GReddy Profec - Manual (Page 41)

Boost
Time
Factory
default setting
Boost
Time
Boost
Time
Boost
Time
START
BOOST
Too close
Troubleshooting
Boost Setting Tips
(1) Slowly increase the SET % value and monitor the
new boost pressure until you reach your targeted
boost pressure.
Tip! Program the LAST BOOST to ON, so you can
check the most recent high boost pressure achieved.
(2) Once the ideal SET % value is confirmed to your
ideal target boost pressure, program the START value
below your target boost pressure to improve boost
response.
When the START TYPE is programmed to CONTROL,
the solenoid valve controls the wastegate for the full
range, providing the most control and fastest
response.
** However if the START value is too close to your
target boost pressure, it may have a tendency to
boost-spike. Please be aware that an aggressive START
value can cause dangerous boost-spikes.
(3) Once that is complete, you can program the GAIN
% value to improve boost stability, in cases when
boost drop as RPMs increase. (There may be vehicles
or turbocharger configurations which will not allow
for improvements.)