FAQ

FREQUENTLY ASKED QUESTIONS

1. How does nitrous oxide work?

A. The basic theory of how nitrous oxide works is simple enough: Nitrous Oxide provides the oxygen than allows an engine to burn more fuel, more burned fuel equals more power. Additional fuel up and beyond that required for aspiration is injected into the engine. This additional fuel, called "enrichment fuel", is the basis from which extra power is derived from the nitrous system. The quantity of the enrichment fuel determines the horsepower of the system. The fuel must be combined with sufficient oxygen for proper combustion. The oxygen is supplied from the nitrogen-oxygen compound known as nitrous oxide (N2O). During injection, the nitrous oxide enters the combustion chamber; heat from previous combustion disassociates the nitrous oxide into nitrogen and oxygen; the oxygen combines with the enrichment fuel for combustion and the nitrogen acts as a control (anti-detonate) during the combustion process.

2. How much of a horsepower increase can I expect from a NITROX INJECTION SYSTEM?

A. This depends on what you want to achieve. NITROX provides three levels of systems: NITROX STINGER; NITROX STINGER SS; and the Awesome Dual Stage NITROX STINGER DBX-II. If you are looking for a lake system, a good place to start is the hard-hitting NITROX STINGER with up to 120 horsepower output. Most of our customers, however, opt for the NITROX STINGER SS at 130 H.P. for example on a 2.5 Liter HP (260-300 H.P.) as a lake system. A good system for the 2.4 Liter Mercury would be a 110 H.P. system. Other examples are a 110 H.P. shot to an OMC V-6 Looper and Yamaha V-6 (158 C.I.) You will find the NITROX SYSTEM SPECIFICATIONS a very useful guide in determining which system is right for you.

3. What comes with a Nitrox Injection System?

A. A complete system consists of four components: Injection Module; Bottle Kit; Fuel Module; and Tank Kit. We do all the drilling, tapping, and proper placement of injectors. The kit is pre-plumbed and pre-wired; and, includes all the necessary switches, electrical terminals and connectors. The only thing you will be required to furnish is fuel line and wire. Our installation instructions are complete and simple to follow. There will be no trips to the hardware store searching for mounting screws, connectors or other installation hardware. THIS SYSTEM IS READY TO BOLT-ON AND BOLT-IN!

4. I was recently speaking with one of your customers and he said NITROX "flowed" all injection tubes. What's the big deal about this? Don't all manufacturers do this and if not, why?

A. During the drilling operation, the drill penetrates the injection tubes and invariably creates swirls and burrs. The burrs locate on the inside of the tube is the much same as experienced when drilling a piece of wood. Please remember, we are speaking of very small orifices and subsequent reaming may or may not dislodge this burr. We have noted flow rate variations up to 10%-12% on non-corrected tubes. Precise flow rates are the heart of a quality nitrous system. Most nitrous companies don't flow their injection tubes as for we have never witnessed a competitor's tubes that flowed to our standards. Customers with complaints of engine failure have sent us various manufacturers? tubes. Usually, it doesn't take long to identify the problem. Expense is one of the primary reasons most manufacturers do not flow their injection tubes. Unfortunately, correcting orifice flow simply isn't compatible with most modern production practices. (See question #12)

5. I've heard a lot about engine failures when using nitrous oxide on outboards. Is this true and what's the problem?

A. When used according to factory recommendations, shortened engine life should not be a concern. However, most failures can be traced to one or a combination of the following problems: (a) poor or ineffective system designs; (b) not informing the customer about all the equipment required for the proper safeguards; (c) expecting too much from the customer, who may not have the expertise required for a proper installation; (d) lack of precise flow standards as outlined in question #4; (e) backyard nitrous specialists who roll their own; tantamount, to do-it-yourself brain surgery--cheap, but, almost always fatal; (f) lack of sufficient fuel quality or fuel type for the power produced; and, finally, (g) manufacturers not taking time to properly educate and prepare their customers for success.

6. I've never run nitrous oxide. What's to keep me from screwing-up simply because I don't know any better? 

A. Great question. This question caused NITROX to sit down and do some soul searching. Nitrous is not magic; but the customer must be properly informed. With every system NITROX includes Service Bulletin #144, Outboard Nitrous Systems "DOS AND DON'TS" to help you along the way. Nitrox Support does not end when the system is shipped; Nitrox Technicians are available to assist and answer any questions.

7. I've got a nitrous system on my car. The manufacturer suggests turning back the timing and going to cooler spark plugs. What do I need to do to an outboard system?

A. That depends on the particular engine; whether it has built-in timing advance features, modification if any, fuel being used, and choice of enrichment fuel to be used. As long as a spark plug has the ability to provide adequate spark, a cooler plug acts as a little insurance in that it can eliminate a potential hot spot for detonation. Call for consultation.

8. Every time I've called to discuss a nitrous system Nitrox Technicians hit me up to use alcohol as the fuel to be injected with the nitrous oxide. I'd really rather run gasoline and I called another nitrous company and they said alcohol wouldn't work anyway. Can you give me the specifics?

A.  Nitrox makes some of the hardest hitting gasoline systems available. But when it comes to matching sheer power or dependability, the edge must always go to methanol. Gasoline-powered cars have never been competitive with their alcohol-fueled counterparts. (NOTE: The alcohol "Enrichment Fuel" is stored in a small auxiliary tank and is used only when injecting nitrous oxide. See questions #16 and #21.) There is something to be learned here. First, there is more power in utilizing alcohol; secondly, what would be maximum power levels for gasoline would be reduced and at somewhat safer levels for methanol. This is true even if you utilize the very best racing gasoline. The cooling effect of methanol is almost 3-1/2 times that of gasoline and all engines are subject to "thermal" limitations. If you still wish to use gasoline as an enrichment fuel, Nitrox will build a system to your specifications. Nitrox literally has hundreds of satisfied customers using methanol as an enrichment fuel.

9. I have a racing engine that is running on alcohol and it really makes the power. I understand you fellows use a lot of alcohol. Can we set-up to inject nitrous oxide and alcohol on top of the alcohol I'm already using? 

A. Although NITROX pioneered the use of alcohol as an enrichment fuel, I'm afraid that the results would be less than desirable. Nitrous oxide is extremely cold when injected. The alcohol you are currently using also has tremendous cooling power. You have probably noted the condensation on your intake manifold after a run. This attests to the frigidness of the incoming charge. If you again, lower the temperature by the injection of even more methanol, the charge becomes so cold and dense it is almost impossible to properly ignite and combust. My suggestion would be to inject gasoline as an enrichment fuel; it will act as an accelerant. Also, gasoline will do wonders for cleaning up the alcohol engine on the bottom end.

10. I contacted another nitrous company and they're pretty cheap when comparing prices. Why should I pay more for your system? What I mean is, do they have solenoids and injection tubes just like you do?

A. First, let me say regardless of which company you choose, nitrous oxide remains the most bang for the buck. Please do not hunt bargains in nitrous systems. Buy the best equipment and technical expertise you can find. Our abilities are evidenced by our sales. Approximately 75% are either repeat sales or direct referrals from our customers.

11. What's the best way to mount the nitrous activation switch? 

A. A good method to mount the activation switch is to install a switch on a Hydro Dynamics' footrest at the left foot. This does away with the dangling wires at the steering wheel. Another method is to employ a switch under the petal of a Hydro Dynamics' foot throttle. By using a small mounting bracket under the petal (furnished with system), the nitrous is activated as the engine is brought to wide-open throttle. The absolute best method is to utilize both methods. Mount one switch under the petal routing a positive wire through the switch, continue to run the positive wire to the other switch located at the footrest. From this switch continue the wire to the solenoids. This method offers you the best of both worlds. It allows the instant system response favored by racers who employ the under the petal switch; but, also allows you to disengage the nitrous and still retain wide-open throttle position. Another benefit is it insures that the nitrous will only be activated at wide-open throttle; and in the event of rough water conditions, this assures you're off both the gas and the nitrous.

12. I recently spoke with one of your competitors and he said "flowing" the injection tubes orifices was a waste of time; that he had enough "EFF" for a safe system. What did he mean by "EFF" and isn't flowing truthfully a waste of time? 

A. The excess fuel added beyond that required for a chemically correct mixture is called the EXCESS FUEL FACTOR or EFF. Most car systems run a 20-90% EFF. This works rather nicely for 4-cycle engines with their lean fuel mixtures. This is where problems can start. On automotive engines, you can get a little sloppy on jetting by simply throwing enough EFF to counter jetting irregularities. Since automobile engines are lean they make good power with relatively fuel-rich injection mixtures. A 2-cycle engine starts with a fuel-rich mixture. When you inject it with a super-rich mixture it kind of sputters and falls on its face. At this point, you are forced to start leaning the mixture by reducing the fuel pressure going to the injector. With the relatively small margins of EFF that are required for the 2-cycle, it doesn't take long to find those fuel orifices that aren't up to proper standards.

13. One of the guys that races in one of the Racing Associations recommended NITOX for a nitrous system and said to be sure and get a "Wash-Down" option installed. Could you explain what this is and how it works?

A. The "Wash-Down" feature is a NITROX exclusive and its use may be best illustrated by one of the drag boats we sponsor. This engine can exceed 11,000 RPMs in a quarter-mile pass. This engine produces over 500 HP from a Modified 2.5 Mercury HP utilizing a dual stage Nitrox nitrous system. At the end of the run, the engine is consuming unbelievable amounts of gasoline and methanol. If the driver simply disengages the nitrous system, residual heat in the engine will cause seizure in 1-3 seconds. "Post Injection Leanness" is a real problem that must be dealt with in the 2-cycle engine as it relies on the incoming charge as a source of engine coolant and lubrication. A Wash-Down feature is an uncomplicated arrangement by which you employ a second switch that energizes only the fuel solenoid for 1-1-1/2 seconds after injection has ceased. Whether you need a Wash-Down depends on various factors. In principle, total horsepower output is determined by the volume of heat being produced, the combustion temperature (leanness), and the duration of injection. Post injection leanness can be observed and evaluated by the use of a pyrometer (see question #20). Most stock or near-stock V-6 engines in the 200 HP categories can tolerate 110-130 HP on alcohol-enriched injections without the use of a Wash-Down Option.

14. I run another brand of nitrous system and one of the fellows I drag race against uses your system. He really kicks butt coming out of the hole. He said it was because he used the "Lean-Burn". What is it? Will you make me one? 

A. "Lean Burn" is a NITROX innovation. I will tell you how it works; but please understand that we cannot install it on a competitor's system. An outboard relies on a super-rich fuel mixture to keep it idling. This is imperative because of the great overlap between intake and exhaust port timing. Prior to leaving the starting line, the engine is very cool and has an over abundance of lubrication. To a degree, all 2-cycle engines must "clear-out" before being able to come to full power. At this moment, for a short duration, if you inject a very lean mixture of nitrous oxide and enrichment fuel, the results can be extremely impressive, as you have most probably noted.

15. I'm currently running the oil injection unit that came on my engine. I would like to keep it on, that's ok isn't it?

A. Unfortunately, the answer is no. Most of us are already running our hi-performance outboards above the manufacturers' suggested RPM. You are asking for more performance, which means increased RPMs. Manufacturers' representatives feel that around 6700 RPM is the maximum you can reach before oil leaning can occur or over a period time, pump failure. The factory performance engines, most of which are not available in oil-injected models, further substantiate this. Our only alternative appears to be the traditional blending of oil and gas; however, this doesn't have to be that bad. By using a Hydro Dynamics' mixing cup all that is required is to fuel the tank up; note the number of gallons of fuel; and, fill the mixing cup with oil to the point which reflects how many gallons of fuel was used to fill the tank.

16. I want to run pump premium like I'm running now and inject nitrous. I understand you can do this if you inject alcohol; but do I inject the alcohol through my regular fuel system or what? 

A. No. The nitrous system is independent of your present fuel system. Your motor runs just as it does now. However, when you wish to inject nitrous oxide, you must inject additional fuel into the engine as a basis for power. (See question #3) The alcohol is supplied by its own fuel pump and tank. One of the appealing features about Nitrox Injection Systems, compared to other methods of performance enhancement, is that it's power on demand and that is a lot to be said. Your engine doesn't have to deal with the heavy compressive loads that a modified engine must always deal with. You don't have to run expensive fuel or put up with the idiosyncrasies that some modified engines exhibit. At resale time, you can remove the nitrous system and the stock engine sells faster and at a better price.

17. I'm not going to modify my engine; but install a big nitrous system. If required, I can just up the system's power and I should be able to handle about anyone that comes along. Is there any thing wrong with this approach? 

A. The power gains available using a stock powerhead and nitrous sometimes appear to be nothing short of incredible. You will succeed with this approach until you run against a modified powerhead with a similar nitrous system. At this point, you lose. Regardless of how much nitrous/fuel mixture you inject into the front half, if the intake porting area and the exhaust area are not sufficient to ingest and expel the charge, then you're going to run against a wall. Admittedly, acceleration will become more pronounced with each increase; but once again, you run against the wall. Modified power heads with improved port timing and exhaust relief simply have greater intake and exhausting capabilities. On some engines, the "wall" is not the exhaust, but the intake port area. There's not enough available intake time/area to maximize the incoming charge. Continue on with your present plan; but, be sure and order the NITROX STINGER SS System. With its large solenoids you can develop some impressive horsepower. You will be formidable without the improved porting. Later, if the need arises, give us a call about porting and exhaust relief.

18. I have run a nitrous system before and while I thought the power was awesome, I continued to have trouble with the solenoids "sticking". If I decide to buy a system, what assurances do I have that I won't encounter this problem again? 

A.  I really don't know how long ago you purchased your system; but most of the inferior solenoids have been weeded out. All the nitrous companies, that we are aware of, provide excellent quality solenoids. What many fail to do is add a nitrous filter as part of their system. Invariably, what happens is a minute piece of debris gets stuck in the "seat" and its sealing surface resulting in a nitrous leak. We recommend changing the N20 filter, the enrichment fuel filter, and the engine fuel filter at the beginning of each season. The large "fill" bottles are generally steel cylinders and always have rust in them. Some refillers fail to install filters on their nitrous transfer lines allowing debris to transfer into your bottle during the filling operation. One of the first things I would look for if the system loses power would be a clogged nitrous filter.

19. One of my buddies runs a fogger type nitrous system on his drag car. He said that's the only way to go. In your literature, I see you have injection tubes; but it didn't mention any of the "fogger" style injectors. Can you install them and aren't they better? 

A. Fogger style nozzles are fine injectors; and, sure we do these too. First, let's place them in proper prospective. Automotive systems are generally "Plate" or "Fogger" type design. The plate system consists of a N20 injection tube mounted on top of a fuel delivery tube in an injection plate. The plate is placed between the carburetor and the intake manifold. The injection mixture is atomized and injected into the common plenum area of the intake manifold. Distribution takes place by the nitrous/fuel availability at the intake opening. These systems do, however, perform in a satisfactory manner but are usually limited to 300 HP. On an automotive fogger system, the individual injectors are placed in the runners of the intake manifold and in essence are "port injection". Tests indicate at lower power levels the plate and the fogger system are virtually identical in power output. At higher levels, the edge always goes to the fogger system. The primary reason is the uniformity in which the nitrous/fuel mixture is distributed. However, outboard systems differ in this regard: they share no common plenum (with the exception of Mercury EFI models) and they all effectively have individual intake runners, the distribution problem doesn't exist. On EFI models, or for that matter on all of Nitrox Outboard Systems, we install the injection tubes directly in front of the reed blocks. With this in mind, all outboard systems are effectively port injected. The exception to that would be the placing of one or two high output fogger type nozzles in the intake horn of a Mercury EFI. I found this to be a dubious practice because these nozzles are widely touted for their "directional" injection capability. Since this is true, aren't you directing the nitrous/fuel mixture toward whatever cylinders these injectors happen to be pointed? A much better way would be to install the injectors in the plenum box directly in front of the reeds. At this point, you realize you're right back where you started with the injection tubes. Our tests indicate no power advantages in using the fogger injector over the injection tube.

20. I understand your company offers a device that monitors exhaust gas temperature. Could you tell me a little about it? 

A. Yes, we market this item and it is called a Pyrometer. Nitrox/Hydro Dynamics offers two types of pyrometer kits: Dash Mounted (analog) and the Mini Digital, which records the minimum and maximum, exhaust temperatures. The use of a pyrometer brings us out of the Stone Age as for as jetting a 2-cycle engine. One of our customers recently called and told how he had made the "cut" during the first round of a double elimination boat race. He had lost to the lead boat by two boats lengths; but noted that his exhaust temperature was down. He usually ran at sea level; this race was taking place at a higher altitude. He reasoned that the altitude had richened his engine. During the interval between rounds, he leaned the engine by a couple of points. Not only did he make up the two boat lengths; but gained another to win his class. Our primary use of a pyrometer is in conjunction with a nitrous system. After installing a nitrous system, it's interesting to first make a pass without the nitrous system, and then make one utilizing the system. The idea is to keep the exhaust gases actually a little cooler on the button than it is off the button. During the run, if you observe system temperatures are too "rich", you can lean the system by reducing the fuel pressure at the injection pump. One should bear in mind, that the reading reflects the combined temperatures of one bank of the engine when using a single read pyrometer; and, of course, both banks if using a dual read pyrometer. Obviously, the reading of the combined temperatures of a bank does not necessarily guarantee that all the cylinders within that bank are of a uniform temperature. The best bet is to remove the spark plugs from the bank noting the uniformity of color from one piston to the next. Trying to read surface gap spark plugs is an exercise in futility. Surface gap plugs by nature are so cold that achieving anything resembling the proper cardboard brown coloring on the insulator will most likely result in a seized piston. When jetting a Mercury engine, a spark plug such as a NGK BR9HS-10, the plug color will be indicative of what's really happening in the combustion chamber. However, do not extrapolate this to mean this would be true in an OMC Engine. The only way to jet an OMC is to read the pistons. Remember, most engines run hotter on some cylinders than on others. NITROX is aware of this condition and we compensate with the output of the fuel orifices for these hot cylinders.

21. On my 21' Cougar, I run dual 2.5 EFIs. Since I've decided to run methanol with my nitrous system, am I required to use two of the small 3-gallon tanks and two of the injection pumps? 

A. No, I would run one tank and one injection pump. I would recommend going to the larger 6-gallon tank kit. By utilizing a NITROX Fuel Module and a distribution block, you can supply enough fuel for dual STINGER system. For readers who run triple or quad engine systems, you can select a fuel module that utilizes twin race pumps that feed oversize fuel distribution block. The 1-/4" red anodized block utilizes a 3/4" interior bore and provides plenty of fuel with 3 or 4 output fittings. Generally, the supply for the dual pump module is accomplished by the use of twin tanks. In the event only one tank is desired, an 8-gallon racing fuel cell is available.

22. I have friends that use your systems and they have never had any problems. I have to confess; I'm still a little scared because I've seen the power these systems can produce. Is there any way I can play it safe; say with a small system?

A. Your dilemma is not an uncommon one and I'm glad you were honest about it. Let's start at square one. Most nitrous troubles begin with the problems I've outlined in previous questions and usually comes back to one of two things: thermal problems caused by too lean mixtures or insufficient fuel quality to do the job. Go with methanol as an enrichment fuel. This will take care of the fuel problem. I've seen people get by with some pretty incredible things with methanol. Secondly, instead of going with a small system, go ahead and get an intermediate power level. You can control combustion temperatures by the amount of fuel pressure you inject with the injection module. Our philosophy has always been, when in doubt, inject a larger charge and combust it at a cooler temperature. This obviously is preferable than a smaller charge at higher temperatures. I cannot help but think of one customer who chooses to run his system overly rich. The system is so rich that nearing the end of the quarter mile mark the engine will actually begin to load-up and start to four stroke. I constantly nag him to lean the system down; his reply is always the same.... who was ahead at the end of the race and who's not working on their engine this weekend? I really can't disagree with that philosophy. He has six seasons on the nitrous system on an eight-year-old motor that's raced every weekend of each season.

Frequently asked questions compiled and answered by Chuck Goodman