NITROUS OXIDE ( nos / n2o ) advice forum

I was previously using NOS super pro shot solenoids on my pro-mod bike and was having trouble launching at Shakespeare county raceway (Shakey). You see I couldn’t reduce the nitrous start power enough and kept lighting up the slick off the line. I knew of Noswizard’s experimental smoooth system but couldn’t afford to wait for production; I needed a quick fix right away. After a chat with Noswizard we agreed that a pair of 150bhp pulsoids running in parallel would have the response and throughput I required, so I bought a pair ready siamesed together that I could just bolt into my current system. My nitrous system has a pressure sensor on the output of the solenoid/pulsoid so I can see the results of the progressive output. With my smallest jetting and a progressive setting of 20% to 100% over 5 seconds the old system would hit 100% after 0.4 of a second. However, the twin pulsoid system ramped up almost exactly as defined. As is always the case in racing, other problems have so far stopped me realising the full benefit of the new system. But to date it has allowed me to double my nitrous power, increase my terminal speed from 177mph to 186mph, and improve my elapsed time over the quarter mile from 7.35 to 7.16 seconds. As soon as my large hammer has cured the other problems I’ll be in the 6’s and 190’s!

I am a neutral observer, however, I do have a lot of experience with NOS, NX and now HPS. I currently have my HPS nitrous kit up to 200Hp and will bring it up to 300 this week in a streetable car.

The biggest thing and I still cannot get over it is the soft hit of the nitrous. It is so deceiving. There is no sledge hammer bang to the drive line, but, there are massive amounts of torque that seem to come in seemlessly, even when running a fixed stage of 200 hp.

If anyone want some new NOS solenoids, I can make you a good deal on them.

IAT2 temps & EGTs were nearly identical on and off nitrous.
The maximizer was set to ramp up the shot size from 50% to 100% over a 2 second timeframe. I honestly could'nt tell it was working til I was pulling up through 3rd gear where it just felt stronger. That maximizer makes this thing so smooth that there was zero traction problems.
Also, I had the maximizer set to shoot the fuel first so I'd not get the initial lean out that I hear is quite common with fixed hit systems.
Rich

I have been working and testing a progressive nitrous controller for a school project. Myself and my partner are using a set of NX solenoids that we had laying around and have found some interesting things. The NX solenoids if pulsed over 20Hz cannot respond fast enough because of their inductance the solenoid itself actually ramps open and closed but most of the time will never fully open or close. After we figured out how to deal with this by pulsing the system slower we found that you need to pulse your fuel at a much higher duty cycle since fuel is an incompressible liquid while the nitrous is not. When the system was pulsed at 50% we have very near 50% fuel flow it was closer to 55 which was within spec as far as we were concerned. The nitrous on the other hand was flowing nearly 90% of the flow. As far as we can tell so far it's line from the solenoid to the jet that is the problem. The difference between the outlet orifice of the solenoid and the much smaller jet makes the line act as a reservoir so the pressure in the line just builds and builds which makes the nitrous flow at a much higher rate than is wanted. What we are working on now is a way to move the jet to either the feed side of the nitrous solenoid so there is effectively no place for a reservoir or move the jet very very close to the solenoid. I don't know if anyone has checked their systems to see if their wideband shows lean conditions on the ramp up. Just some information I thought I would pass along.