- Joined
- Apr 15, 2006
- Messages
- 22,638
- Reaction score
- 20,532
- Points
- 113
- Location
- Sth Auck, NZ
- Members Ride
- HSV VS Senator, VX Calais II L67
If you read the instructions from a big supplier like NOS they will say that for most engines a 50 shot (wet shot) is safe, just run good fuel. A cooler plug and smaller plug gap also won't hurt to ensure the ignition doesn't misfire.
Using nitrous or any other form of forced induction increases how much air (and conversely fuel) enters the cylinder. More air/fuel = a bigger bang (this is one of those internet falsehoods as there isn't a bang but rather a controlled burn but we'll leave that for another day) which means higher cylinder pressures. For this reason nitrous kit instructions will tell you not to use nitrous under a certain rpm (normally about 3000rpm). I'm not going to go into the technical details as it will take pages and pages but if you want to run more than a 50 shot most manufacturers will tell you that for every 50 hp of nitrous you need to retard the ignition timing 2 degrees. More nitrous will also need a cooler plug and a smaller plug gap (higher cylinder pressures) which will make it harder for the ignition to create a spark. A dropped spark when nitrous is been used is very dangerous and is one reason nitrous has a reputation for killing engines. Nitrous doesn't kill engines, the miss use of nitrous kills engines.
Obviously if you are going to go for a bigger nitrous shot than forged rotating assembly becomes more important.
You will also find most standard jetting on kits jet the mixture rich, i.e more fuel. Much like your regular engine tune, more fuel effectively cools and slows the burn rate in the cylinder. they do this to make it reasonably safe. Once you have a baseline with the standard recommended jets then you can start tuning the nitrous (remove fuel or add nitrous to lean it out) but you need to be able to read plugs and understand engine tuning to start chasing power.
To me, the biggest things with nitrous is ensuring a good fuel supply (you really don't want a lean out with the nitrous on) and running a fuel filter before the fuel solenoid.
Nitrous really is interesting stuff, liquid supercharging if you will but it requires just a little knowledge. Heaps of info out there though.
Nitrous kits traditionally use jets to regulate how much nitrous and fuel are injected into the motor (wet shot). More modern systems actually pulse the solenoids (much like fuel injectors) to allow you to use a small amount of nitrous at low rpm and then increase to full flow and engine rpm allows (and you don't blow the tyres off).
Dry shot nitrous systems only inject nitrous and then relies on the cars fuel system to add the extra fuel required (not normally possible on a regular engine management system or carburettor).
Using nitrous or any other form of forced induction increases how much air (and conversely fuel) enters the cylinder. More air/fuel = a bigger bang (this is one of those internet falsehoods as there isn't a bang but rather a controlled burn but we'll leave that for another day) which means higher cylinder pressures. For this reason nitrous kit instructions will tell you not to use nitrous under a certain rpm (normally about 3000rpm). I'm not going to go into the technical details as it will take pages and pages but if you want to run more than a 50 shot most manufacturers will tell you that for every 50 hp of nitrous you need to retard the ignition timing 2 degrees. More nitrous will also need a cooler plug and a smaller plug gap (higher cylinder pressures) which will make it harder for the ignition to create a spark. A dropped spark when nitrous is been used is very dangerous and is one reason nitrous has a reputation for killing engines. Nitrous doesn't kill engines, the miss use of nitrous kills engines.
Obviously if you are going to go for a bigger nitrous shot than forged rotating assembly becomes more important.
You will also find most standard jetting on kits jet the mixture rich, i.e more fuel. Much like your regular engine tune, more fuel effectively cools and slows the burn rate in the cylinder. they do this to make it reasonably safe. Once you have a baseline with the standard recommended jets then you can start tuning the nitrous (remove fuel or add nitrous to lean it out) but you need to be able to read plugs and understand engine tuning to start chasing power.
To me, the biggest things with nitrous is ensuring a good fuel supply (you really don't want a lean out with the nitrous on) and running a fuel filter before the fuel solenoid.
Nitrous really is interesting stuff, liquid supercharging if you will but it requires just a little knowledge. Heaps of info out there though.
Nitrous kits traditionally use jets to regulate how much nitrous and fuel are injected into the motor (wet shot). More modern systems actually pulse the solenoids (much like fuel injectors) to allow you to use a small amount of nitrous at low rpm and then increase to full flow and engine rpm allows (and you don't blow the tyres off).
Dry shot nitrous systems only inject nitrous and then relies on the cars fuel system to add the extra fuel required (not normally possible on a regular engine management system or carburettor).
