nitrous theory inside

100 shot @ 6200 rpm adds 100hp/85ft-lbs
100 shot @ 5252 rpm adds 100hp/100ft-lbs
100 shot @ 3000 rpm adds 100hp/175ft-lbs

150shot @ 6200 rpm adds 150hp/127ft-lbs
150shot @ 5252 rpm adds 150hp/150ft-lbs
150shot @ 3000 rpm adds 150hp/262ft-lbs

200shot @ 6200 rpm adds 200hp/169ft-lbs
200shot @ 5252 rpm adds 200hp/200ft-lbs
200shot @ 3800 rpm adds 200hp/276ft-lbs
200shot @ 3000 rpm adds 200hp/350ft-lbs

Is it the torque or the hp that kills the motor when you spray too much? If it's torque, couldn't you just spray it at a higher rpm as to reduce the amount of torque? For instance, if you can safely spray a 150shot at 3000rpm+, wouldn't it seem ok to spray a 200shot at 3800rpm+ ?

I don't think that's just theory, it's absolutely true though maybe your numbers are a bit different than mine would be. Think about it another way too:

For your 150hp@3000rpm scenario: During each revolution, each cylinder sucks in an amount proportional to 150/3000 worth of nitrous/fuel mixture and explodes it.

For your 200hp@3800rpm scenario: During each revolution, each cylinder sucks in an amount proportional to 200/3800 worth of nitrous/fuel mixture and explodes it.

150/3000 = 0.05
200/3800 = 0.052
200/4000 = 0.05

So I'd say you break even if you run a 200 shot at 4000 + RPM

This is why people use multi-stage nitrous systems, or even computer controlled gizmos to gradually increase the nitrous amount as the RPM's go up. Well, in addition to being able to keep the tires stuck to the ground.

Dave

Originally posted by juiced_lt1


Is it the torque or the hp that kills the motor when you spray too much? If it's torque, couldn't you just spray it at a higher rpm as to reduce the amount of torque? For instance, if you can safely spray a 150shot at 3000rpm+, wouldn't it seem ok to spray a 200shot at 3800rpm+ ?


somthing like that.


its really the cylinder pressure. like you have shown, you're spraying a constant amount of air and fuel into the motor... but at lower RPMs, the pressure can become insanely high... high enough to break stuff.


what your saying about the spray pressure is true to a point... thats where a RPM based progressive controller like the jacobs nitrous mastermind is nice.

Good question Lee, this is definitely an interesting topic.

Mr. Dude has the correct answer. In fact, the additional cylinder pressure from nitrous is in a direct inverse proportion to rpm. Same nitrous shot at X rpm produce twice the addtional cylinder pressure as at 2X rpm. The other reason for staged or progressive systems is to help with traction.

Rich Krause