Too Much Nitrous

[ar0ck]

I was looking into a nitrous kits, but it seems most kits are adjustable from 75-100-200 shots. What do you guys think Is too much? And what is safe for general street useage, and once in a while some track trips? Anthing else in my car I might need to upgrade too?

I was mainly looking at the Nitrous Express Single Shot plate systems.

The plan is to run a normal 10lb bottle where the back seats were, and have a small control panel up front. With the usual accessories like a bottle warmer & purge system.

[NJSPEEDER]

it is tough to say what is "safe" for a particular motor. camaroracer1992 had a stock 305 with a 125shot that never missed a beat, even after he put prolly 30bottles through the thing. when we took teh motor apart it was so clean you woudl swear there was only like 10k on it.
i say get a kit with 75/100/125 pills and set it to where ever you feel comfortable drivin it.

later
tim

[90FormulaWS6]

125 is definitely pushing it 75-100 is definitely feasable on stock internals... as long as its a dry shot

[jims69camaro]

how is the system going to reference how much fuel is needed? if you don't increase the fuel when you shoot the nitrous through it, you A) will never be happy with your purchase, B) will most likely not feel any difference between stock and with the nitrous system, C) may actually cause harm to your motor. remember, fuel makes power - nitrous just lets you burn more fuel.

a "dry shot" doesn't add any fuel to the system. that would be ok if you upgraded your fuel delivery through your injectors. otherwise, there is only one way to go and that's with a wet shot. a wet shot brings fuel with it, so you get the extra fuel you need for the amount of nitrous you are adding to the equation. there are two hoses running to the plate, one from the nitrous bottle and one from your fuel system.

These are three basic types of nitrous systems: dry, wet, and direct port. The most misunderstood is the "dry" type of system. A "dry" nitrous system simply means that the fuel required to make additional power with nitrous will be introduced through the fuel injectors (remember, fuel makes power, nitrous simply lets you burn more of it). This keeps the upper intake dry of fuel. We accomplish this by two methods. First, is to increase the pressure to the injectors by applying nitrous pressure from the solenoid assembly when the system is activated. This causes an increase in fuel flow just like turning up the pressure on your garden hose from 1/2 to full. The second way we can add the required fuel is to increase the time the fuel injector stays on. This is accomplished by changing what the computer sees, basically tricking the computer into adding the required fuel. In either case, once the fuel has been added, the nitrous can be introduced to burn the supplemental fuel and generate additional power.
The second type of nitrous kit is the "wet" style of kit. These kits include carburetor plate systems and add nitrous and fuel at the same time and place (normally 3-4" ahead of the throttle body for fuel injected applications or just under the carb as with plate systems). This type of system will make the upper intake wet with fuel. These systems are best used with intakes designed for wet flow and turbo/supercharged applications.

http://www.holley.com/HiOctn/TechSer.../NOSTech1.html

[NJSPEEDER]

the plate systems add both fuel and nitrous together. so it is a much safer systems than the single nozzle set ups that seem to be popular with the late model crowd.
teh level of fuel and nitrous is controlled by pills, similar to a holley carb(concept, not interchangable) and there is a handy little chart that comes with most of teh kits that tells you which fuel pill matches which nitrous pill for each desired power level.

later
tim

[Fasterthanyou]

Do your "usual accessories" include a new fuel pump? If not even a 20shot would be too much. These stock pumps are WEAK! A nice walbro 190 for like $80 should come before anything else.
I've already done a lot of research regarding N2o... I do this a lot actually... research that is, so much so that I end up finding something better to spend my time and money on... researching.... but ANYWAYS ;
There are different systems out there but most have adjustable jets, this is good. You want to adjust your jets depending on your fuel AND nitrous pressure. Pressure drop in nitrous will result in an overly rich and vice versa. Get a carb intake, a carb kit, and an adaptor plate (or must make one). Then you're set, so long as your kit comes with small enough jets for the higher, than carb, tbi fuel pressure.
An alternative is running an extra fuel pressure regulator, but that can get messy.
I think a stock TBI could easily use a 150shot at 2400+rpm and 100shot just off idle. Remember that because of the low engine speeds and tight stock cam that if you spray too early you'll have INSANE cylinder pressures. Talk to Joe (camaroracer1992) about his setup, it obviously worked but I believe he had just about every nitrous goodie on the market.

[camaroracer1992]

up to a 150 shot is good on a stock motor as long as its in great tune. first thing though id recommend a walbro fuel pump, a hevay duty coil, plugs that are 2 steps colder and also gap em at .030. a MSD box woudl nt hurt either my 305 ripped ass set up like that!!!

[jims69camaro]

it's nice to see an N2O thread that has good advice in it. keep up the good work, guys, and we'll get everyone spraying better ETs.

p.s. most guys think that they can get into an NOS system cheaply, which is true, comparatively. it'll still run you about $500 for a good system that you'll be able to depend on time and time again.

[NJSPEEDER]

Originally Posted by jims69camaro

it's nice to see an N2O thread that has good advice in it. keep up the good work, guys, and we'll get everyone spraying better ETs.

this looks liek a good tiem to insert my "you need a turbo" commentary then. hehe



later
tim

[ArCoLoG2]

I've heard this general rule of thumb relating to engine mods...Engines are built capable of handling 50% more horsepower than the stock rating...300 stock horsepower = safe to run a TOTAL of about 450 hp on stock internals...Don't know the accuracy in that one, but I read it multiple times a while back..Just a thought.

And as far as wet shots, you still need to supply the "extra" fuel somehow, the pump is going to have to flow just as much fuel as the dry shot.


(Not responsible for the information stated)
just in case!!

Dave

[Fasterthanyou]

Dave, the 50% rule is pretty useless if you think about it. In an engine there are components that are rated differently and your engine is only as strong as it's weakest part.
A good example is the stock rods. In a cheap OEM small block the nodular cast crank is capable of handling ~800hp. Cast pistons 600hp and PM rods 500hp. As you can see, rods are usually built the smallest, this actually decreases the wear and tear on the bearings because they are light weight. A heavier rotating assembly at high RPM will require more oil than a lighter assembly.
Now there is the other problem with engines... they're ability to put up with damaging forces like cheag gas, stupid operator (not me), too much timing, exhaust leaks, intake leaks, nitrous . If you detonate with cast pistons you can kiss the piston tops good-bye, fordged will survive longer without failure.
A classic example of the above is the GN motors. It's a 60's engine with cast internals (including pistons but higher SI content) and they've seen 600hp on stock bottom ends. If you do the math it's pretty amazing.
This is why I don't believe in building a forged engine unless you've blown up your previous engines with poor tuning or are shooting for >600hp. Now that's just talking about a 350, a 383 and 400 have a longer stroke which puts more stress on the rotating assembly (higher velocities and accelerations). So for a long stroke motor you NEED to use high quality rods!!! I can't stress this enough. I've seen my share of wimpy rods in 383's spinning over 7000rpm and lossing a rod, it's almost as prevalant as the ford guys cracking their stock blocks.
So spray away with the nitrous but be sure you don't have too much timing or you'll blow it up.

[ar0ck]

All I ever wanted was a little gigle gas in my slightly modified 350

But thanks for the reading 8)

[jims69camaro]

Originally Posted by TransAm4Life

All I ever wanted was a little gigle gas in my slightly modified 350

But thanks for the reading 8)

that's the thing, there really are quite a few things involved in making the decision to run nitrous if you want to stay out of trouble.

[ar0ck]

I just want to drop one hole second of my 1/4 time. My friend with his 93 5.0 shaved off a full second with a 80-shot.

[jims69camaro]

cheap insurance on any car with nitrous oxide: and Air/Fuel guage that'll reach inside the passenger compartment or can at least be viewed from the driver's seat. or, if you are in a computer controlled vehicle, get yourself a laptop and some software so that not only can you map it out but you can affect changes in real time. we don't want your next post after the "I installed N2O" to be "I melted three pistons".

[ar0ck]

Originally Posted by jims69camaro

cheap insurance on any car with nitrous oxide: and Air/Fuel guage that'll reach inside the passenger compartment or can at least be viewed from the driver's seat. or, if you are in a computer controlled vehicle, get yourself a laptop and some software so that not only can you map it out but you can affect changes in real time. we don't want your next post after the "I installed N2O" to be "I melted three pistons".

No computer, im just looking for a straight WOT activated system (open the bottle and flip the switch).

[jims69camaro]

Originally Posted by TransAm4Life

No computer, im just looking for a straight WOT activated system (open the bottle and flip the switch).

that was meant to know what the A/F ratio is when the nitrous is engaged. now that the air is cooler, you might be able to get away with throwing it on and running without worries. i wouldn't do it without knowing what the air/fuel ratio is, though...

[Formula4Success]

A good rule of thumb is: 20-25hp shot/cylinder. So if you do the math, on the safe end, you're looking at a 150 shot....you might even be able to get away with a 175, however, at that point you're pushing it. Also, NEVER GET A DRY KIT. It leaves too much room for detonation and then KABOOM go the internals. With a wet kit, you're introducing the fuel/nitrous mix at the same time, so you're less likely to get a detonation from the nitrous getting sucked into the cylinder once the fuel has already ignited. I don't feel like writing a lot...if you want a more detailed explanation, PM me or what not. So, definately go with the WET KIT. The LS1s are a pretty stout block, so they can handle it, even with the slight overbore on select cylinders *BTW: I Hate 10-bolts* ->Been through 6 thank got all on warranty.