NITROUS OXIDE ( nos / n2o ) advice forum

Hello all, I have an issue that I hope I can get some help with, first I will list my build.

2007 Mustang GT
298 livernois stroker with stage 3 heads
ID 1000 injectors
Division X Return style fuel system (1200 horse)
D1SC Procharger with 800 horse stage 2 upgraded intercooler with a 3.400 pulley (20 PSI at 6500 RPM)
E85

Car made 650 to the wheel on the blower alone

Before the blower, the car was a nitrous build, and I still have the nitrous kit on the car, it had sat dormant for the last year as I played with the new blower. My kit consists of,

Custom Nitrous Outlet direct port, currently jetted for a 75 shot (18/10)
NX SAFE standalone fuel cell set at 50 PSI (Using E85 as well)

Now before the blower the kit was jetted for 200 shot and worked great for 2 years. I put hundreds of pound of nitrous thru the car with zero issues, of course that was N/A. The problem started the other day when I tried to spray the 75 shot on top of the blower.

Window switch is from 3500-6800 controled by a wotbox. I logged with just boost and everthing was fine, so I loaded my nitrous tune and hit it, It has a bad lean spot from 3500 to 5000 rpm.

The hit felt great, but i lost 1 or more plugs in the pull, I had to change out all 4 plugs on the drivers bank to get the car logging correctly after the pulls as it was showing bank 2 o2 sensor was not happy, I had a ton of unburnt oxygen in the charge. SO I just replaced all 4 plugs and the car is happy again...and I have not sprayed the car since.

Now i will say that the regulator was not boost referenced on the nitrous pulls. It is now, but it was not during my first test hits.

I called 2 reputable nitrous companys and asked them what they thought of me going lean.

Company 1 response

Fueling is always an issue to get correct when compounding nitrous with boost, suggest you up your fuel pressure and install your 200 horse fuel jets (16) and see what it does. He went on to say that a pressurized manifold will NOT affect jetting in a situation like this....

my thought is then why do I need to up my fuel jets?? Not happy with this response I called Nitrous company 2

Company 2 response.

Boost reference your stand alone fuel regulator...done! Manifold pressure DOES affect jetting so if you have 50 PSI fuel pressure and manifold pressure is 20, you are only delivering 30 PSI of fuel pressure into the stream.

This theory makes more sense to me, but I would like to hear form some guys in here that have real world experience wit this.

As my car sits, I'm still jetted for 75 and i have increased my fuel pressure to 63 and have boost referenced the regulator. I want to go make a test hit but am going to wait until I read some replies in here before I do...

Am i putting too much science into this? Does manifold pressure play a part in jetting?

Thanks for any input anyone can share.


Engine



Nitrous Kit



Bench testing fuel jets. .010 jets at 50 PSI.

http://vid864.photobucket.com/albums/ab ... duuzqm.mp4

As long as you're jetting is correct and you're regulator can sense the manifold pressure changes, then you should be able to test the system. However, take very special care and read your spark plugs to look for any signs of nitrous distribution problems (and certainly other problems) because they most certainly exist with this nitrous setup.

I'd dump that setup before making any more power.

All the above reply (by one of my AMERICAN customers, who has converted from homeland brands to WON), is CORRECT!!!

I'd also add that anyone who tells you to jump back in at 200 HP immediately after suffering ANY kind of problem is to be IGNORED.

I'd also suggest that although your engine MAY 'APPEAR' to be OK now that you've replaced the plugs, there is a HIGH PROBABILITY that you are actually now on the route to SERIOUS ENGINE FAILURE. When a plugs melts, some if not all of the molten metal, USUALLY gets trapped between the exhaust valve head and and the seat, which causes a small degree of leakage (loss of compression). Over a relatively short period of time the areas where the metal is trapped will burn away and the leakage will worsen, leading ultimately to burned out valves/seats and damaged pistons.

There are only 2 ways to determine if you've been EXTREMELY LUCKY;
1) Carry out a LEAKDOWN TEST (NOT a compression test), although that MIGHT be better than nothing and MIGHT show up a loss of compression compared to the cylinders that didn't melt a plug.
2) Have the cylinder heads removed and the valves/seats inspected

Taking these steps NOW will at very least give you some peace of mind and may very well save you a HUGE amount of money later.

Final point, a CORRECTLY DESIGNED & CORRECTLY FITTED nitrous system would NOT cause a lean condition for any period of time.

thank you for the reply's

To be clear, I didnt melt any plugs. I logged the nitrous hits and after them, bank 2 o2 sensor was reading high oxygen which was causing my wideband to read lean. So I changed out my plugs on that side and that corrected the issue.

As for the video, yes I was just looking for blockages as the .010 jet is very small.

When I had NO build me that kit, I told them I wanted a 200 horse kit. i paid good money for it and Im getting the feeling here that it is sub par in some ways, im guessing there are not enough solonoids?

Seeing how I ran this set up with a 200 shot for so long I thought it could support a 75 shot without issue. Im willing to do whatever it takes to redo this set up to make it work...just upsets me a little to hear that it could have been built better.

Boost is fairly new to me and spraying on top of boost is only 4 days old for me as well.

Attached is a datalog for a WOT 3rd gear pull with a window activation at 3500, you can see the lean spike, but then up top it looks like it corrects itself...very weird.

I'm very pleased to hear that you didn't melt any plugs, as that saves you from all the trouble I mentioned.

For your future reference, when a plug ceases to perform (not melt) we use the term "a plug went down" and we use the term "lost a plug" when one is melted (or broken), just to avoid any future potential misunderstandings.

Alex (Turbobox) has once again answered all your points absolutely correctly, so I don't have to add much.

I'd like to expand on;

1) The cause of the lean spike (which as Alex states is as a consequence of an inherent FAULT in ALL nitrous kit designs and incorrect fitting), is also as a consequence of the difference in flow speed of nitrous and fuel. At 1,000 psi the nitrous travels much faster through the pipework, than the fuel at under 100 psi. The longer the pipe work and the larger its volume (from using over size bore pipe), the bigger the difference between the delivery times.
WON is obviously the only company in the world to appreciate this FACT (and do anything about it), otherwise other companies products would use more of the component designs, that are currently UNIQUE to WON.
The solutions to cure this problem are;
i) Only use components that are designed CORRECTLY
ii) Fit the system as instructed by WON
iii) Add a Max Extreme and utilise the nitrous only delay to totally erradicate any remaining differential in delivery time

2) Adding a 2nd set of solenoids would help to reduce the lean period, as that would shorten the pipe routes and reduce the volume. Although adding another pair of the same solenoids would help A LITTLE, you really need the whole front end Replacing if you want the very best results.

3) Boost - in addition to the comments made by Alex, I'd like to add that there are a couple of differences compared to NA use of nitrous;
i) A boosted engine will already be subjecting your ignition components to much greater load, so the spark is more likely to be inadequate and fail.
ii) Even NA you need the strongest possible spark you can get, so that's even more important on a blown motor
iii) When you add 200 HP to a NA engine you're very unlikely to see as much as a 200 HP increase at the crank but add the same amount to a blown engine and it could make much more , so you don't need to add as much nitrous to a blown engine to achieve a given increase.