hate to sound like an idiot but iv never used nitrous before. the car is plenty fast with out it but when i do want to try it what are some rules of thumb i should maybe be aware of. between certain rpm's? from take off or from a role? duration of time to spray? my set up is only a 100hp shot and its controlled from a button inside. any tips would be great. i smoked a 351 mustang last night and it was with out nos or being tuned in yet so now my wheels are turning on using the nitrous

thanks

 

I always wondered the same! lol I never used nos before but planning on giving my engine a boost and go with a 75 shot.... I would have to say that the best time to use it would be right when you hit the power range on your cam, say your came is a 2500-5800 cam then I would hit it right at 2500 but thats only my guess.

Hopefully get some feedback from the ones who've had experience with it.

 

ditto. i know i want to take my car to the track this summer and find out what i'm running but i want to also make sure i know how to get the best out of my run. i dought i'll use it on the street... its scary fast already for me.

 

Generally you'd wire in your nitrous with a few switches:

- WOT switch - such that it can only turn on when the gas pedal is all the way downto the floor. This is mounted on your carb.
- Interior switch - You have to have it switched on in the car (duh)
- Window switch - This isn't always there, but is very nice. It'll take a signal from your ignition system, and only allow the nitrous to work between a preset RPM range.

With all of those in place, you just flip the switch on (make sure bottle is open), and once your foot hits the floor, and RPM gets up, you're gone. It's never like it is in the movies with a big red momentary switch

 

ya id have to go buy that stuff and do some rewiring. but i understand what you mean. is there an rpm range that nitrous should be used within? right now i just have the "big red momentary switch" in my ashtray lol

 

No red switch ... well that sucks, I think my nos ideas are shattered lol jk ... well thats funny so you would have to have the switch turned on and the bottle already open before you start the run. Then the wot sensor switch would kick in the nos once your hitting the certain rpm, or at wot, on whatever its set to do.

So then I think the question is, when would be the correct time to have the nos kick in such as what RPM/gear/speed like the OP is asking.

 

Most of the time when racing its off the line or just off the line. Or if you feel like you are going to lose the race make sure the bottle is on then hit the button.

 

thanks for the tips guys.

 

alot depends on your car and how well it plants the tires..from a dead stop when you foot hits the floor mash the button..if it blows the tires off try it again but wait till the car is moving some before you mash the button...i use a throttle switch on the carb.

remember the quicker you can get on the button the quicker the car will be...i have ran nitrous for 20 years on my cars...longest i have ever been on the bottle is 12.2seconds at the dragstrip in a 5.0 mustang...shortest full pass was was 7.8sec in my 68 camaro..

 

When not to use NOS for passing

the NOS refilling station
a Strip Clubs
Hookers
School Girls
Sheep
the drag strip


When to use NOS for passing

School Zones
Cross Walks
Hospital zone
Stopped school bus
Slow ambulance only going 80


If you find the police behind you with their lights going, they are only there to safely escort you alone you way, don’t slow down. They will soon get ahead of you, park and wave as you drive by.

 

My setup is really simple... Arming switch and the little red button on my shifter. When to use it? Generally, you want to activate the system above 3,000 rpm. Since my converter flashes at 4,200 rpm, I just stomp on the throttle and hit the button. Couple of friends have had theirs wired up like that since the 90's. Another nice add-on is the purge solenoid, that also gets armed with the rest of the system. Don't go crazy with bottle pressure and NEVER warm up the bottle with a torch. Yeah people have gotten away with it for years but it's not safe.

 

thanks guys really good stuff well other then gumpy who i think is just looking to see another fun police chase on you tube that involve me and a group of cop cars so he can show his friends and say "yup i did that" as i get tasered and scream like a little girl lol lol

 

note most places have voted in "fast n furious" laws.

get caught with NOS hooked up on the street, automatic street racing offence that may mean you forfit your car for good to the crushers.

 

i'm in michigan so i think i'm good. unless i'm around detroit cops then its cover your tail and run

 

id check into it, they snuck that law into effect under cover like most things here in Ohio.

yet turbo n super chargers are fine.

 

ya i'll look into it cuz my bottle is right out in the open so they would see it. gotta love intrusive government. police state USA is on its way.

 

Be careful that you dont use to much tho you might blow your floor out its very real

 

So to answer the original question:
- only at WOT (wire a WOT switch), part throttle or no throttle something will go boom
- only above about 3000rpm (you get whatever it's set to at whatever rpm that you turn it on at, the lower the rpm you hit it with a set hp shot, the more torque it makes and the more likely it is to break things, below around 3000rpm the torque increase will generally break things
- you don't want the spray going when you it the rev limiter pulling either ignition or timing while spraying means something will go boom

Some people run a window switch setting a bottom and top limit but it's not 100% necessary, typically by the time you hit WOT you're at a decent rpm (especially with an auto), and you should have your rev limit set a bit above your shift point so you shouldn't run into it. The window switch just gives you some extra safety if something goes wrong.

I generally use a progressive controller and sort of push the limit. I like the jacobs nitrous master mind (there are newer, more modern setups out there, but I've had one for years). It allows you to set the progressive hit depending on RPM, so you get more hp at a higher rpm, a little more like a natural power curve. I usually put much larger jets in then what I intend to really use, then set the "on" setting for about 2500-3000rpm and the "full" value for way past what I'm going to run. That way it ramps in slowly and I can control what percent of the total hit I get by setting the max rpm. The closer you get to the RPM range that it actually runs in the closer you get to getting the full hit. I also set the rev limiter to something reasonable and the controller kills the spray before it hits the limit.

I usually get away with running a much bigger hit than most think is possible, and it comes in gently enough that most can't tell I'm spraying

 

great info guys you rock, thanks

 

Why do I always hear that people take spark away when spraying?

I'm assuming that they retard the spark right before the spray to keep things safe from knock counts? Not sure but the reason I ask is because i notice that my EBL has an option to take spark away for N02 ?!


Good info! Reading all of this gives me butterflies lol... I want to add a shot on my new build but all of the nos horror stories make me not want to try it. :/

 

What is an EBL?

 

Sorry, its a really cool programmable computer lol
Bobr makes it... and it has settings made for N02 setups and all. You can run TBI, TPI, and I believe there may be other types of injection systems you can run it with.

This is EBL:

http://www.dynamicefi.com/

 

that is cool! i like that....

 

They retard the timing, less timing = less chance of detonation when running the bottle.

Just a quick note about hitting the limiter using nitrous, friend of mine did that. He was out testing on some back roads with a new setup and black tracking the whole quarter mile but said it just wouldn't RPM. Well, come to find out it was hitting the rev limiter that was set at 7800 rpm. Ended up melting some pistons, oops. I'm sure someone is thinking, why didn't he just look at the tach? You tend to keep your eyes on the road when the car is trying it's best to head into the ditch lol.

 

Spray shouldn't make an engine more detonation sensitive, if anything, assuming no hot spots the faster burn rate should decrease the likelyhood of detonation happening (I can explain, but it will get long, without some combustion theory I realize that that sounds counter intuitive) but:
1- detonation with the increased cylinder pressure while spraying will break things faster- you can get away with some detonation NA and not break things right away where you'll break things right away while spraying
2- the engine's power production is less sensitive to actual timing while spraying, you just don't loose as much power running a degree or 2 less timing while spraying as you do NA

Put those 2 together and it's safer to retard the timing a little, and it's easy to give it a little more spray to cover up the power loss= manufacturer's recommend it to cover their asses- they don't want to get the rep that "their **** blows your car up" when the real problem is that the car it was put on had a crappy tune with too much timing to start with.

Same thing with fuel jets/enrichment for most kits... it's not uncommon for the out of the box settings on them to recommend fuel jets that will give you _insane_ low A/F ratios (like in the 10's, I've even seen 9's) and I know of a couple of kits that you can gain on the order of 35-50hp by just running the fuel jet for the next smaller shot. In that case they're covering up all up for the people out there that will slap their kit on a car with a crappy/marginal fuel system, again, not wanting to get the rep that their **** blows cars up even though it's the idiot that slapped it on the car's fault.

FWIW, a few of the manufacturer's used to recommend _no_ timing retard with their stuff, like NX, and I've run their setup with none with as much as a 225hp hit on a stock engine. OTOH, getting back to the JNMM, since you can set it retard with a dial, and it's that easy I usually dial in 1/2* per 50hp, or more if I'm testing a new setup. Same deal with fuel, the JNMM allows you to adjust the progressive curve fed to the fuel solenoid separate from the N2O 'noid so you can easily adjust that during your late night testing runs from your dash without crawling under the hood in the dark with a wrench to change jets.

 

N2o increases the burn rate like a ****. you want to pull more timing with it so you will get all the fuel burned around the right time. also you have a huge increase in cylinder pressure. run too much timing and you will have detonation, which will wreck things quickly when you are playing with nitrous. with the bottle turned on, you will ALWAYS need to pull timing from whatever the engine wants n/a. there is alot of learning going on with nitrous, even today. the new thought process is that a rich jetting is more dangerous than a lean jetting.
just some things i thought i would add to the convo....

 

What ever you do...once you spray you cant ever stop....1 bottle will turn to 2, 2 to 3 and on your third bottle youll have more controll over your finger, or if you run out of heaven juice youll have more self controll.

also go find a nice big long back road for "testing", I have 1 and when ever I get close to it all the memories of my last spray start rushing in and I get the D-Ts, shakes breath tightens, hands get alil wet. ; ) and 1 time my hand just went behind the seat and back to the dash and I HAULEN *** and almost svered off the road (torque kick - broke posi - full bottle pressure)

also you WILL NEED the following:
in addition to your nitrous kit...

Auto meter elect fuel pressure gauge

autometer AFR gauge

autometer nitrous pressure gauge

FULL tank of -93- gas after running 1-2 FULL tanks of 93 to get the cheap gas out.

Ask the good LORD for a safe pass and not to end up with a blown motor

Cooling upgrades:
180 stat
hot fans
adjustable airdamn


THESE ARE REQUIRED!!!!

 

lol sound like you really enjoyed your self patin. thanks for all the tips guys

 

yea, dont forget....spray uses a HELL of a lot of gas....

 

well my wife uses a lot of credits cards so its time i use a lot of something as well lol

 

NOS recommends 2 degrees per 50 HP plus another 2 deg as a safety margin.

I run EBL-ECU so i have available RPM and MPH and N20 retard when N20 is "on". N20 logic is off in bin unless I power up N20 with activation switch at dash.

I am currently with 100 HP jetting and use 4 deg retad in my .bin when "on".

On at 3200 rpms off at 6000(max HP w/o N20 is 5800rpms).

On at 30 MPH to soften the hit to my drivetrain in part due to 12 inch soft thread.

I use an Innovate WB to monitor as well.

 

i thought it was 2 begrees for every 100hp not 50hp.. now i'm confused.

 

its all just a somewhat safe starting point on your tuning. the car may not want but 4 degrees pulled when the guidelines call for 8. the fuel/nitrous jetting is also probably way off with the factory suggestions. but, they dont know what kind of engine,heads,cam,intake,cubes,headers,compression,fuel type,or anything else so they are pretty much shooting in the dark on the suggestions.

 

well thats my next issue.. something i have to get done before i start spraying which is tuning. my motor is still untuned. it only has about 20 minutes on it and i cant get anyone around me to come and tune it. iv worked in machine shops for abut 14 yrs so building the motor wasn't complicated but tuning it... i don't know where to start. if anyone is in the area and feels like some free pizza and pop and fun day of ragging on my car feel free to chime in lolol

 

#1 reason Im saving and spending 2k on one of them Holley FI systems.
[its more for the full package like I need]

It can handle anything you throw at it and it will auto learn and self tune, turbo, NOS, anything, its ready for it right out of the box.

Holly tech suggest I use both NOS and a turbo, little giggle gas for cooling.

 

ya i cant sink any more $ into this car right now. i just put 9k into it and its fast enough. i can be patient on the extras lol i doubt i will use the nos that often on the street(i could be wrong) other then if i take it to the track. my last camaro was doing low 12's and this one feels like it would blow that one away easily so no hurry.

 

NOS systems wants you to start safe. So they suggest 2 ded/50HP plus a additional 2deg. Note NOS recommends 6 and I am at 4. As stated by poster above they want you to have a successful start on tuning. Rather than detonate on first use.

 

"safe start on tuning"..... *sight* wheres the fun in that lolol a big boom is a great life lesson lolol

 

Faster burn rate actually decreases the chances of detonation, again, there are companies that don't recommend pulling any timing, and they don't regularly blow stuff up.

As far as rich being more dangerous... not sure that I agree with more, but it's just as dangerous. Both can cause detonation. The thing is that people tend to get themselves in trouble more often by going lean than rich.

heh, my first night doing just that I had a great big racoon run out onto that long back road which made a tremendous mess when I smacked it, and made those shakes much worse...

not sure I agree with most of those being needed, a cheap bottle gauge is fine, or I've used an NX bottle heater setup that powers the heater to get the pressure up over a set level.

 

Great big fireballs are kind of crappy ways to learn something, but they are freaking cool. Shoot some video

 

video will be shot lol and i'll take pictures of the of the crash scene and engine parts if i did something wrong so we can all have a good laugh lololol

 

Hmm, its starting to not sound so bad anymore. I had a friend telling me about having to change the oil 3 times as much and getting those heavy duty gaskets and all this other stuff because N02 was so hard on the engine...

Also, you have to heat the bottles to raise the pressure? Didn't know that.

And what the heck is JNMM?! lol

 

I wouldn't listen to your friend on performance stuff. During the summer, the bottle should be plenty warm. Winter time you can use an electric bottle warmer that's either controlled by pressure or temperature. The fancy pants way is a temperature controlled hot water bath. Again, NEVER use a torch to warm up the bottle.

 

If a faster burn rate decreased chances of detonation, you would want to run 87 octane in a high compression engine. (instead of 93)
if your engine is where it wants to be with its n/a timing, you SHOULD be pulling timing on the bottle. otherwise, you are overtimed. and that is what causes the REAL damage, not so much the a/f ratio.

 

detonation and too much timing are 2 different problems which both result is the piston rocking in the bore and could make a rattling noise. Detonation does it much faster and does much more damage. A faster burn rate makes detonation less likely, it decreases the time there is for detonation to happen.

 

Some cars may want less timing pulled, some want more. My 383 with a 150 shot ran 32 deg timing, thats only 2 deg less than optimal for n/a. I track tested and dyno tuned the car from 32 deg to 39 deg timing and n/a it ran best at 34 deg. Nitrous I began pulling 6 deg per the rule of thumb, 2 deg per 50hp and dialed in air fuel ratio from there. At first it was pig rich and then leaned out to about 12.0 to 1, i added timing back. added in 4 deg to get the best mph. From simple lean out and timing, i gained 4mph on a mid high 10 second car!.

My friends stroked 350 to 408" motor using same AFR 195 heads, but on a carbed application dyno proven made more HP with more timing pulled. I think hes pulling 5 from his optimal n/a tune, which I believe was 36 deg. His 150 hit made 530whp. So those heads are liking 31-32 deg of timing on 2 different applications, but my EFI motor had different n/a timing than his carb. So him pulling 5 deg vs me pulling 2 had totally different results, even tho we are running about same timing

My turbo car sees this...I get knock retard if I'm too rich and once leaned out, it goes away. To rich can wash out the cylinder walls and thus you have no oil lubricating the bore and cooling the piston. You can overheat the piston and expand the rings til you break the lands. Too much gas in the oil can also wipe out your bearings.

 

well i sprayed it and it wasn't even fun just made me spin more. i gotta find a way to hook up better I'm laying 130+ft burn out with out using the nitrous all my ummph is gone by the time i start to hook up. as far as the timing being talked about above mine is timed to 38 and it responded beautifully last night when i sprayed the nos. no misses, no knocks, i think i even heard the motor whisper"mmm more juice" lol

 

have you considered a controller to begin spray at a higher MPH?

 

ya i have and i just cant sink any more money into it right now. we're remodeling our home right now plus i have a renter in one of my other homes who's not paying and $ is just kinda tight right now. i was trying to find a poor mans solution lolol i know they dont work, you get what you pay for right

question, wouldnt spraying it at higher rpms just help it spin all the more? last night i sprayed it at around 4k.

 

Keep an eye out for a used EBL