Tomei Powered ARMS M7960 - Manual (Page 26)

From wide open throttle to fully closed, even when the throttle is completely closed the mass air can vent
to the atmosphere and the vacuum will suck high flow of air through the AFM. This erroneous readings can
then cause the ECU to over-enrich the burn and/or cause engine failure.
■ The Intake Relief Function (Only with S14 / S15 SR20DET cars)
The S14 / S15 Silvia comes with an Intake Relief Function re-circulation valve setup. When the mass forced
air rises abnormally, this function will allow the high boost pressure to escape back into the intake side.
The valve is set to open at around 0.1~0.4kg/c㎡ at low boost pressure, this means that the rapid
increase in boost is not possible as some of it will vent back into the intake system which causes
power loss. This then hinders the turbos potential.
When boost pressure is increased,
the pressure falls on the
diaphragm and it then opens
the valve to allow the boost
pressure to escape.
Re-Circulation Vent to Atmosphere Valve
Re-circulation
valve
Throttle
Valve
（closed)
Vent to
Atmosphere
Vacuum
(Throttle off)
Vent to Atmosphere
Throttle
Valve (open)
Return Spring Diaphram
Relief
Positive
pressure
Port
EX IN
So to get a high power output engine, it is highly recommended to remove the intake relief function of
the re-circulation valve.
■ Intake Relief Disabling Option
【PROCEDURE】
① To stop the boost pressure from flowing
into the diaphragm chamber, you
block the access port with an epoxy
bond as shown.
② Then drill a small φ1.5mm hole
on the body (as shown in the
illustration) to create an air vent.
26
Throttle
Valve (open) Port
Make a hole/vent
(φ1.5mm)
Seal the hole with some bond