dry vs wet test

[mrr23]

yeah, i'm at it again. been seeing too many which has a bigger hit dry or wet posts. so, i'll be picking up a dry nozzle from ny-trex. has a .125 orifice through it. it'll be a 100 shot test. so, who wants to see it?

[Nate]

i do i do....do you need a good camera?

[mrr23]

i bought a new camera. a 6MP with a macro button for close ups. no blurry pics this go around.

[Nate]

sweetness.

[YenkoST]

I would be interested in seeing this....I am debating what is better for my application. I am leaning toward the dry just b/c of the backfiring issue in the intake. Thanks for doing this test!

[mrr23]

i wouldn't worry about the backfiring thing. with my HSR on my 86TA, i never had a backfire on the 150 shot.

but, if you did do the dry shot, i would suggest the NOS05176 kit for the LT1 motor. comes with an inline fuel pump. you run a line from the solenoids to the regulator to shut it down to increase the fuel pressure.

[Nate]

What's the latest on this test?

[mrr23]

www.centralfloridastreetcars.com/dryvswetnitroustest.htm
i started making a webpage. still need to install the dry nozzle and get a hold of a dyno location. will most likely get this done in about 30 days.

[mrr23]

having some discussion on where to place the nozzle.

here's my thoughts on where to place it. red his, blue mine.

http://www.centralfloridastreetcars.com/nitroustest/drynozzleplacement.jpg

[lxh89]

With the dry kit, I would place the nozzle as far down the intake tract as possible to take advantage of the cooling effect. I am not sure how you plan to enrich it whether through higher fuel pressure or tricking the mass air, but for a good comparison, keeping the air/fuel ratios close will give a better comparison.

My own personal belief is there will be very little difference. Depending on the intake, the dry may offer an advantage as the extra fuel is provided by the injector which we know does a good job atomizing.

Tony

[mrr23]

what i was planning on doing was do the dry runs first. then, do a baseline jetting run for the wet. if the a/f ratio doesn't match, then jet the wet kit to match the dry kit reading.

[Robert56]

having some discussion on where to place the nozzle.

here's my thoughts on where to place it. red his, blue mine.

http://www.centralfloridastreetcars.com/nitroustest/drynozzleplacement.jpg
If you use the blue location it should be dual straight nozzles, one across from the other. The reason this is done is the fact that the to streams will meet in the middle and create a null area and mix well with incoming air (like the 5177 NOS). this location normally produces a lean a/f and going into computer and uping your PE fuel multiplier is an easy answer amongst about a 1/2 dozen ways to add extra fuel.
The red location is much bette for a 90* nozzle. The MAF will read a much colder denser mix and allow the computer to automatically compansate with a higher injector duty cycle. Actually there will likely be a rich reading at this spot but this is good. the reason it's good is the fact now you can adjust your a/f to desired ratio by just turning nozzle up or down. Whereas, the above location you must retune inside the computer and this can affect n/a performance.
I also believe a dual nozzle dry set-up will give a better pattern over the maf compared to a single nozzle, and thus a more complete and accurate reading.
Here is a picture of my set-up. I run quad nozzles in a dual stage. They are approximately 3 inches from MAF and I have gone up to a 200 shot. I use 3 straight nozzles and one 90* nozzle. Until I added the 90*, the mix was running a tad lean. Through the nozzle location I was able to do all my a/f tuning and now run about 11.5/11.7 area and have not affected my n/a a/f.
http://home.comcast.net/~weaver.robert/wsb/media/779908/site1060.jpg
Robert

[Helmsdini]

you KNOW I want to see this test.

I have extensive experience with both kits, but since the dry kits are a little more difficult to understand, I more or less specialized in them. I will say from first hand experience, wet kits hit MUCH harder initially, wich isnt really a good thing from a parts breakage and traction standpoint. Mike at NX claims they have seen an almost 50% reduction in torque when comparing dry kits to the wet kits.

I dont know what the outcome will be myself, but im biting my nails to see this done.

[Robert56]

you KNOW I want to see this test.

I have extensive experience with both kits, but since the dry kits are a little more difficult to understand, I more or less specialized in them. I will say from first hand experience, wet kits hit MUCH harder initially, wich isnt really a good thing from a parts breakage and traction standpoint. Mike at NX claims they have seen an almost 50% reduction in torque when comparing dry kits to the wet kits.

I dont know what the outcome will be myself, but im biting my nails to see this done.
Yes, in the torque spike catagory, however, the peak torque will be much closer. I am running head to toes with a dry 130/140 to guys running 150 wet hits. I can get the power to the ground and cut much better 60'ers, now remember, I am talking true street/strip cars, and not the mondo launching wheels in the air f-bodys. But I agree with what you said/state.
Robert

[mrr23]

then the red marker it is.

[Helmsdini]

Yes, in the torque spike catagory, however, the peak torque will be much closer. I am running head to toes with a dry 130/140 to guys running 150 wet hits. I can get the power to the ground and cut much better 60'ers, now remember, I am talking true street/strip cars, and not the mondo launching wheels in the air f-bodys. But I agree with what you said/state.
Robert


yeah, and that is the debate I have been in with Mike Wood at NX before. Mike is a great guy, but we obviously have our different theories. He claims the 50% reduction in torque deal, and I basicly dont buy it. I think that you can probably physically RUN better times with a dry kit, simply because you dont have near the driveline shock, just as you stated. If you are talking about pure dyno numbers, then that is a different story, but as we all know dyno rollers dont win drag races.

If its any console, when I asked mike about the dry vs. wet test that NX did, he only told me about the lower torque out of the dry kit. He didnt give me an in depth overview of what actually happened, because im betting the overall HP measured was very very close.

I have spoken with you on the corral before robert, My name over there is Supernatural. Nice to see you around, and it looks like your business is really taking off!

[Robert56]

Yea, I think I remember the supernatural. heven't been over to corral in a while. ;) I have a dyno sheet to prove what a dry can do to help a stockish car save the rearend, trans and engine, and also allow hooking up for nice 1.5x's. furthermore, killing most of the "all in one torque monster spike hits", whom can't seem to get a good 60'er cause they have to pedal it outa the hole. I will post more later, and have my 10.xx slip posted on an absolutly bone stock long block, not even headers (soon).
Robert

[Helmsdini]

You sell cold fusion products through your business, correct?

Im starting to do some research as to why those through-the-maf dry kits havent taken off with the 5.0 crowd the way they have with the LS1 guys. It may have something to do with the electronics on the car, but if that is the case I should get a bunch of horror stories from the 5.0 crowd.. and I havent heard any yet.

I run a tweecer on my car, so I can adjust the MAF curve for a through the maf dry kit, but I see no reason why these kits wouldnt be just as effective on the 5.0 cars as they are on the LS1's

[mrr23]

more pics are up on the webpage.

[lxh89]

Here's my own early testing of a NOS 5115/5116 kit on my 2003 Mach 1. Some points to consider, this is a NOS 5115 kit using a NOS 5116 fuel enrichment module. Since the module was calibrated on a GT with 19lb injectors, weaker fuel pump, you can see it's running pig rich. It's off the chart on that dyno, but with my wide band, I was seeing around 8.8:1 on a 53 nitrous jet (roughly 120 shot @ flywheel or what NX calls a 100 shot-52 jet). Around 5500rpm it starts coming to 11:1 A/F as the BSFC of the engine increases thus demanding more fuel.

As you can see, it shocks the piss out of the dyno and artificially spikes the torque to insane numbers but then levels out. The run that registered 407rwhp and 558rwtq was the .53 jet. The previous runs were .42 jet, engine cold, 950psi bottle pressure. The next highest was a .47 jet, engine heat soaked, 800psi bottle pressure.

Anyways, the point I was getting to is, this dry kit performs well. On the .53 jet, I dropped my best time from 12.56@107.42 on motor to 11.63@117.1 mph (DA less than 100ft difference). That's spot on if not better than expected results.

Now, considering it's running so rich, I have done a bit of tuning with a mustang tuning tool and upping the nitrous jet. I currently have a .63 jet in and on the street doing 3rd gear pulls I see around 10.2:1 A/F in the begining which leans out to 11.5:1 in the upper rpms. The car is a monster on the 150 but unfortunately I haven't got any good times with it yet. I am waiting for the good weather! In 4500ft DA air, it went 11.63@118.79mph on the 150 shot. Only 2 mph increase in trap speed over the .53 jet, but the air was basically a mile higher too!

I am rooting for the dry shot to deliver equal if not better power than the wet shot due to superior fuel atomization (the fuel injectors win against any fogger nozzle) and more equal distribution among cylinders (safer). And by wet shot, I don't mean a noszle kit, fogger kit where it injects fuel/n20 in each cylinder. I am talking about the typical single fogger nozzle wet kits.

Tony

[Helmsdini]

Nice numbers, tony!

The rich issue with that kit is inherent when using the 5116 fuel module. The 5115 kits were a little easier to tune because you could simply use the adjustable bypass tee to adjust fuel pressure if needed. Nice to see another NOS dry nitrous guy. Check out my website if you get a chance.

anyway, I just wanted to address a couple points you made. Dry kits typicly have a poor cylinder distribution when compared to wet kits. This fact alone is why Mike Wood at NX feels that wet kits are the only ones worth using. Basicly what happens, is that since no two intake runners flow exactly the same ammount of air, different amounts of nitrous are injected into each cylinder, but since the fuel is added via a metered fuel injector pulse, the fuel injected is the same across the table. This becomes a real issue on very large dry shots. We had a problem getting all of the cylinders on the safe side, but not overly rich much above 200 HP.

The other point is about the fuel atomization. Believe it or not, a wet nozzle does a better job atomizing the fuel for nitrous. The basic reason for this is that wet nozzles use the nitrous to aid in atomization. The nitrous oxide is injected at 1000 PSI, and above all other factors, pressure is the main culprit in atomization.

Now that I have defended the wet kits enough, there are alot of benifits to using dry nitrous, such as you simply dont have raw fuel traveling down an intake that wasnt made for wet flow in the first place. I honestly think it will be a toss up myself. Alot of the theory is that since all dry kits go from an overly rich cylinder condition to a lean condition, the initial "hit" isnt as hard as a wet kit is because they generally go from slightly lean to rich. I think overall, the method that the fuel is injected will prove to be an almost moot point, and really that is the only difference in wet vs. dry nitrous. Both get plenty of nitrous and fuel to the cylinders, its just the fuel supply method that differs. I think as long as the kit is working as it should, the HP difference should be slim to none, and this is reflected by looking at nitrous jets for both wet and dry kits as they are generally almost exactly the same.

[lxh89]

anyway, I just wanted to address a couple points you made. Dry kits typicly have a poor cylinder distribution when compared to wet kits. This fact alone is why Mike Wood at NX feels that wet kits are the only ones worth using. Basicly what happens, is that since no two intake runners flow exactly the same ammount of air, different amounts of nitrous are injected into each cylinder, but since the fuel is added via a metered fuel injector pulse, the fuel injected is the same across the table. This becomes a real issue on very large dry shots. We had a problem getting all of the cylinders on the safe side, but not overly rich much above 200 HP.


Yes, I am familiar with that statement regarding poor cylinder distribution. Wouldn't that statement be more profound with a single nozzle wet kit on a modern EFI engine since the intake's were designed strictly for dry flow only? I am sure as rpm increases, fuel suspension issues disappear, but at lower rpms, it could present itself as certain cylinders running leaner than others.

Depending on the flow variance between intake runners, I am sure a port job taking special care to insure even flow would overcome that argument. I think I would also argue with my particular application, there isn't a large variation among runners like there was with the 5.0L intakes specifically the stock intake.



The other point is about the fuel atomization. Believe it or not, a wet nozzle does a better job atomizing the fuel for nitrous. The basic reason for this is that wet nozzles use the nitrous to aid in atomization. The nitrous oxide is injected at 1000 PSI, and above all other factors, pressure is the main culprit in atomization.



Yes, I can see that from a pressure perspective; however, does the nitrous/fuel mixture stay together in good proportions as it weaves its way through a modern EFI intake? Same point as above. Also, how does the supercooling of the gasoline affect its ability to combust properly AND stay atomized. It's known that a finer atomization results in more complete combustion which is why the future for gasoline fuel injection is direct injection ala diesel style with fuel pressures reaching over 1,000 psi.


Now that I have defended the wet kits enough, there are alot of benifits to using dry nitrous, such as you simply dont have raw fuel traveling down an intake that wasnt made for wet flow in the first place. I honestly think it will be a toss up myself. Alot of the theory is that since all dry kits go from an overly rich cylinder condition to a lean condition, the initial "hit" isnt as hard as a wet kit is because they generally go from slightly lean to rich. I think overall, the method that the fuel is injected will prove to be an almost moot point, and really that is the only difference in wet vs. dry nitrous. Both get plenty of nitrous and fuel to the cylinders, its just the fuel supply method that differs. I think as long as the kit is working as it should, the HP difference should be slim to none, and this is reflected by looking at nitrous jets for both wet and dry kits as they are generally almost exactly the same.

I agree.


I will also add, a particular topic of recent interest for me is propane/nitrous injection. It obviously shares the shortcoming of a wet kit where you have a larger volume filled with nitrous and fuel vs a dry; however, I think it would result in better combustion because propane is a gas so atomization is moot. Basically mixture is more important for even combustion. Also, propane is high octane so less need for timing retard.

I really wish more companies would investigate alternate fuel usage with nitrous kits. I can see some real benefits over contemporary gasoline in race environments.

Tony

[Helmsdini]

Very good points about the main drawback of EFI single nozzle nitrous kits.. the fact that the intake wasnt designed to have fuel particles flowing through it in the first place.

The dry nitrous distribution issue is probably blown out of proportion, just as you mentioned. All I can attest to is that it starts creating big problems when you go much above 200 HP out of a single dry nozzle. The wet kits... well we dont know just how high those intakes will go out of a single nozzle, because of the basic phenomenon you just mentioned.

On our 5.0 engines we were having issues above 200 HP with a single wet nozzle actually saturating the intake charge with so much fuel and nitrous that it was forcing the very cold fuel OUT of suspension, and collecting on our runners. This would pop the intake almost every single time, because the incomming air charge was lean and the intake was coated with gasoline. The fact that the intake will usually blow before the charge gets to the cylinder runners make the wet kits "generally" more even at distributing from cylinder to cylinder. A dry kit wont blow like that, but it will usually melt pistons when this phenomenon presents itself... so the more I think about it there is a good possibility that you are onto something with that theory. Very good points.

I also wanted to ask you if you had a schematic for that 5116 fuel pressure module. I have been thinking about trying to install a rheostat type system, that allows an adjustable voltage to be applied to the fuel switch, perhaps allowing tunability of the system just as the older 5115 kits can use.

[lxh89]

Very good points about the main drawback of EFI single nozzle nitrous kits.. the fact that the intake wasnt designed to have fuel particles flowing through it in the first place.

The dry nitrous distribution issue is probably blown out of proportion, just as you mentioned. All I can attest to is that it starts creating big problems when you go much above 200 HP out of a single dry nozzle. The wet kits... well we dont know just how high those intakes will go out of a single nozzle, because of the basic phenomenon you just mentioned.

On our 5.0 engines we were having issues above 200 HP with a single wet nozzle actually saturating the intake charge with so much fuel and nitrous that it was forcing the very cold fuel OUT of suspension, and collecting on our runners. This would pop the intake almost every single time, because the incomming air charge was lean and the intake was coated with gasoline. The fact that the intake will usually blow before the charge gets to the cylinder runners make the wet kits "generally" more even at distributing from cylinder to cylinder. A dry kit wont blow like that, but it will usually melt pistons when this phenomenon presents itself... so the more I think about it there is a good possibility that you are onto something with that theory. Very good points.

I also wanted to ask you if you had a schematic for that 5116 fuel pressure module. I have been thinking about trying to install a rheostat type system, that allows an adjustable voltage to be applied to the fuel switch, perhaps allowing tunability of the system just as the older 5115 kits can use.

Unfortunately I don't know how it ticks internally as I didn't have the guts to explore mine considering how much it costs. However, I would wager it's a simple resistor and a rheostat could be used to "dial-in" the pressure.

I do know, however, the Ford has engineered the returnless fuel system such that if it detects zero fuel pressure, it will trigger a fault if the engine is running. You would need to be careful with the rheostat as ultimately you are fooling with the fuel pressure sensor signals to the computer. By lowering what is measured, the EEC increases the fuel pump duty cycle to compensate.

My own thinking on fine tuning this was to incorporate a device to control fuel pump voltage. I know that the 5116 module causes the fuel pump to operate at 100% duty cycle. If you can control the voltage, you ultimately control the flow. I don't know how difficult it would be to create such a device. The Kenne Bell Boost pumps only appears to offer same voltage or voltage increases and not the ability to reduce.

Perhaps someone handy with electronics could propose a simple solution?

Tony

[Helmsdini]

Ill keep my eyes open for one of the modules on ebay and see if I cant play with it some if I get one.

so, basicly all that module does in effect is tell the computer that the fuel rails arent getting enough pressure, so the EEC increases the pressure at taht point. I would imagine that with some sort of modulation, it would be easy to adjust the amount of "lowered" pressure the EEC is seeing, and thereby make the kit adjustable in that aspect. Good info about the 0 PSI thing as well, because that will have to be taken into consideration for the upper limit.

You are correct about the BAP system. it only increases voltage up to 18 volts. it wont decrease it any lower than 12. I have one that I will probably install on my car instead of using a secondary pump for the bigger shots.

[lxh89]

Ill keep my eyes open for one of the modules on ebay and see if I cant play with it some if I get one.

so, basicly all that module does in effect is tell the computer that the fuel rails arent getting enough pressure, so the EEC increases the pressure at taht point. I would imagine that with some sort of modulation, it would be easy to adjust the amount of "lowered" pressure the EEC is seeing, and thereby make the kit adjustable in that aspect. Good info about the 0 PSI thing as well, because that will have to be taken into consideration for the upper limit.

You are correct about the BAP system. it only increases voltage up to 18 volts. it wont decrease it any lower than 12. I have one that I will probably install on my car instead of using a secondary pump for the bigger shots.

Since we are dealing with a returnless system, excess fuel not consumed by the engine results in pressure increase. Obviously the amount the pressure increase is directly proportional to the strength of the fuel pump to counter the pressure spike. This is how the eec maintains the proper amount of fuel pressure at the injector is by fuel pump duty cycle. It appears that Ford has intentionally oversized the fuel pump to account for weakening over time so in most operation conditions on a stock car, one would never see over 80% duty cycle at the pump.

Anyways, when the fuel rail pressure sensor reports back a lower value than required to meet the needs of the engine at that mount, it raises the duty cycle until that need is met. Obviously this check and adjustment occurs very quickly. The fuel pump duty cycle is controlled via a "pulsed" ground. In other words, if it commands 50% duty cycle, it pulses the ground such that in a one second time frame, the ground is available 50% of that time period.

If we added a stronger fuel pump to this system, it would likely result in more pressure at the rail when the pump is forced to 100% duty cycle.

Hope that explains the Ford returnless fuel system. Obviously I explained that loosely but in principle that is what happens.

Tony

[Robert56]

Here is a quick run down on the Nitrous Direct 'Ultimate PRO Dry' kit we have been working on. It's based on NX Lighting Stage 6 noids and CF ss dry nozzles amongest other goodies. first time dyno on and absolutely bone stock longblock produce 550rwhp and 636 torque. this was in dual stage mode, actually the highest torque was from the 170rwhp 1st shot. i will be doing a full write up of this and post in a new thread. I might add that a buddy's head and cam C5 with a competitors plate kit jetted at 200rwhp fell short by more than a margin in the torque department and only got me by 9hp in the power dept. So, dry can be a wet killer and I will put this kit up against any wet kit win/loose or draw. Will have track times next weekend. Have one allready, on a small single stg hit.
http://home.comcast.net/~weaver.robert/wsb/media/779908/site1088.jpg
Robert

[mrr23]

i should be getting this done on 11/18

[Robert56]

Ran a 10.85 @ 128.9 on my 3rd pass at 235rwhp dry on stock long block. Will post details later.
Robert

[mrr23]

well then, i guess i'll quit worring about my 100 dry and 150 wet not holding up. i did some small street runs and didn't see a pressure drop. then again, that wasn't a full 1/4 mile.

[Robert56]

well then, i guess i'll quit worring about my 100 dry and 150 wet not holding up. i did some small street runs and didn't see a pressure drop. then again, that wasn't a full 1/4 mile.
Yea, I also did two passes at 250rwhp shot.
Robert

[lxh89]

http://home.comcast.net/~weaver.robert/wsb/media/779908/site1088.jpg
Robert

Notice how when the fuel gets rich, the hp/tq increase? That kit would make a lot more under the curve if it were running around 10.5:1 A/F.

Tony

[mrr23]

you notice that his is a two stage system and you are seeing the 2nd stage coming on?

[mrr23]

well, here it is. personally, it shouldn't be taken with a grain of salt. basically, the dry nozzle is in the wrong place in the lid. MAF cannot get a good enough sample of the nitrous to add the appropriate amount of fuel. so, i stopped the test. again, IMO due to improper placement of the nozzle, i don't call this a fair test.

NA 282 rwhp 284 rwtq
100 dry 347 rwhp 362 rwtq gain of 65 rwhp
100 wet 405 rwhp 409 rwtq gain of 123 rwhp

on a good note, this is the first time i've ever gotten more than rated with the wet kit.

http://centralfloridastreetcars.com/nitroustest/drywet052.jpg

[mrr23]

the thing to look at is the curves of both. they practically mimmick each other the entire run. so, given that, if the dry would've put out the same rwhp number, i conclude they would be the same.

[nxcoupe]

Some good reading, but I am confused why the dry kit didn't get near the amount of hp as the wet. I took a wet plate off and put my dry kit back on with similar jetting and made similar hp. I don't think one makes more hp than the other, but I hope you can get the dry one dialed in more.

[mrr23]

for the LS1, it depends on the MAF to read the incoming nitrous to supply fuel. getting the nozzle in the right spot is critical.

[nxcoupe]

That makes sense then, and the mass air is critical in calculating load, so that would explain it. Are you going to play around with placement?

[mrr23]

not anytime soon.