Direct Port FAQ
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Direct Port FAQ
Direct port Nitrous Systems Facts List
The purpose of this technical write up is to explain the benefits and disadvantages of a direct port nitrous system. After reading this article you should have a better understanding of how a direct port system fuctions as well.
What Is a Direct port Nitrous System-
Direct port Nitrous Systems places a nozzle into each individual intake runner. These systems can be used on any application such as motor cycles, boats, cars, etc.
Pros of a Direct port System-
Individual Cylinder tuning- Since a direct port places a nozzle into each intake runner you will have the ability to individually tune a cylinder that may be running richer or leaner than the others. You can richen or lean each cylinder by simply changing out the fuel jet in the nozzle. You have the ability of having a more precise tune up!
Better Flow Distribution- Since a direct port places a nozzle in each individual intake runner you have the ability of spraying higher HP shots and keeping an even flow to each cylinder.
Cons of a Direct port System-
Cost- Since a direct port system consists of more components there is an added cost for the system.
Labor- Installing a direct port system is much more labor intensive. It requires removing the intake manifold, drilling and taping the intake manifold and plumbing the nitrous system onto the manifold.
Tuning- Since a direct port places a nozzle into each intake runner you have more jets to swap in the event of a jet change.
The Difference between Wet & Dry Direct port Systems-
Wet- A wet direct port system injects both Nitrous and Fuel through the nozzle into each intake runner. You will adjust your air fuel to each runner by tuning with the fuel jets.
Dry- A dry direct port system injects nitrous only into each intake runner through the nozzle. The extra needed fuel is added separately through the fuel injectors. With a dry direct port system you can only adjust each individual cylinders air fuel if you have after market tuning software that will able you to change the fuel flow to each injector.
What is Right for Your Needs.-
Every application is different. On some applications you may not have any other choice than a direct port system. Intake designs and flow characteristics will play a huge roll in what type of system best fits your applications needs.
Due to the high fuel pressure on EFI applications I do not recommend using a direct port system with the factory flowing fuel pressure if there are other reliable choices available. With the high flowing fuel pressure anything under a 200 hp shot will require a very small orifice fuel jet. This internal orifice of the jet becomes so small that contaminates could clog the fuel jet. On EFI applications using a direct port nitrous system with smaller HP ratings I suggest using a dedicated fuel system set at 10 psi to supply the nitrous system. This will increase the internal orifice size of the fuel jet and make tuning much easier.
I hope that after reading this most of your answers in regards to direct port nitrous systems have been answered.
The purpose of this technical write up is to explain the benefits and disadvantages of a direct port nitrous system. After reading this article you should have a better understanding of how a direct port system fuctions as well.
What Is a Direct port Nitrous System-
Direct port Nitrous Systems places a nozzle into each individual intake runner. These systems can be used on any application such as motor cycles, boats, cars, etc.
Pros of a Direct port System-
Individual Cylinder tuning- Since a direct port places a nozzle into each intake runner you will have the ability to individually tune a cylinder that may be running richer or leaner than the others. You can richen or lean each cylinder by simply changing out the fuel jet in the nozzle. You have the ability of having a more precise tune up!
Better Flow Distribution- Since a direct port places a nozzle in each individual intake runner you have the ability of spraying higher HP shots and keeping an even flow to each cylinder.
Cons of a Direct port System-
Cost- Since a direct port system consists of more components there is an added cost for the system.
Labor- Installing a direct port system is much more labor intensive. It requires removing the intake manifold, drilling and taping the intake manifold and plumbing the nitrous system onto the manifold.
Tuning- Since a direct port places a nozzle into each intake runner you have more jets to swap in the event of a jet change.
The Difference between Wet & Dry Direct port Systems-
Wet- A wet direct port system injects both Nitrous and Fuel through the nozzle into each intake runner. You will adjust your air fuel to each runner by tuning with the fuel jets.
Dry- A dry direct port system injects nitrous only into each intake runner through the nozzle. The extra needed fuel is added separately through the fuel injectors. With a dry direct port system you can only adjust each individual cylinders air fuel if you have after market tuning software that will able you to change the fuel flow to each injector.
What is Right for Your Needs.-
Every application is different. On some applications you may not have any other choice than a direct port system. Intake designs and flow characteristics will play a huge roll in what type of system best fits your applications needs.
Due to the high fuel pressure on EFI applications I do not recommend using a direct port system with the factory flowing fuel pressure if there are other reliable choices available. With the high flowing fuel pressure anything under a 200 hp shot will require a very small orifice fuel jet. This internal orifice of the jet becomes so small that contaminates could clog the fuel jet. On EFI applications using a direct port nitrous system with smaller HP ratings I suggest using a dedicated fuel system set at 10 psi to supply the nitrous system. This will increase the internal orifice size of the fuel jet and make tuning much easier.
I hope that after reading this most of your answers in regards to direct port nitrous systems have been answered.
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