Need some advice on NOS

[M@r]{]

Ive been offered a second hand NOS kit for £150.  Now to say I know nothing about this is an understatement!

First off I want to know what are the advantages of NOS?  Or more importantly disadvantages?  Ive heard it mentioned that rather than use it for just producing a bigger bang â€" it can be used for extra cooling?  If this is the case does that mean turning up the boost?

Next what do I need to confirm is in the kit?  Anything I will need specifically for the FD?

Then fitting?  Is it a DIY job?  Or best left to a specialist?

[AshRX]

make sure its a wet kit and not a dry one

[Oedipus Rex]

there was a sticky somewhere about installing NOS on a rex. I\'ll have a hunt.

[Oedipus Rex]

http://www.rx7club.com/forum/showthread.php?s=&threadid=111605&highlight=NOS

thats not a bad link.

[Bobfish]

You want to make sure your using a wet kit. What is the brand of the kit? I personally wouldnt use anything other than a wizards of nos kit, but youll probably get on ok with an equivalent kit (independant solenoids for gas and fuel)

Tuning is VERY important. You need to first off make sure your fuel pump is more than capable of pumping enough fuel. Work out the flow rate through your injetor sizes (550 & 850cc/min standard at 100% duty) and work out the flow rate of the nitrous injection nozzles for the fuel. Make sure your fuel pump has enough pump to make at least 150% of the flow per min before you even install the gas. Next off, tune very rich with a low power setting. I.e aim for 9 or even 8 to 1 for a/f with a 25 shot of gas.

the most important thing with a turbo nitrous car is to WATCH YOUR BOOST. Nitrous cools air and makes it denser, so not only are you tricking your MAP based system by giving it much denser air than its used to, making it lean out (hence the car provides x amount of fuel for x pressure of air expecting a given temprature and thus given density of air, you are increasing the density of said air by supercooling it with -112 degree gas) you are also hugely increasing the flow through the engine, spinning the turbos faster and the wastegates on an RX are not huge as we all know.

Once youve got your A/f ratio and boost stable, you can start to lean it out closer and closer to 14 to 1, but id say the lowest you really want to go is 11 or 12 to 1, just to stay on the safe side.


There is NOTHING wrong with nitrous. There is such a common misconception that it blows up engines, but it doesnt. Bad tuning does. The fact is, a nitrous kit only adds more air and more fuel, which is exactly what a larger turbo/more boost and a mapping session does.

Be conservative with it, make sure you do it properly and make sure the car is up to it and youll love it.

[Bobfish]

By the way, fitting and tuning can be done at home, but its best to get a rex on the rollers with gas just to check the A/f because as we know, a tiny amount too little fuel or a little too much timing and ping goes your rotor.  No specialist stuff is needed for a rotary thoguh, any nitrous kit will do.

[Andy_k]

I have been running my twins on gas for a while now, no problems whats so ever. Its like having a single turbo in a bottle at the push of a button.

I can only recommend Wizard of NOS kits been using them for over 4 years now, 1 year on the rx-7.

I got my car mapped at Re:worx and at the same time i got them to check the AFR while on gas. After running 60hp jet i got just over 60bhp@the wheels. I have a progressive controller which will allow me to run more but that much kick is enough for me, seems like it wants to lift the front wheels in 3rd. Also make sure you have a good spark!(from the plugs) and that you go a couple of grades colder if you go over 60hp.


The only disadvantage is having to fill the bottle and it burns off all the old carbon deposits in the engine making it feel like new, so yuo want to keep using it.

As your not 100% sure on it i would just take it to re:worx. safest way.


Andy