Resources 

Subcategories

• 

  Nitrous HP, PPH and other Calculations

  Here we go! In this article I am going to group/provide all the nitrous knowledge I can for you. Some of this will be content stated by others online, a lot will be my own experience, and some may be new information to you. I hope you can learn something and if anything is missed send a message so we can learn as well. Thanks, Erik

  I will try to keep relative source files linked. I'm doing this fast so let me know of any errors.
  .
  .
  1)****Nitrous Usage****
  USE=(PPH/3.6)/1250*seconds used)
  1.2lbs=(540pph/3.6)/1250*10seconds)
  .
  .
  2)****PPH****
  PPH = Pound Per Hour
  PPH/3.6=HP
  1170 pph/3.6=325hp
  .
  .
  3)****Calculate Rough HP From Jet Size****
  HP=(Jet Diameter MM)^2*70
  0.062 jet in=1.5748 mm
  174=1.5748^2*70
  To convert to wheel hp apply your loss percentage, say 15% in this example would be 148hp to ground.

  This link can also be used for rough estimates on jetting. I have been using it for around 6 years now.
  http://www.robietherobot.com/nitrousjetcalculator.htm
  .
  .
  4)****Setting Flowing Fuel Pressure****
  -If you have a stand alone fuel system you must set fuel psi with it flowing. Multiple ways to do this, we will try to cover them all.
  **Direct Port**
  I normally flow on a 72 jet on most direct port setups 1200pph and less.
  **Plate and Single Nozzle***
  I normally flow based on the fuel jet used in the application.
  .
  .
  5)****Flowing a Nitrous Side****

  -Flowing on 10 seconds the calculations are as follows. Say it used 4lbs of nitrous in 10 seconds.
  10 sec x 6 intervals = 1 minute
  6 intervals x 4lbs = 24lbs of n2o per min
  24lb per min x 60 min = 1440 pph
  1440pph/3.6 = 400hp of nitrous

  -Reference section 6 for the nitrous to fuel ratio.
  -Flowing nitrous side means to take nitrous and flow through your actual system to find out how much nitrous can pass through in a specified time, then converted to pph. This will show you exactly what hp and pph a nitrous jet will flow.
  -Some people flow for 5 seconds and convert to hours, some flow for 10. Mathematically there is no difference, in real life the difference depends on head room and bottle pressure. Starting with a full bottle may actually flow less over 10 seconds due to drop in head pressure. You may end up with more consistent pressure over the entire 10 seconds with a lower starting pressure and fill amount. I normally flow a big system 2lbs shy on a 15lb bottle at 850 or 900psi.
  .
  .
  6)****Nitrous Spreads, Ratios, and Calculations****
  Direct Port.....7:1

  Dry Direct Port...12:1
  Plate..............8:1
  Nozzle............8:1

  Sources:
  http://smithtex.com/racing/fuelcomp.html