Do's and Don'ts from the Wizards Of NOS

The Do’s and Don’ts listed below are in order of importance, ignoring any of these
very important instructions could lead to engine damage or worse. Items without
an *should be carried out before using the system. Items marked with a single *
particularly apply to power increases of 25% or higher and items marked with 2 **
particularly apply to increases of 50% or more. These figures are just general
guidelines and will vary from one vehicle to another, depending on size and
strength.

Do have your engine checked with a leakage tester (not a compression gauge) - 6%
is just acceptable but none should exceed 10%.
Do check the torque settings of head bolts/studs.
Do have your fuel system tested to make sure it will deliver the additional fuel (that
the nitrous system will require) adequately – if in doubt fit a high capacity pump.
Do use high octane fuel and even higher octane for increases of 50% and over. *
Do test your spark strength – anything under 15mm in air will cause poor results.
Do replace the existing spark plugs with one grade colder (harder). *
Do fit a set of high quality plug wires (HT leads) - IF applicable. *
Do replace the existing distributor cap and rotor arm – IF applicable. *
Do fit a high performance ignition coil/s. **
Do fit a high performance ignition system. **
Do retard your ignition timing 2 degrees for every 50 bhp. **
Do use only top quality oil. **
Do purge the nitrous system at night or when the vehicle is left unattended.

FOR MAXIMUM SAFETY - Do fit an Ignition Delay Unit (IDU) or an ignition kill switch to prevent the possibility of back fires that may be caused when starting an engine with a static nitrous charge in the cylinders.

Do not operate the nitrous system without the engine running at a suitable rpm in
an appropriate gear.
Do not start the engine if you suspect the nitrous system has been activated while
the engine was not running. Purge the nitrous from the engine by removing the
plug caps and cranking the engine over, or fit an Ignition Delay Unit (see proper
section in manual for more information).
Do not use the nitrous system when the engine is off load, other than for brief
period during a static test.
Do not leave the nitrous bottle valve open while the engine is not running.
Do not use any components other than those supplied with the system. Each
component is an integral part of the system and incorrectly matched or unsuitable
components may cause engine failure at worst, or may not produce the best results at least.


IMPORTANT NOTE: [color=red]Remember that any weakness in the original design of the
engine and transmission will be brought nearer to it’s limit when large amounts of
nitrous are used. Therefore it is advisable to strengthen any such known weak
components before too much power is added. It would be impossible to give
details for every vehicle as to exactly what mods will need to be carried out and at
what % increase. However we can say one thing for certain: the more power that
you want, the greater the need to make modifications. The areas that may need
modifications are: fuel system, ignition components (as listed above), head gasket, pistons and clutch.

Quoted from the Wizards Of NOS website