Fitting DIY Nitrous Kit:
More on Fitting Your Nitrous System!
Fitting N2O systems (NOS) to cars and bikes
Nitrous tank mounting and temperatures...
Nitrous oxide bottle
pressure is the Nitrous Oxides own vapour pressure. This is
the only thing that forces it into being a liquid. The
actual pressure is caused by the liquid trying to boil off.
Since its in a sealed container, it cant! This pressure is
around 800psi at room temperature. This is the key!
TEMPERATURE! The pressure in the bottle has little to do
with the amount of liquid Nitrous Oxide that's left in it!
As long as there is a
spoonful of LIQUID Nitrous left it
will read the exact same pressure as it does when it's
Now the actual bottle pressure is unimportant,
Since you can correctly jet the nitrous system to operate at anything from 600
to 900 psi. But the pressure variation due to cold/hot temperatures
alters the amount of Nitrous that gets delivered to your
motor. With consistency in mind, you will want to mount the
sources of heat. Exhausts, unventilated car boots and
interiors in summer time, engine bays, etc.
severe cold (Car boots get cold in winter too! That's
the reason for bottle heaters!)
of the above is contradictory... Common sense will allow you
to keep an eye on the bottles temp and pressure. But at
least you will keep in mind that obvious problems can be
avoided. Such as a part of the boot floor that gets
hot on a long run is a bad choice of place to mount your
bottle. And opening the lid when parked in hot sun will help
avoid problems! And expecting your nitrous system to work
normally after a icy winter morning where the bottles been
outside all not going to happen!
should be mounted with whatever type of secure bracket or
mounting you want to fabricate/buy, but it needs to be
orientated so that:
accelerate the pick up pipe inside the bottle
still picks up the Liquid Nitrous Oxide Gas from
the bottom! So generally the valve outlet needs
top point downwards, with the top of the bottle facing
the front of the car or bike and the "bottom" sitting
lower than the top. Anything from 10 degrees to
the horizontal up to and including vertically 90 degrees
upright is fine!
Whatever space and installation and
cosmetic appearance requires. Remember you will need to
remove it often to refill!
reasons of "prettiness" on motorcycles, people often
want to put the bottle in line with the tail piece or
seat unit with the valve facing forwards to keep in with
the general aesthetics of the bike. This is OK, provided
that you fit the pick up pipe inside the bottle so that
it ends about 1/3rg of the way along the bottom of the
bottle from the valve/bottom edge. But you will never
get all of the Nitrous out of the bottle as a result. No
problem if you refill or top up between runs at the
strip though! I used to do this.
metal bracket with Velcro straps, or rubber straps is
fine, or with long "hose" type clips provided it can be
easily removed for filling.
Once you have the
Bottle or Tank mounted you need to decide what you are going
to use for a pipe between the Bottle valve, and the Nitrous
solenoids. This requires a few decisions. One of which is
where to fit the solenoids - So read ALL this page before
a) Are you gong to use
NYLON 4MM O/D,
pipe? (Or if you are a real cheapskate you can
use 3/16ths solid copper brake pipe! - I did this on my
brothers V8 car - he was a poor student!) You need to decide
If its easily possible to run
the pipe INSIDE the car then this is the best and easiest
option remembering that HEAT is a problem! Keep away from
all heat sources. Sometimes you will be able to run with the
cars wiring loom, sometimes under carpets or inside the
plastic trim etc.
c) If the above is not
easily possible, or the route too long or torturous
(straight & short runs are MUCH better!) then drill a hole
near the bottle valve, fit a rubber grommet and route it
under the car. AVOID hot things like the plague! Heat causes
the liquid to turn to gas! That's bad. You don't want that
Solenoids - Positioning
Now you have the
bottle mounted, and the nitrous line run to where you want
to fit the solenoid valves. Requirements:
easily accessible for maintenance and installation of
jets for setting up.
located as close to the point of injection (injector?)
located in a spot that's cool, and protected from the
in a position that allows a short Nitrous Line to be
mounted securely in a spot that is not subjected to
vibration like directly on the motor.
spot is chosen then you are in a position to make up a
simple bracket or mounting plate. One really good spot on
cars is behind the panel at the back of the engine bay where
fuse boxes etc are normally located. Or towards the
top edge of the inner wing at the rear corner away from the
Once a spot
is chosen then install and connect up the Nitrous Line to
the Nitrous Solenoid.
the fuel to the fuel Solenoid
There are many types
and styles of fuel system and pressures. All that's
important is that the CORRECT QUANTITY of fuel is delivered
to the engine to suit the nitrous jet used!
On Bikes... See
Some may be gravity fed, others may need to be
pumped. This is NOT preferable, just a necessity if any of
the following statements happens to be true! If you DO NOT
need a pump just fit a TEE piece into the pipe that feeds
the carb(s) and connect a extra bit of petrol pipe from here
to your Fuel Solenoid. Fit spring type clips. Petrol leaks
a) You want more than 40/45BHP
increase? You need a pump. See car section below.
b) You have a fuel tank
that is NOT above the carbs? You need a pump but you must
already have one! It MAY be big enough already. See car
c) You're bike is blow-through
carb turbo, or fuel injected. You need a pump, already have
a pump, and it is likely to be big enough! See car
On Cars... See
More info to
the term NOS is incorrect as this refers to an specific
company (called Nitrous Oxide Systems, in the US)