Injector Upgrades

Larger Injectors for Cummins, Powerstroke, & Duramax



diesel injectors More fuel is more power - it does not get much simpler than that in the world of diesel performance. Increasing the size of your fuel injectors can provide a big boost in performance. Aftermarket injector manufacturers have created injectors for a variety of applications and power levels.


Otherwise Known As:

Injectors, sticks

How It Works:

If you want to make more power, you are going to have to introduce more fuel into the engine. Increasing the flow of your fuel injectors allows you to pump more diesel into the engine with each injection pulse, therefore giving you the potential for more power. Additionally, upgraded injectors can feature enhanced spray patterns & higher injection pressures. Injector upgrades come in 3 common forms. The first is an extrude honed injector, in which an abrasive medium is used to hone the inside of the injector, smoothing and enlarging the holes. The second way to upgrade your injectors is to purchase new injector tips with larger nozzles. These replace the tips on your stock injectors and increase fuel flow. The 3rd form of injector upgrades is to purchase an entirely new injector that features more flow than the stock unit. Injector size & flow lays the foundation for your future modifications and can provide a big boost in performance at any RPM. New injectors are REQUIRED for anyone who wants to take their diesel to the next level.


• Big horsepower & torque gains.
• Good dollar/horsepower ratio.
• Plenty of black smoke.

• Superior spray patterns.


• Lots of black smoke w/out upgraded turbocharger.
• Higher exhaust gas temperatures.
• May require making additional provisions to the fuel system in order to meet the flow requirements of bigger injectors (see pump upgrades).
• Expect to pay a core charge on some sets.

Possible Problems:

• Larger injectors will result in higher exhaust gas temperatures. Driving with high EGT's can cause catastrophic problems. A properly matched turbocharger and intercooler will help keep this under control.
• Blown head gaskets are a possibility if you start raising combustion pressures with bigger injectors. Fuel injector upgrades should be accompanied by a set of head studs.
• Big injectors flow a lot more fuel than stock injectors and your stock fuel pump may or may not be able to provide enough fuel. You may need to upgrade your stock fuel pump and or fuel system.

• Large injectors combined with stock injection pumps will lead to poor fuel atomization.

Est. Gains:

25 - 200+ hp depending on injector size, application, turbocharger, & fuel system.


Power Stroke, Cummins, & Duramax

Additional Info:

Remember that bigger is not always better. Match your injector size to the size of the turbocharger you are running, or the turbocharger you plan on running. A properly matched system will help keep EGT's at a manageable level. Installing larger injectors is a great modification to take your diesel to the next level, but be sure your engine is up to the task before hand (head gaskets, head studs, etc).

Injectors are measured using 3 common methods:
• By flow volume in cc (200cc, 250cc, etc).
• By flow volume in LPM (liters per minute; 30 LPM, 40 LPM).
• By the number of holes x size of the holes (6 x 16 = 6 holes @ .016" each).


Related Topics:

CP3 Pump Upgrades

J Hook Mod

Cummins Fuel Stop Plate

Diesel Intercooler