Power Driven 4BT 025 Delivery Valves for Cummins

4BT 025 Delivery Valves

Power Driven Diesel 4BT Cummins Engine 025 Delivery Valves are for those who want a little more power than the 055s can produce, but with less smoke/heat than the 7 mm’s. Capable of flowing an additional 65 cc over the stock pump, these delivery valves have the potential to produce 100 hp over stock while retaining manageable EGTs.

What is a Delivery Valve?

When it comes to the fuel side of things, 3 aspects of P-pumped trucks determine how much power can be produced: the injection pump itself, the fuel injectors, and the delivery valves. In the P7100 pump, the delivery valves are essentially “check valves” installed between the pump and the injector, controlling the overall amount of fuel that goes into the injector before it is sprayed into the piston bowl. Consequently, a larger delivery valve allows a longer duration of the injection event, thereby increasing potential power. There is a tradeoff, however; as a larger delivery valve increases duration, it results in a longer, less efficient injection event. While the increase in flow does produce more power, it does so at the expense of heat and smoke. A smaller delivery valve paired with the same injector will have a shorter injection event. This results in a clean and concise burn, which will make less power but will ultimately drop EGTs and be more efficient. As a final note, stock/small delivery valves become restrictions around 3000 rpm, where a larger delivery valve will maintain peak flow throughout the rpm range. This is a must for those seeking high-rpm power.

Big DVs/Small Injectors vs. Small DVs/Big Injectors

Both delivery valves and injectors are used to increase power output via increasing total fuel flow. A small delivery valve/large injector combination for a given power level will produce clean and efficient power. A large delivery valve/small injector combination can produce the same power as the small DV/large injector combo but with more heat and smoke. It seems like a no-brainer, so why do so many choose to go with the latter?

The answer is in the cost. Delivery valves are much cheaper than injectors, and for those looking to stay within a given budget, the larger injectors may not fit the bill. Some of our customers choose to keep the stock delivery valves and only upgrade to larger injectors in order to create the most efficient power. However, a large advantage of any delivery valve upgrade is the significant increase in throttle response that is often not attainable by injectors alone.