are small
parts inside you can lose easily. There is a spring and a white
piece of plastic and a black piece of rubber. Take these out
and save them in case you change your mind later. The rubber
goes against the inlet then the plastic then the spring with the
small end against the plastic piece. Without these the gauge
will rise then fall back just like a regular gauge. You will
have to remove your seat, tank and battery. I would recommend
waiting until you are about out of fuel to make it easier to
handle the tank. Once you have removed these items, locate the
factory boost sensor tubing. It is on the back of the surge
tank and it looks just like vacuum tubing. While you are in
there, it would be a good time to check the sensor mounting
bushings. They are the rubber mounts that hold the sensors to
the back of the surge tank. If they are broken or dry-rotted,
call you-know-who and order new ones. Separate the hoses and
install the T-fitting so that one end and the middle are
reconnecting the factory hoses and the other end is
open. Attach the vacuum tubing you bought to the open end.
Clamp or Zip tie the hoses to the fitting. If your bushings are
ok, run a zip tie around them after you put the sensors back to
insure they don't come off. Route your tubing along the
underside of the backbone of the frame and use zip ties along
the way to keep it from coming loose. Run it up and around the
back side of the instrument cluster to the left side of the
gauges. Before you cut off any excess tubing, make sure you
have enough at full left and right steering lock! Attach the
hose to the connector on the "boost gauge" and clamp or zip tie
it in place. I used zip ties to hold the gauge between the
clip-on clamp and clutch but, if you have access to a better
system, use that. Another thing I did was to spray it with
"Ignition Sealer" spray. You should be able to find it at any
auto parts store. Make sure you put something such as a round
piece of tape over the lens of the gauge this will keep the
spray from covering the lens and making it difficult to read
but, don't cover the seam between the lens and rim with tape.
This will help keep out moisture. If it does get wet, don't
worry, most of the parts inside are brass. The lens will fog
but, will dry out in the sun quickly. There you have it. The
total cost is around $15US. It's not perfect, but, it gives you
an idea of your boost for next to nothing and when you decide to
buy a real gauge, you already have the tubing ready to hook up!
