The 7.3 Powerstroke FFD 205cc Stage 3 Hybrid Injectors will increase horsepower from 100-160hp to the rear wheels with a custom performance chip. In the 99-03 Powerstroke diesel you will have to run a custom programmed chip to make the transition from split shot injection to the new single shot injection. Horsepower increases from 75-135 hp and mileage increase from the more efficient single shot design. These injectors have new nozzles and tungsten coated plungers and barrels. The larger nozzles allow for better control of fuel delivery during the combustion cycle with allows for the added horsepower over the non hybrid injectors. The larger hybrid plunger and barrel in these injectors move more fuel for the same stroke as the stage two injector. These somewhat smaller hybrid injectors are designed to operate with lower High Pressure oil. This is optimal for the 15 degree HPOP or the person with a weak HPOP. These injectors by design give you back oil pressure. These injectors requires only as much HPOP oil as a stock AD. This saves money on a new HPOP system by utilizing the system you already have. Choose the nozzle size for you new injectors. The 30% nozzle is great for low smoke applications with approximately 20hp less than the larger nozzles. The 80% nozzle has slightly less smoke than the 100% but they are identical in power. These come with an outstanding 18 month warranty. Complete set of eight. Core charge required.