There arrives a issue in your ability buildup where by you may possibly take into account adding nitrous oxide injection to your supercharged car. This position typically coincides with reaching a degree of overall performance that suggests amplified investment decision and diminishing returns from your supercharger. For illustration, my motor vehicle will come from the manufacturing unit with a 5th generation Eaton MP45 supercharger. This supercharger is confined to about 230hp worthy of of circulation rating and so no make a difference what I do with bolt-on updates on my motor, my peak horsepower will not exceed 230hp limit since that is the position at which the supercharger becomes the bottle neck in my method.
As we’ve talked about in earlier articles or blog posts there is continue to the alternative of porting the manufacturing unit supercharger for a 10 to 15% achieve in capability (which in this situation would be a different 23 to 35 horsepower). There is also the possibility of retrofitting a larger supercharger such as the Eaton M62 to acquire possible up to over 300hp based on the closing selection of a supercharger.
This modification path (porting or changing the manufacturing facility supercharger) can establish to be sophisticated and pricey, particularly if the supercharger is built-in into the intake manifold (and quite possibly an air to water intercooler) as the circumstance is with quite a few manufacturing facility supercharged cars and trucks.
A achievable feasible answer for this predicament is to use nitrous oxide injection to supplement the electricity shipping when racing, and remaining happy with a trusted lower powered motor vehicle when the nitrous is off and we’re not racing.
The purpose why nitrous oxide (N2O) becomes a terrific energy adder is twofold:
1- Nitrous is inexpensive as far as horsepower for each greenback goes, and specially in the predicaments exactly where we are now supercharged and so will only be making use of it on the uncommon situations when we do hit the observe.
2- Nitrous oxide is a excellent ‘chiller’ as it comes out of the bottle at a temperature of damaging 127*F and is able of cooling the over-all supercharged air charge mixture by over 100*F as claimed by fans, this is an further temperature reduction around the results of no matter what intercooler you have equipped. This in-point can make nitrous a excellent proposition for cars that have by now maxed out their superchargers, where by the supercharger is operating at peak rpms and creating pretty high outlet temperatures. The nitrous oxide injection can properly boost the thermal performance of the supercharger when it is most stressed out and give us a pleasant, great, and dense mixture.
3- Nitrous oxide fuel shipping and delivery is reasonably straight forward to setup and to tune, particularly on newer design vehicles with return-les gas techniques, or tricky to crack computer systems that make it complicated to upgrade (and properly tune) a substantially larger supercharger set up. Nitrous oxide fuel shipping can be established-up completely independently from the OEM Ecu and fuel process and consequently helps make nitrous a probable application for German vehicles with stubborn pcs.
4- This is a racer approach… most vehicles look to carry out much better through the wintertime months mainly because the air is cooler, horsepower is elevated, and the tracks though cold, can be well prepared for traction and will warmth up more than enough throughout the night time to permit for traction and to give people the ability to exploit the chilly dense air to submit their greatest moments of the yr. As the temperature will get warmer, traction increases due to the fact the asphalt is warm and sticky, but horsepower is lessened owing to warmer, fewer dense air. Usually racers find that their autos fluctuate in their quarter mile functionality by as significantly as a 50 % a second between their summertime tune and their wintertime tune, specially if you happen to be using a supercharger or turbocharger that compresses (and even further heats) the incoming air.
The option to on-keep track of consistency, racers have found, is to incorporate the use of nitrous oxide (which is summer months pleasant) with forced induction (superchargers and turbochargers) which are wintertime pleasant. In the summer time, the outside the house temperature is substantial, and so the nitrous bottle strain is taken care of at a superior degree previously mentioned 1100 psi. This makes it possible for for a generous nitrous move price beneath the sustained pressure (even devoid of a bottle heater) which provides terrific summer time efficiency for nitrous assisted cars. When in the winter season, the outside the house temperatures drop appreciably, the nitrous in the bottle contracts and the bottle strain drops, subsequently, the nitrous movement price drops and nitrous assisted cars clearly show even worse performance in the wintertime moments.
The full reverse is correct for supercharged autos that create wonderful horsepower in the winter season from compressing interesting dense air, and very poor horsepower in the summer time warmth. When you merge these two electric power adders you get fairly flat and consistent horsepower output yr spherical since the supercharger shines when the nitrous is weak, and the nitrous shines when the supercharger is weak, and so with each other, they give steady power produce yr spherical.
Pre-cautions:
Now we have to consider that nitrous oxide is an oxidizer and so not only does it boost the total of air and fuel combusting in the cylinder, but it also makes a speedier moving flame front owing to the oxidizer homes of the nitrous oxide. This signifies that additional timing retard, good octane fuel, and maybe colder spark plugs will be necessary to operate spray on a supercharged motor vehicle. Also, since of its cooling effect, a 100hp shot on a supercharged Camaro can incredibly quickly place down In excess of 120 rear wheel horsepower of further electric power. This usually means that the ‘out of the box’ jetting of a nitrous package could not be enough on a supercharged auto and you would have to make sure to check and quite possibly boost the gasoline jetting to match the last horsepower determine of your motor vehicle). Very last but not the very least, if you’re running a 500hp supercharged car with an further 120hp of nitrous oxide injection, then you have to make positive that your gasoline shipping (gasoline pump and gas strains) are in a position to stream the whole quantity of fuel necessary to deliver 620hp.
Apps situations:
1- You have a car like mine, a 2005 C230 kompressor that comes with a 230hp restricted Eaton MP45. Eu on the motor vehicle is a Siemens Eu that pretty number of folks know how to tune, and the fuel system employs a return-a lot less setup with an in-tank gasoline force regulator. With this type of setup all sorts of dry nitrous injection are out of the dilemma for the reason that we can neither compensate for gasoline by way of flashing the manufacturing facility Eu, nor can we elevate gas tension for the duration of the nitrous injection because the gas strain regulator is in-accessible….
Recommended kit:
A wet nitrous injection package that injects both fuel and nitrous oxide from the injection nozzle.
Injection locale:
Following the supercharger, just after the intercooler, and into the consumption manifold of the car or truck.
Greatest recommended injection:
25% of the first total energy determine which corresponds to all around a 50 hp shot of nitrous on our illustration.
Expected ultimate horsepower:
60 to 65 wheel horsepower and doable about 130 ft-lbs of further torque!
2- You have a vehicle that has an available fuel pressure regulator, or an Ecu that can be re-flashed for nitrous oxide or a ‘dual tune’ set up. In this case it is advised to use a dry nitrous kit for two factors:
First: Dry kits are safer on supercharged vehicles (as very long as the fuel shipping and delivery by the injectors or elevated fuel strain is suitable) mainly because they hold a lessened likelihood of intake backfires due to the fact the consumption manifold is dry of fuel.
Second: Dry nitrous injection is made up of no gas, and so we never want to fear about gasoline slipping out of suspension from the injected air. This implies that we no for a longer time have to spray the nitrous ideal before the consumption manifold and we now have the alternative to transfer the level of injection much farther back again. Spraying nitrous Prior to the intercooler, proper following the supercharger provides the nitrous stream much more time and extra make contact with with the compressed air coming out of the supercharger which final results in extra cooling and further elevated horsepower.
Advised kit:
A dry nitrous injection package that injects only nitrous oxide from the injection nozzle.
Injection area:
Immediately after the supercharger, prior to or immediately after the intercooler and not essentially correct at the intake manifold of the car or truck.
Utmost recommended injection:
25% of the original full ability determine which corresponds to all around a 50 hp shot of nitrous.
Anticipated ultimate horsepower:
70-75 wheel horsepower and achievable about 130 ft-lbs of added torque!
3- You have a car or truck that has an available gas strain regulator, or an European that can flashed for nitrous oxide or a ‘dual tune’ setup. You also want to make as much horsepower as possible from your nitrous…
In this situation it is advisable to use a dry nitrous package injecting ahead of the supercharger. As we mentioned in our articles on twin charging (combining turbochargers with superchargers for extra functionality), when two ‘chargers’ are chained in collection exactly where a person charger feeds the following, then the two stress ratios of the charger blend mainly because the second charger compresses air that is presently compressed by the first. For case in point two turbochargers set for a 1.5 strain ratio (or 7 psi of enhance), managing in sequential method will consequence in a ultimate strain ratio of 2.25 bar (or 18psi of increase) which is extra than the ‘expected’ 14psi that is the sum of the two raise degrees.
Similarly, injecting nitrous oxide ahead of the supercharger, provides already compressed air. This is true weather we are chatting about nitrous being compressed simply because it has two times the oxygen concentration as regular air or we are speaking about the nitrous cooling and compressing the incoming air. The last amount of money of compression noticed by the supercharger inlet will differ depending on the ratio of incoming air to the sizing of the nitrous shot, and can final result in an raise in boost of concerning .5 to 2.5 psi!
This raise maximize is in addition to the electrical power boost of the nitrous oxide injection and so it can be an further 5 to 25 hp.
Advised kit:
A dry nitrous injection kit that injects only nitrous oxide from the injection nozzle.
Injection place:
Before the supercharger inlet.
Utmost proposed injection:
25% of the authentic overall electric power determine which corresponds to all around a 50 hp shot of nitrous.
Envisioned closing horsepower:
75-100 wheel horsepower and probable about 160 ft-lbs of supplemental torque!
Things to steer clear of:
1- No make any difference wherever you set up the nitrous injection, make confident not to spray nitrous into your MAS air move sensor or your consumption air temperature sensor. These temperature dependent sensors, tell the European to progress the timing in colder disorders. As we described before, nitrous is an oxidizer that raises the pace of journey of the combustion function and thus necessitates managed (if not retarded) ignition timing when compared to a supercharged only set up. Stay clear of spraying on these temperature delicate sensors to reduce accidental timing advance from occurring.
2- Steer clear of spraying a damp package (fuel) prior to your supercharger, as the soaked gas mist will destruction the supercharger rotors and strip their coatings.
3- Make absolutely sure you look at your air gasoline ratio on the nitrous and really don’t adhere to the ‘out of the box’ air to gasoline settings with the kit. For example an extra 2.5 psi in your intake may or may perhaps not be compensated by your inventory European and so relying on how nicely the Ecu reacts you will have to change the gas jetting on the nitrous package.
