AEM 30-6905 Universal Programmable EMS-4 - Manual (Page 141)

Page 141 of 279 EMS-4 Install and Tuning Guide_Rev 1.6
An adjustable regulator allows the static pressure to be raised or lowered via an adjusting screw
that acts on the diaphragm spring. On most adjustable regulators, when the screw is turned in
pressure raises and when it is turned out pressure is reduced. Although we highly recommend
installing a proper fuel delivery system, raising or lowering fuel pressure can compensate for
fuel injectors that may not be properly sized for an application.
Most aftermarket fuel pressure regulators (and OE regulators) use a 1:1 ratio of fuel to boost
pressure for increasing fuel pressure in applications where forced induction is used. This
means that for every psi of boost, fuel pressure is increased one psi. This ensures adequate
fuel delivery under boosted conditions.
Many vehicle manufacturers use a pulse dampener to reduce the pulsations in the fuel rail
caused by the opening and closing of the injectors (a dampener also reduces the noise of the
injectors). In applications where a new fuel system must be installed, a fuel pressure dampener
is integral to ensuring consistent fuel flow to the injectors. AEM fuel rails have a provision for a
pulse dampener. The dampener assembly part numbers are:
Honda PN: 16680-PE7-661 Dampener
Honda PN: 16705-PD1-003 Inner Gasket
Honda PN: 90428-PD6-003 Outer Gasket
AEM PN: 2-602 Fitting for Rail
Before the fuel system is assembled in the vehicle, inspect for debris and damages. Before the
fuel system is checked make sure to have a fire extinguisher near by in case of fire. After the
fuel system is installed you must inspect the integrity of the entire system. Begin by purging the
lines. To do this, run the fuel pump with the hose that connects to the fuel rail placed in a
grounded container. This will eliminate any debris left in hose during its manufacturing process.
Inspect the fuel rail for cleanliness before starting the engine. Make sure that the fuel pressure
is set correctly for your application. Then, reattach all of the hoses and run the fuel pump by
switching the ignition to the “ON” position (DO NOT turn over the engine at this time), and
visually inspect all of the connections for fuel seepage or leaks. If any seepage or leaks are
present in the system, repair them before proceeding.