What are the differences between a dry nozzle and a wet system?

[mrr23]

answers from the manufacturers:

The "dry" system uses the factory fuel injection to enrich the nitrous introduced into the engine. The flaw with this technology is that no matter how much nitrous arrives at a certain intake port it always gets the same preset amount of fuel, or if a fuel injector becomes clogged engine damage will result. The "Wet" technology introduces a precise amount of fuel and nitrous through a high tech mixing nozzle that atomizes the fuel to microscopic proportions. This allows every cylinder to receive a precise, homogenous mixture of fuel and nitrous, thus insuring a safe, powerful increase.

A wet nitrous kit mixes nitrous and enrichment fuel by means of an injector nozzle that is mounted before the throttle body. This mixture is then drawn into the engine through the throttle body and intake manifold. A "dry" nitrous kit injects only nitrous with it’s injector while at the same time, increasing the engine’s fuel rail pressure to feed enrichment fuel through the engine’s own injectors.

[satch]

25-60 hp on late model EFI car -- Dry

75+hp on ANYTHING Wet !!!

[Robert56]

25-60 hp on late model EFI car -- Dry

75+hp on ANYTHING Wet !!!
Depends on what late model is, and what make. We ls1/ls6/ls2/ls7 guys easly run a 100 dry shot with no issues on stock cars ie: vettes, GTOs, f-bods and trucks.
Buy the way, the NX descript is flawed, imo. If someone wants me to elaborate I will. Also, NX is now not as opposed to a dry kit and has one in development.
Robert

[srsnow]

I would like it if you elaborated. It never made any sense to me how a dry kit would have uneven mixture but when you introduce fuel to the system all of a sudden distribution is no longer a problem. Gas is so much heavier than air or even nitrous I can't see how it could possibly have the same characteristics in side a manifold as something so much lighter. I always just attributed their logic to the fact that it was not something they offered so it made marketing sense to push the wet kits and try and discredit the dry kits.

[krazy4]

Dry shots on the 4.6 ford engines (plastic intake) seem like the way to go because of the puddling issue, but thats only if you spray to early. Hey i got a 4.6 with a cast manifold wet all the way. :D

[nxcoupe]

I would like it if you elaborated. It never made any sense to me how a dry kit would have uneven mixture but when you introduce fuel to the system all of a sudden distribution is no longer a problem. Gas is so much heavier than air or even nitrous I can't see how it could possibly have the same characteristics in side a manifold as something so much lighter. I always just attributed their logic to the fact that it was not something they offered so it made marketing sense to push the wet kits and try and discredit the dry kits.

I saw a flaw when he said what if an injector clogged? Well it woulf fry a cylinder whether the nitrous was dry or wet. You still need to enrichen the air that is entering the cylinder along with the nitrous.
You are correct, fuel is much heavier than nitrous or air, and it will not make some of the turns and twists in a late model EFI intake on some makes. A wet kit is easy to tune and work with, but distribution is just as much of a problem as with a wet kit, they are both throwing nitrous into the engine, but the wet kit throws fuel along with it. Logic would tell you if a cylinder isn't getting as much nitrous as the other cylinders, it is probably getting even less fuel than it should.

[The Racer's Edge]

I'm personally not really big on dry kits, i know people will disagree with me because they have used them with good results. How ever they due have a limit to the power they can produce safely, now you have to keep in mind that you donot want to over cycle your injectors trying to compinsate for the lean condition caused by they dry shot. Most dry kits increase the line pressure to compinsate but i have seen tunners increase the duty cycle of the injectors as well. It just makes for a more complicated setup, at least with a wet kit you can check the fuel flow at the solenoid and the jets, as well as installing a fuel pressure safety switch to keep things running smooth.
:rockon:

www.ShopTheRacersEdge.com

[DefEddie]

Dry kit's rely on the Mass Air Flow sensor to read the denser air coming in.A MAF work's by superheating a wire,and the airflow cool's the wire basically.The wire's voltage varies depending on the airflow going through,the ECM read's the frequency/voltage and add's fuel based on a table.
You can only go so high with a dry shot because the table's only go so high I guess...Personally I don't think it is safe at all for a dry shot,since your fuel would be dependant not only on a correct MAF reading,but also correct 02 and manifold pressure reading's..Like someone else said,If an injector is sticking or stuck then you've just lost fuel in that cylinder..And of course that mean's a lean condition,except since N20 is present the lean condition is much much worse....kinda like if your fuel pump goes bad on a wet shot..
If your using an aftermarket(granatelli,SLP etc.)MAF,DO NOT USE A DRY SHOT!!!
Aftermarket MAF sensor's(beside's being larger case)have a resistor built into the wire that lower's the voltage to the ECM.This cause the computer to lean out the mixture since it believe's their is less airflow.Aftermarket MAF sensor's are pointless if your N/A,cause your probrably not getting any restriction from the stocker..

Wet shot's have their own problem's,but are safer and more reliable then dry shot's IMO.A wet shot doesn't rely on the ECM for correct fueling,since you are adding the fuel it need's.It's also adjustable,whereas a dry shot isn't.If your running too lean then you can put in a bigger fuel jet,if your too rich you can put in a smaller fuel jet(hehe,or bigger N20)..So your fueling is dependant on YOU,not the ECM,which is effectively being tricked in a dry setup..
Of course you still have the fuel pump problem in both setup's,but a sticky injector won't mean catastrophic failure since technically it's running just as lean as it was before you hit the button...since your adding fuel AND nitrous it's only being suffocated by the amount of VE that is in that particular cylinder,which is substantially less then it would be if you had no fuel..
I didn't mention the fact that the pulswidth can max and all that stuff cause it was mentioned above.And of course a tuner can make a dry shot safer,but not everyone want's to spend that kind of money on a tuner just so they can change the size of their shot..
It's just safer for a wet shot,IMO a dry shot is almost pointless...and very dangerous...though it does work and of course can be safe when used correctly..

[srsnow]

Dry kit's rely on the Mass Air Flow sensor to read the denser air coming in.A MAF work's by superheating a wire,and the airflow cool's the wire basically.The wire's voltage varies depending on the airflow going through,the ECM read's the frequency/voltage and add's fuel based on a table.
You can only go so high with a dry shot because the table's only go so high I guess...Personally I don't think it is safe at all for a dry shot,since your fuel would be dependant not only on a correct MAF reading,but also correct 02 and manifold pressure reading's..Like someone else said,If an injector is sticking or stuck then you've just lost fuel in that cylinder..And of course that mean's a lean condition,except since N20 is present the lean condition is much much worse....kinda like if your fuel pump goes bad on a wet shot..
If your using an aftermarket(granatelli,SLP etc.)MAF,DO NOT USE A DRY SHOT!!!
Aftermarket MAF sensor's(beside's being larger case)have a resistor built into the wire that lower's the voltage to the ECM.This cause the computer to lean out the mixture since it believe's their is less airflow.Aftermarket MAF sensor's are pointless if your N/A,cause your probrably not getting any restriction from the stocker..

Wet shot's have their own problem's,but are safer and more reliable then dry shot's IMO.A wet shot doesn't rely on the ECM for correct fueling,since you are adding the fuel it need's.It's also adjustable,whereas a dry shot isn't.If your running too lean then you can put in a bigger fuel jet,if your too rich you can put in a smaller fuel jet(hehe,or bigger N20)..So your fueling is dependant on YOU,not the ECM,which is effectively being tricked in a dry setup..
Of course you still have the fuel pump problem in both setup's,but a sticky injector won't mean catastrophic failure since technically it's running just as lean as it was before you hit the button...since your adding fuel AND nitrous it's only being suffocated by the amount of VE that is in that particular cylinder,which is substantially less then it would be if you had no fuel..
I didn't mention the fact that the pulswidth can max and all that stuff cause it was mentioned above.And of course a tuner can make a dry shot safer,but not everyone want's to spend that kind of money on a tuner just so they can change the size of their shot..
It's just safer for a wet shot,IMO a dry shot is almost pointless...and very dangerous...though it does work and of course can be safe when used correctly..

This is not 100% true, while it is true that some of the newer cars (LS1) use this type of enrichment not all cars do. A large majority used a pressure bump. This is the most common style of dry kit for cars with return style fuel systems. Other older kits used flip chips (some L98 kits) while others are using the coolant temp sensor. The newer Mustangs and some other Fords as well use a pressure bump even though they are a return less system. They do this by truck the fuel pump into increasing its duty cycle. To say that all dry kits work in the same fashion, i.e. through the MAF can lead to confusion when some one is dealing with an older car that does not have the electronic to be able to compensate for the nitrous through the MAF alone. It can also lead people to think that you can't put a dry kit on a speed density car.

Also wet kits have the problem of the fuel being significantly heavier than the nitrous which can lead to distribution problems

[DefEddie]

Sorry,your correct
I had forgotten about raising the fuel pump duty cycle,though my personal opinion is that it's still a form of tricking the ECM...
The injector size/flow is directly related to fuel pump pressure,and the higher pressure the pump is pumping mean's your effectively raising the injector sizeing,duty cycle and flow..(ie..a 19pph injector at 43.5psi is a 24 pph injector at 50psi)That's just an example off the top of my head..
So the ECM is still being tricked into suppling more fuel..
Not to say it doesn't work,obviously it does it's job well or manufacturer's wouldn't sell them..
Most of my experience is based on LSx and L31 engine's,I'm a Ford Tech but have nothing at all to do with perf. modifying them..And all my experience with Nitrous is with Wet kit's...So I am biased in my opinion so take that into account.Just trying to put more info out there.

Did you mean Coolant temp sensor or Intake air temp sensor?

[srsnow]

Coolant temp sensor. That is how the NOS dry kits for a lot of the dodges work (Viper, Durango, Neon).

[The Racer's Edge]

Honda's seem to react to wet and dry setups because there intake sensor being in the manifold. A small note that i have seen a few times....

www.ShopTheRacersEdge.com
:drive1: