Nitrous Yes or No ?

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Duster Drag Car said:
well i installed the sniper nos kit with a .055 n2o jet and a .061 fuel jet according to the chart on the holley nos site this should be a 125 hp shot at wot, not sure if ill use it, surly not until car is dialed in and im getting all i can get out of the motor naturaly asperated ,then ill try the nitrous and see how much it lowers my et.
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Way too rich. Depending on your fuel pressure (should be 5-6 lbs) I would start with a 55 n2o jet and no larger then a 55 fuel jet.
 
Some things to remember also is use of a colder plug, bottle pressure is huge as it will change your hp of the hit.

As you can tell from my signature the old dart with a small motor loved a little squeeze...
 
Like someone else said near the top of the thread...you should have your rings gap set for N2O. Nitrous motors need more ring gap than NA engines do. Other needs: strong spark, plenty of fuel volume at the correct pressure.

The “which is safer, rich or lean” thing…I say make sure it’s tuned properly and you won’t have to find out. In my experience, I always set mine just a little on the rich side for safety, this is why. N2O is an oxidizer, it is happy if you feed it enough, but if you don’t it will keep eating whatever it can to stay “happy”…like your spark plugs if you are lucky, or your pretty aluminum pistons if you are un-lucky. Keep a close eye on your spark plugs (watching for signs of detonation) and you should be fine.

When folks refer to rich being a problem with nitrous, they usually are referring to overly rich or excessively rich conditions (which is also a recipe for disaster with N2O)...like having fuel ignite where it is not suppose to (bye bye ring lands :-D).

Be safe, and have fun....and definitely get the car running right before spraying it.
 
Call Monte and ask him.

The instructions for 30+ years were so fat on the fuel side it wasn't funny. We used to alter fuel pressures so low to make them run right before the advent of jet pills.

Fat is worse than lean IMO. Fat will continue to run as shrapnel flies out the exhaust. Lean will usually barf and stop running. A lot fat is BAD! A little either side of optimum, likely won't hurt parts as long as you stay away from the "D" word... detonation.

MY 2 cents... pull at least 8* of timing out of it to start. Better to have too much pulled than not enough. Get the jetting where you get best MPH. Then start dialing timing back in, 1* at a time, until it slows down, then go back to the previous setting.
 
I realy like Nos whith 300 hp fogger i went from 11,2 to 9,8 in -69 Valiant whith W2 360
 
crackedback said:
You might want to verify the plate jetting. That's a FAT tune up...

Most any n2o plate with a fuel jet bigger than juice is going to be fat.

Maybe call Monte Smith and ask him for a tune up. Most all kits I run the fuel jet is usually .008-.010 smaller than the juice jet.
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thanks for the advice i was going by the nos chart i emailed monte ill see if i get a return email thanks
 
bad440 said:
i would swap that around the nos guy monte smith gave me the rundown and said bigger jet for nitrous side smallerfor fuel too rich is worse than too lean
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thanks after doing more research many say the nos charts are way to rich so if i use .061 n20 and .055 fuel might be just right of course with a good tuning and reading the plugs. i did a calculation i found online and with this jet combo and 6.5 psi fuel pressure and 900 psi bottle pressure it should be 142.83 extra hp to the rear wheels thanks for pointing me in the right direction.:burnout:
 
make sure you back the timing off if you are going to spray it. once you try it you will want more and more of it. have fun
 

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Duster Drag Car said:
looks sweet
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here's the #s that monte quoted..55 nitrous .47 fuel=100 2 degrees reta. rd..63 nitrous .53 fuel =150 4 degrees retard .71nitous .61 fuel =180 6 degrees retard.thats as big a hit that the kit can safley utilize.he also said 150 2 steps colder on the plugs.the 180 another step colder.....that is for the sniper and superpowershot kits.:burnout:that is with 5 pounds fuel pressure.
 
I used a sneaky Pete 100 shot on my completely stock but rebuilt 360 in my van only ever used it for a few second to gain an edge in street races later built the motor more but never had a problem then again it was only short burst not 1/4 mile runs
 
bad440 said:
here's the #s that monte quoted..55 nitrous .47 fuel=100 2 degrees reta. rd..63 nitrous .53 fuel =150 4 degrees retard .71nitous .61 fuel =180 6 degrees retard.thats as big a hit that the kit can safley utilize.he also said 150 2 steps colder on the plugs.the 180 another step colder.....that is for the sniper and superpowershot kits.:burnout:that is with 5 pounds fuel pressure.
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thanks for info he emailed me some info i swaped the jets i had .061 n20 and .055 fuel wont be tuning till spring
 
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