I've researched nitrous on and off over the years, and have decided to go for it. All I want is a modest horsepower level (50 - 75 HP) for the occasional extra bump in power. I have decided to go with a nitrous express single nozzle EFI wet kit, with a fuel pressure cutoff switch, as well as rpm window switch, and a tune. Nothing novel about that setup, but I was thinking about doing something a little different to make things a little "safer".

I was thinking about using an AEM WideBand Failsafe guage to shut the entire nitruos system off if the system goes to lean. My plan would be to add one addition relay (normaly closed) as the first component in-line with the nitrous wiring. This way, under normal conditions the relay isn't activated and voltage flows normally (essentialy, the relay is doing nothing), on to the nitrous arming switch and rest of the sytstem.

I would then ground this signal circuit of this additional relay through the low side output of the AEM wideband and program it to enable the low side output (provide ground for the signal circuit of the relay) when the AFR hits say 13.7 (just a random number i picked). This would open the contacts of the additional relay I installed, breaking the circuit, and cutting off voltage to evertyhing else in the nitrous system downstream.

I also even thought about wiring the AEM gauge in parallel after the nitrous arming switch, that way the wideband is only working when I flip the nitrous arming switch. This serves no real purpose other than the fact that I don't have to look at the dancing LED lights of the wideband gauge on my A-pillar under regular non-nitrous use. It's not like I really need to monitor my AFRs under daily driving with my basic bolt on mods.

What do you think? Obviously, it is an extra cost, the gauge isn't cheap but I currently do not have a wideband and kind of wanted one anyway. I also wonder if this gauge will react "fast enough" to actually prevent any damage. It just seemed like an extra guard against a stuck open nitrous solenoid or if a fuel solenoid doesn't open. Just thinking out loud, what do you think?

 

I have been using nitrous on my s2k for 2 years! 75 shot is the best for the street imo! Anything u need to know ask me. Wide band is a must so u can tune it with jets or if u have an ems.

 

U have way to many elecronics in mind. Micro switch and a toggle is all i need. Fuel pressure gauge on my rail along with a walbro 255 in the tank. Bottle warmer and a wide band, easy to diagnose if u ever have an issue. My kit is all mechanical with just a toggle to arm the system and a micro switch mounted under the gas pedal backet.

 

Yeah, maybe all that stuff is overkill, but I like messing with stuff like that, the more gadgets the better :-). I also did some more research on the failsafe gauge and it looks like a useful tool even if I don't use it to turn off the nitrous the way I mentioned above, there are other things I could use it for.

2 questions for you.....

Are you still running the stock clutch with that 75 shot?

What spark plugs are you running?

 

You can control all of that through an aem ems. Just get that to tune it with. They do not have lean protection built in right now, but it is coming in their next software release. The only other thing you will need is a wideband.

 

You can buy a lean shutdown switch which does exactly what you were talking about.

Also if you want a full zex nitrous kit with all the gadgets (minus the lean shutdown switch bc I didn't use one) hit me up and I can make you a deal as I'm planning on boosting

 

I replaced my stock clutch at 136k just cause i had the chance. I'm using a CC pressure plate with an act 6 puck sprung disc. I am running one step colder ngk's and i usually run it with 110 leaded gas. But pump gas works great too.

 

Stock clutch only slips when u shift it fast into gear. But it holds the 75 shot in every gear no slippin at all.