One other thing to point out. Most people are not going to use a purge solenoid. That means that you will be seeing gaseous nitrous from the nozzle at first activation. Gaseous nitrous is far less dense with far less mass than liquid nitrous, so the hit is very soft compared to injecting liquid nitrous from the get go. That would give a bit of a buffer to let the O2 sensor catch up to a slower rising lean trend.
Turbo Spooling Nitrous Oxide System Basics
- Thread starter Alky V6
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When I mentioned that I avoid lean firing while on the nitrous, I'm talking about ratios that record in the mid 13s to mid 14s to one. A very quick spike to that level has not presented a problem, but anything longer than a quick spike means an intake backfire in my case.
Exactly. Utilizing 2 solenoids inline on a dry setup is my preference as well. Think of the worst that can happen and you'll figure out why.
Very good point. That gets back to the wet system and using the hose lengths from both the fuel and nitrous solenoids to time when the two different compounds under two much different pressures arrive at the nozzle to minimize any deviation from the intended n/f ratio.
First a bit about solenoids. Like the bottle valve, make sure the type of solenoids you use are rated for the size of hit you're shooting for. NOS recently announced that they've come out with better materials so that their solenoids can now be pulse width modulated with much better durability than before. Kits are available to upgrade older model solenoids.
Yes. That is a wise choice. The second solenoid is a backup incase one of the solenoids sticks open. That is very much recommended on systems where the solenoids will be pulse width modulated.
Not having a purge solenoid is the best way I know to have an inconsistent launch or tune.
(I'm just sayin.......)
B
All of the major nitrous suppliers have solenoids capable of PWM operation. A secondary solenoid is a good redundancy. Don't forget a Nitrous filter as well, trash in the solenoid can prevent it from shutting completely.
Yes, they can be pulse width modulated, but it is recommended that they be rebuilt more frequently than a solenoid that is not. At least that is what I understand with the NOS brand solenoids. With the recent upgrade, the frequency between rebuilds can be extended.
Yes, filters should be used for all solenoids involved in a nitrous system.
If the nitrous is used just to spool up the turbo and is shut down before the actual launch, the problem of inconsistency can be lessened.
I agree with you on the point about the tune. When the gaseous nitrous is purged and the liquid nitrous hits the nozzle, the mixture is going to be upset. Not the way I would choose to use nitrous.
GNVYUS 1
Well-Known Member
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- Dec 15, 2002
- Messages
- 4,344
If I had the cahones to do this, Chevota's way would spool the fastest. Hell, you could do Pre and Post if you really wanted some action. 
Here is a good read about Wet Compression
http://www.caldwellenergy.com/pdfs/WETCOM.PDF
Test graph on page 10
They were using water and gained 9% in output flow, 5psia gain, 50 degree discharge temp drop (even though it was pushing 5psia more) so what what Nitrous have done.
Don you'd be a great member to datalog Nitrous Preturbo, watcha say?
Here is a good read about Wet Compression
http://www.caldwellenergy.com/pdfs/WETCOM.PDF
Test graph on page 10
They were using water and gained 9% in output flow, 5psia gain, 50 degree discharge temp drop (even though it was pushing 5psia more) so what what Nitrous have done.
Don you'd be a great member to datalog Nitrous Preturbo, watcha say?
Yes, there are aditive fuel tables that get used when the computer activates the NOS. These tables allow you to add diferent ammounts of fuel throughtout the rpm band to eliminate rich or lean spots at certain rpm's. The WBO2 is just for monitoring and not the key element in adding fuel. Allowing the computer to turn the NOS on and off eliminates the use of additional TPS switches, rpm windows, and Hobbs switches. It just takes one relay and a couple wires.
Let's get through the basics before we start delving into the fancy stuff.
I know many are anxious to throw their input in, and I do greatly appreciate it, but their are many that are hoping for a system that will not require ECM upgrading. Let's take care of those people first and then we can expand into the wonderful world of fancier control systems. I would like to keep control systems for last, since that could easily turn into a big mess with all the ways that control can be accomplished.
I know many are anxious to throw their input in, and I do greatly appreciate it, but their are many that are hoping for a system that will not require ECM upgrading. Let's take care of those people first and then we can expand into the wonderful world of fancier control systems. I would like to keep control systems for last, since that could easily turn into a big mess with all the ways that control can be accomplished.
Solenoids
Back to solenoids.
Just to recap;
Make sure that the solenoid(s) that are chosen are rated for the amount of hp or flow that you're looking for.
Filters should be used with all nitrous system solenoids. I prefer to mount the filters as close to the solenoids as possible. Specialty filters are available for nitrous system solenoids.
Pay attention to the amperage draw of the different soleniods available, and make sure that they will fit into your electrical system scheme. Wiring, fuses, switches, microswitches, relays, etc., that will be part of the electrical control circuitry will need to handle the amperage draw the solenoids will put on the system. Some solenoids draw much more amperage than others. Pay attention to that.
With a 50-100 shot system, -4 hose for both sides of the system, fuel and nitrous, will be sufficient. AN style fittings are typically used with nitrous systems. The nitrous side of the system will use specially crimped AN hose ends with teflon lined, steel braided hose. Don't cheap out on this hose, and protect it from abrasion and heat!
Back to solenoids.
Just to recap;
Make sure that the solenoid(s) that are chosen are rated for the amount of hp or flow that you're looking for.
Filters should be used with all nitrous system solenoids. I prefer to mount the filters as close to the solenoids as possible. Specialty filters are available for nitrous system solenoids.
Pay attention to the amperage draw of the different soleniods available, and make sure that they will fit into your electrical system scheme. Wiring, fuses, switches, microswitches, relays, etc., that will be part of the electrical control circuitry will need to handle the amperage draw the solenoids will put on the system. Some solenoids draw much more amperage than others. Pay attention to that.
With a 50-100 shot system, -4 hose for both sides of the system, fuel and nitrous, will be sufficient. AN style fittings are typically used with nitrous systems. The nitrous side of the system will use specially crimped AN hose ends with teflon lined, steel braided hose. Don't cheap out on this hose, and protect it from abrasion and heat!
This is a very important topic. If you really want to dial in your nitrous system, pay attention to this.
This may not be as important with a small shot size, since the motor will tolerate a small lean or rich spike during the moment that the nitrous system activates, but as you go larger with the system, this topic does gain importance.
This pertains to wet systems.
The best positioning of the solenoids for a single nozzle setup would be to have the solenoids mounted right off the nozzle. This way, when they both activate, the fuel and the nitrous have a very short distance to travel before exiting the nozzle. The nitrous, being under much higher pressure, will begin spraying from the nozzle slightly sooner than the fuel, but the difference will be minimal. The further the solenoids are mounted from the nozzle, assuming that both are mounted the same distance from the nozzle, the more the time differential becomes in regards to the nitrous reaching the nozzle before the fuel. That creates a longer lean spike for the engine.
Hose diameters and lengths create resistance to flow. That's the way of the world and you can't get around that. If both solenoids are opened at the same time and the nitrous and fuel have to travel through 3 feet of -4 hose, the nitrous being under 950 -1050 psi pressure is going to get to the end of the 3 feet before the fuel, being under 8 or 45 psi pressure.
If you just can't mount the solenoids that close to the nozzle, you can use varying lengths of hose for each solenoid to change the timing as to when the two elements reach the nozzle. Of course, the nitrous solenoid would need a longer hose than the fuel side. We want to give the fuel side a head start since it is under much lower pressure and will be slower at getting to the nozzle. Another way to accomplish a better timing to the nozzle would be to control the opening of each solenoid separately or use a delay box to open the nitrous side slightly after the fuel side was opened. The idea with both methods being to make sure that the fuel and nitrous reach the nozzle at the same time so that we control the n/f ratio at initial activation as best we can.
A good example is my system. I have a spider distribution manifold that feeds to six fogger type port injection nozzles. Each nozzle delivers over 50hp worth of nitrous and methanol fuel flow. The fuel solenoid is mounted practically directly on the distribution manifold. The nitrous solenoid has a 3 foot hose between it and the distribution manifold. Even so, I get a very slight lean spike on initial activation of the system. Not enough to worry about making the nitrous hose any longer, but it just proves the point of how much faster the nitrous can get to the nozzle versus the fuel side. I've found that as I stepped up with the system hp level (larger jet sizes) I've had to go from a 1 foot, to a 2 foot, and now a 3 foot hose between the nitrous solenoid and the common distribution manifold.
This may not be as important with a small shot size, since the motor will tolerate a small lean or rich spike during the moment that the nitrous system activates, but as you go larger with the system, this topic does gain importance.
This pertains to wet systems.
The best positioning of the solenoids for a single nozzle setup would be to have the solenoids mounted right off the nozzle. This way, when they both activate, the fuel and the nitrous have a very short distance to travel before exiting the nozzle. The nitrous, being under much higher pressure, will begin spraying from the nozzle slightly sooner than the fuel, but the difference will be minimal. The further the solenoids are mounted from the nozzle, assuming that both are mounted the same distance from the nozzle, the more the time differential becomes in regards to the nitrous reaching the nozzle before the fuel. That creates a longer lean spike for the engine.
Hose diameters and lengths create resistance to flow. That's the way of the world and you can't get around that. If both solenoids are opened at the same time and the nitrous and fuel have to travel through 3 feet of -4 hose, the nitrous being under 950 -1050 psi pressure is going to get to the end of the 3 feet before the fuel, being under 8 or 45 psi pressure.
If you just can't mount the solenoids that close to the nozzle, you can use varying lengths of hose for each solenoid to change the timing as to when the two elements reach the nozzle. Of course, the nitrous solenoid would need a longer hose than the fuel side. We want to give the fuel side a head start since it is under much lower pressure and will be slower at getting to the nozzle. Another way to accomplish a better timing to the nozzle would be to control the opening of each solenoid separately or use a delay box to open the nitrous side slightly after the fuel side was opened. The idea with both methods being to make sure that the fuel and nitrous reach the nozzle at the same time so that we control the n/f ratio at initial activation as best we can.
A good example is my system. I have a spider distribution manifold that feeds to six fogger type port injection nozzles. Each nozzle delivers over 50hp worth of nitrous and methanol fuel flow. The fuel solenoid is mounted practically directly on the distribution manifold. The nitrous solenoid has a 3 foot hose between it and the distribution manifold. Even so, I get a very slight lean spike on initial activation of the system. Not enough to worry about making the nitrous hose any longer, but it just proves the point of how much faster the nitrous can get to the nozzle versus the fuel side. I've found that as I stepped up with the system hp level (larger jet sizes) I've had to go from a 1 foot, to a 2 foot, and now a 3 foot hose between the nitrous solenoid and the common distribution manifold.
Next subject to consider is the blow down of the volume of nitrous that becomes trapped after the nitrous solenoid shuts down.
With a long hose between the nitrous solenoid and the nozzle restrictor jet, after the nitrous solenoid has shut down, a volume of nitrous, still under pressure in the hose, will take time to blow down through the nozzle jet until pressures have equalized on both sides of the nozzle restrictor jet. If this volume happens to be liquid nitrous, that blow down will take a little longer since the liquid in the hose will begin to convert and expand into a gas state and in doing so will help re-pressurize the hose until all the nitrous is expelled throught the jet. The total mass of nitrous in a liquid state is far, far more than it is when in a gaseous state. Basically, this means that the nitrous will continue to flow from the nozzle for a short period of time after the solenoid has shut down.
On the fuel side, when the fuel solenoid shuts off, the fuel will stop flowing under pressure. If the hose between the soleniod and the nozzle is long, fuel will be trapped in that hose and will trickle or be slowly sucked from the hose each time manifold pressure falls.
So,... with long hose lengths between the solenoids and the nozzle, when both solenoids shut down, fuel side will stop flowing for all practical purposes, but the nitrous side will take some time to blow down. In my unique case that blow down time is .18 of a second.
With a long hose between the nitrous solenoid and the nozzle restrictor jet, after the nitrous solenoid has shut down, a volume of nitrous, still under pressure in the hose, will take time to blow down through the nozzle jet until pressures have equalized on both sides of the nozzle restrictor jet. If this volume happens to be liquid nitrous, that blow down will take a little longer since the liquid in the hose will begin to convert and expand into a gas state and in doing so will help re-pressurize the hose until all the nitrous is expelled throught the jet. The total mass of nitrous in a liquid state is far, far more than it is when in a gaseous state. Basically, this means that the nitrous will continue to flow from the nozzle for a short period of time after the solenoid has shut down.
On the fuel side, when the fuel solenoid shuts off, the fuel will stop flowing under pressure. If the hose between the soleniod and the nozzle is long, fuel will be trapped in that hose and will trickle or be slowly sucked from the hose each time manifold pressure falls.
So,... with long hose lengths between the solenoids and the nozzle, when both solenoids shut down, fuel side will stop flowing for all practical purposes, but the nitrous side will take some time to blow down. In my unique case that blow down time is .18 of a second.
kingots2004
Member
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- Nov 6, 2007
- Messages
- 995
i always blip the nitrous durning a burn out. (this was on my other car and truck. i havent sprayed my buick yet)
kingots2004
Member
- Joined
- Nov 6, 2007
- Messages
- 995
i got a nos sniper kit for 4to6 cylinder cars. it has a 35 50 75 jet selection. it was 300 off ebay and had everything including throttle switch and relay. they also have a v8 kit that is 100 125 150 if i remember correctly. i believe it uses the same selonoids as my kit so that would be a good kit to start with.its a wet kit also.
