Nitrous Questions

[pw_Tony]

A true statement indeed.
The other thing Tony needs to know is to learn to read the plugs after a good Nitrous pull and run the system alittle rich on the fuel side. It might take a little hit out of the system but 10-15% rich is better than 10-15% lean.
Sleeper
OK Will diffentely checking out the plugs after some pulls, starting out with a 125 shot first, but I'm sure nitrous is like a blower, it's too easy to get more power so we might get greedy:devil:

[DUCKY]

Just a few quick suggestions.
#1, Bottle pressure.... 900-1000psi Excessive bottle pressure increases nitrous flow and makes for a lean condition which is a bad thing....
#2, Fuel pressure safety switch is absolutely required. A separate fuel system (pump, filter, etc.) for the N20 system is not a bad idea either.
#3, Pressure regulator and gauge on the fuel side of the N20 system for fine tuning. Start out with at least 10psi for safety and lean it from there based on plug readings. A bypass type regulator right next to the fuel solenoid is the best setup. This prevents an air pocket from forming next to the solenoid. N20 without fuel = KABOOM
#4, Nitrous Retard from MSD...a good thing.
#5, Fuel should be high quality. NO PUMP GAS, at least for the N20 enrichment.
#6, Keep it rich. Nice light brown colored plugs with the timing line out towards the edge of the ground strap means safety. Clean white plugs with timing lines up towards the threads means you are playing with fire.....
Hope this helps.....

[pw_Tony]

Just a few quick suggestions.
#1, Bottle pressure.... 900-1000psi Excessive bottle pressure increases nitrous flow and makes for a lean condition which is a bad thing....
#2, Fuel pressure safety switch is absolutely required. A separate fuel system (pump, filter, etc.) for the N20 system is not a bad idea either.
#3, Pressure regulator and gauge on the fuel side of the N20 system for fine tuning. Start out with at least 10psi for safety and lean it from there based on plug readings. A bypass type regulator right next to the fuel solenoid is the best setup. This prevents an air pocket from forming next to the solenoid. N20 without fuel = KABOOM
#4, Nitrous Retard from MSD...a good thing.
#5, Fuel should be high quality. NO PUMP GAS, at least for the N20 enrichment.
#6, Keep it rich. Nice light brown colored plugs with the timing line out towards the edge of the ground strap means safety. Clean white plugs with timing lines up towards the threads means you are playing with fire.....
Hope this helps.....
So 91 octane is a no no correct?

[ULTRA26 # 1]

So 91 octane is a no no correct?
91 octane with enough fuel, in the mix, shouldn't be an issue with a 125 or 150 shot. Great advice from many so far.

[QuickJet]

Running a 10.5-1 compression small block with a small cam plus 150 shot and only using 91 octane to do so is asking for trouble. Especially for a first time go at it.
I'd run 100 octane minimum with that combo (and that's only with a dedicated fuel system for the nitrous). I'd run a separate tank, fuel pump and regulator just for the nitrous system. Run a fuel pressure gauge and a low delivery automatic cutoff. Regulate the fuel delivery between 5.5 and 6 psi
Stay away from large gaps and extended tipped plugs as well. With the 150 shot I'd run 1 stage colder plug and pull about 3-4degrees total out of the timing.
After each pass pull a plug to see where you are at with the settings. I always ran my nitrous settings a bit rich to be safe.

[Sleeper CP]

Someone wrote about a big gap....That would be a big NO No if you ask me.
Gap at 28 thou. to start with.
Sleeper CP

[hotbo]

all of this is good info,but imo dont get carried away with all the seperate fuel stuff,maybe big nos hits yes,but 300 or less imo not needed.nx express says to run no more than 5psi pressure to there nos kits,ive got my pressure saftey swithch set at 5psi and my fuel pressure iss at 7.5 so if it starts to fall below 5 its suppose to shut down. i have a digital 6 box msd that has a single single step retard so i can just turn the dial to whatever setting i want to retard my timing when i mash my button.ive ran 4 bottles with my 150 ive now stepped up to 200 and gonna try this.i havent had the slightest problem yet,key word yet,just watch your pressure and so forth read all 8 plugs after a good solid nos pull and see what they look like,oh yeah nos will clean your plugs off so you need to look down inside the plug not just the top part of the porcelian.hell at any given time a mill will frie with any kinda nos,boost.all you can do imo is just pucker yo ass and hope for the best.thats what i do. 150 or less they say run 93 octane,anything above this and run racing mix or full blown racing fuel.later trav.

[N281PONY]

Is this a brand new kit? If not I would go through the solenoids. Pull them apart and clean them. Maybe even put a new set of seats in them.

[HOWARD UFH]

all of this is good info,but imo dont get carried away with all the seperate fuel stuff,maybe big nos hits yes,but 300 or less imo not needed.nx express says to run no more than 5psi pressure to there nos kits,ive got my pressure saftey swithch set at 5psi and my fuel pressure iss at 7.5 so if it starts to fall below 5 its suppose to shut down. i have a digital 6 box msd that has a single single step retard so i can just turn the dial to whatever setting i want to retard my timing when i mash my button.ive ran 4 bottles with my 150 ive now stepped up to 200 and gonna try this.i havent had the slightest problem yet,key word yet,just watch your pressure and so forth read all 8 plugs after a good solid nos pull and see what they look like,oh yeah nos will clean your plugs off so you need to look down inside the plug not just the top part of the porcelian.hell at any given time a mill will frie with any kinda nos,boost.all you can do imo is just pucker yo ass and hope for the best.thats what i do. 150 or less they say run 93 octane,anything above this and run racing mix or full blown racing fuel.later trav.nitrous doesnt blow motors up trying to side step the dedicated fuel system would. 300 shot warrants a dedicated fuel system.I dont think you should be crossing your fingers every time you are in the button just my personal experience

[Boostedballs]

Separate fuel tank with its own pump and regulator. Your "ARMED" switch can turn the pump on and the throttle can activate the solenoids at WOT and ONLY WOT. Good race gas or AVgas is good to have in the nitrous fuel tank not just because you have a high compression engine but because you won't have to drain it if you leave your boat sitting or you don't use the NOS very often. Shelf life of pump gas= 2 weeks; shelf life of AVgas= 2 years.
I would start with the medium fuel nozzle and the small N20 nozzle. Bring a couple sets of plugs with you and shut down right after a N2O run. If you let your engine idle for a while it can change your reading and throw you off.
I would go with a SMALLER gap if any gap change at all. The higher the cylinder pressure, the more power is required to jump the same gap. N20 WILL increase your pressure.
Either way, you don't want to stomp the gas from an idle. I would go 3/4 throttle until your RPM's are over 3000 or so before spraying. You could buy an RPM activation switch for $.
Your piston will get out of the way of a good N2O combustion, even if it means it has to kick a rod out the side of the block. RPM is safety.