I've been reading a lot about boosted and sprayed engines as of late, but nobody has answered this question.

Take a well-tuned, stock block GSR turbo engine for example. This engine can safely do 275-300hp for quite a while with no problems. That is 150hp over stock, aka the equivalent of a 150shot of nitrous. How come nobody is spraying 150 shots on their GSR's, with a correct tune?

In theory, you should be able to apply more N20 than boost safely, because nitrous cools the intake tract by up to 40 degrees, thereby lessening the chance of detonation, and increasing density of surrounding air molecules.

From Wikipedia.org:


"In racing, nitrous oxide (often just "nitrous" or "NOS" in this context) is sometimes injected into the intake manifold (or prior to the intake manifold; some systems directly inject right before the cylinder) to increase power: even though the gas itself is not flammable, it delivers more oxygen than atmospheric air by breaking down at elevated temperatures, thus allowing the engine to burn more fuel and air. Additionally, since nitrous oxide is stored as a liquid, the evaporation of liquid nitrous oxide in the intake manifold causes a large drop in intake charge temperature. This results in a denser charge, and can reduce detonation, as well as increase power available to the engine."

So ultimately, I've rationalized that with mechanically equivalent engines, Nitrous should overpower boost. There is no drivetrain loss from having to spin a turbo, less exhaust backpressure, no turbo lag, cooler engine temps and less weight for the setup.

Can someone please enlighten me as to why we can't spray 150 shots on our honda engines safely??

 

well im sure there are some people that do it but most people like boost, but the price is what wil get you.

turbo goes, vrooommshoooo wooopooopooopoo
nitrous goes. vrooooooommmmm

you can't hear it. thats another reason why people want a turbo, for the coool *** noises. lol.

nitrous would be A LOT more sleeper'ish, but doesn't it take a bigger tole on you motor than boost does? like the piston rings?

turbo > anything else.

 

one reason people go turbo is because a 150 nitrous shot runs out very fast. plus when you turbo its streetable and you dont have to worry about running out of n20

 

yea thats why i like turbo cause of the noises it makes hahahahahahahahaahhaa!!

 

if you're going to spend the money to build the engine to handle that much nitrous, just get a good turbo setup. Personally i wouldnt want to fill a bottle everytime i wanted to go fast....

 

I'm not trying to debate which is the more economical, or the cooler setup to have. I am just trying to figure out if it is possible to add 150HP w/ nitrous to a stock engine, since it is obviously possible to do so with boost.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Greenery18 &raquo;</TD></TR><TR><TD CLASS="quote">I'm not trying to debate which is the more economical, or the cooler setup to have. I am just trying to figure out if it is possible to add 150HP w/ nitrous to a stock engine, since it is obviously possible to do so with boost. </TD></TR></TABLE>

Of course it is possible. But one thing that sucks, is when you are off the bottle, without a switchable map program, the car runs like *** at full throttle. There are people that do it, I remember a local guy sprayed a **** load of nitrous on a stock gsr way back in the day and ran some real good times. It was upwards of a 200 shot i believe. But the car was pretty much a full race car and never saw the street.

 

i know my friends ls engine was on a 100 shot untuned for 6 months and eventually broke a rod. And my b16 was on a 75 shot dry untuned for a good amount of time before i brokes a piece off one of my intake valves. I would beat boosted b16's from a dig in a 1/4 mile race. It was a lot of fun. The only thing that i didnt like is when it got too hot in miami and my bottle pressure would rise to too high of a temperature.

 

I have no correct answer but I believe it might have something to do with the onset of the extra power. Boost is adding more air, to which you add more fuel, gradually, whereas nitrous is suddenly adding a chemical at over 900psi. This chemical also causes a sudden and extreme temperature drop which pistons don't enjoy.

I've never used nitrous but don't you only get about 3-5 runs from a 10lb bottle with a 150 shot on your averave sub 2.0 4 cyl?

 

my 75 shot lasted almost like 25-30 full 1/4 mile runs. It was a ton of fun.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Greenery18 &raquo;</TD></TR><TR><TD CLASS="quote">
Can someone please enlighten me as to why we can't spray 150 shots on our honda engines safely?? </TD></TR></TABLE>

Can't has nothing to do over it, it's shear preference.

When you tune a nitrous engine, you have to pull timing just like on a boosted engine. The difference is, boost is there every time you step on the throttle, nitrous is not.

When you tune a nitrous engine, technically you're still tuning a N/A engine. This is of course assuming we're not adding it on top of forms of FI. So basically you have to pull a ton of timing in your full throttle (0" vacuum) portion of the map. When you're off nitrous the car has NO power at full throttle. When you're on the bottle obviously things change, but it's not much fun on the street without it.

Turbo/Supercharger is just preferred over nitrous, that's all.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by !moops vs moors! &raquo;</TD></TR><TR><TD CLASS="quote">I have no correct answer but I believe it might have something to do with the onset of the extra power. Boost is adding more air, to which you add more fuel, gradually, whereas nitrous is suddenly adding a chemical at over 900psi. This chemical also causes a sudden and extreme temperature drop which pistons don't enjoy.

I've never used nitrous but don't you only get about 3-5 runs from a 10lb bottle with a 150 shot on your averave sub 2.0 4 cyl?</TD></TR></TABLE>

I think you're right about the power onset thing. Maybe this can be alleviated with a nitrous controller--one that adds like 75hp, then the other 75hp, so there is less instant stress on the engine.

And yea you would probably only get 3-5 runs using a 150shot.

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by SovXietday &raquo;</TD></TR><TR><TD CLASS="quote">
When you tune a nitrous engine, technically you're still tuning a N/A engine. This is of course assuming we're not adding it on top of forms of FI. So basically you have to pull a ton of timing in your naturally aspirated portion of the map. When you're off nitrous the car has NO power at full throttle. When you're on the bottle obviously things change, but it's not much fun on the street.</TD></TR></TABLE>

Systems like hondata or MSD allow you to pull timing only when spraying, and/or build seperate maps. It can even be done with a V-AFC II.

 

there are pros and cons to both
its a matter of budget, simplicty, how a motor is built, what are you building your motor for etc you will typically get more torque throughout the powerband with the nitrous then turbo

 

well i think the issues you start talking about are one, the bottle pressure. that is going to vary from run to run as well as the begining of the run to the end. that means your never going to get the exact same amount of n20 per spay. also with 150 shot i think you are going to start running into some distribution issues with that amount out of a single nozzle, the answer then of course is direct port. but most will go turbo long before they spend a ton on a direct port set-up tuned correctly.

also ive seen plenty of cars not get the "claimed" amount of HP boost from the shot they are using....

 

I had a stock gsr nitrous setup in my hatch before I went turbo. I only had a 75 shot on it but with good tuning it made over 125whp on the dyno (dyno'd 160 on the motor). Went 12.0@115 with this setup. It was alot of fun and very sleeperish but eventually I moved on to something with more potential.

 

well on my 75 shot dry i made 77 whp extra on my b16a2 with full bolt-ons.

 

Nitrous creates alot of cylinder pressure which likes to break stock pistons. Also everything happens very fast with nitrous compared to turbo so one mistake and you are burning a valve or breaking a piston.

 

im pretty sure you already decided what you want...

 

nitrous or turbo it really dosnt matter both have there pros and cons..


turbo, you can run duel maps and have a pump gas tune and a race gas tune to keep it very streetable just like with nitrous you can do the same. The only down side really to nitrous is you gotta keep filling the bottle vs turbo its always there. As for problems with the motor, nitrous seems to be a lil harder on the rings but turbo isnt the easiest thing on the rings either... If you build a motor build it to the specs of the way you plan to go either turbo or nitrous.


We spray a 300 on top of a stock 572ci short block no prob. its a profogger (direct port) but we run a seperate fuel system for it to make sure the system always has enough fuel so theres no chance for leaning out and going boom. with nitrous one mistake and boom. With turbo same thing applys if your tune is fucked up then boom so just make sure you do it the right way with out causing problems down the road.

 

bump status

 

red hatch.. can you (im) me that pic in your sig. the fullsize.. i want to check out the cam gear holes....

 

i dont have it i got it from some website like 2 years ago.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Greenery18 &raquo;</TD></TR><TR><TD CLASS="quote">I'm not trying to debate which is the more economical, or the cooler setup to have. I am just trying to figure out if it is possible to add 150HP w/ nitrous to a stock engine, since it is obviously possible to do so with boost. </TD></TR></TABLE>

Unless you pay a crapload to setup a pimp-*** multi-stage NOS setup, turbo is just easier. Otherwise a single-stage 150 shot will deliver an assload of torque at that RPM, then taper off in an almost linear fasion. There was a b20 posted a while back that had an accidental spray happen at ~2500 rpm on the dyno sheet. Can't remember specifics, but ended up being almost 400lb/tq at that rpm, but no more than 250whp. Imagine if all turbo setups did this - 20psi by 5000 rpm, falling to 5psi by 8500 rpm. You'd just have traction problems at low speeds, and slow cars when they can get traction. Most street NOS setups aren't huge, and they aren't usually activated at low rpm's.

And for the guys with a lead foot like me, NOS will cost a ton after 10k miles.

 

if the turbo raises the power of the car about 150 extra horses and say you can spray a shot and get the same power. turbo is not as hard on your block as nitrous. i used both on both of my gsr and my red gsr is a whole lot faster. facotory pistons cant take the beating of what nitrous pushes out you did say stock gsr right.. it will soon melt the top of the piston with all that heat from nitrous. turbo is better bang for the buck and you don't have to keep refilling it

 

Ok the problem with nitrous is the initial hit. The INSTANT surge in power, insread of gradually going up/building boost. You can use progressive controllers to make it safer. For instance you could set it up to launch with a 75 shot, and have it work up to a 150 shot by the end of the track.