Holley 550-407, Installation Manual, Page: 46 / 54

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34.0 ADVANCED TUNING
From the HOME MENU, select TUNING, and ADVANCED. There are four areas you can modify; ADV FUEL, CLOSED LOOP, ADV.
LEARN, AND ADV. IDLE. These are reviewed below.
The Advanced Tuning areas typically won’t ever be needed to be changed. However, after getting used to the TERMINATOR™ EFI
system, there may be s
ome fine tuning of various parameters that you’d like to perform.
Figure 119
34.1 Advanced Fuel

Coolant Enrichment: Coolant enrichment is similar to the choke on a carburetor. Adjustments are made as a percentage of the
base map from 100% to 150%. 100% would mean no additional fuel is being added by the Coolant Enrichment, 110% would
mean that an additional 10% of fuel is being added to the base fuel map which will decay back to 100% in relation to actual
engine coolant temperature.

Load Based Acceleration Enrichment: This parameter provides another way of adding fuel when the accelerator is depressed.
It adds fuel depending on how fast the MAP sensor reading changes
(detects a change in engine load). There is typically no need to adjust this parameter except possibly under some extreme
conditions of vehicles that are heavy and under-powered. Adjustment values are in pounds of fuel per hour (pph) and should
initially be adjusted in increments of 5-10 pph

Cranking Fuel: This dictates how much fuel is injected when the engine is cranking and is dependent on coolant temperature.
Changing this value offsets the entire curve at all temperatures. Adjustment values are in pounds of fuel per hour (pph) and
should initially be adjusted in increments of 2-4 pph.

Afterstart Fuel: The afterstart parameter is fuel that is added for a short time immediately after an engine starts. This value
varies depending on engine temperature. Changing this value offsets the entire curve at all temperatures. Adjustments a re
made as a percentage of the base map from 75% to 200%, 100% would mean no additional fuel is being added, 110% would
mean that an additional 10% of fuel is being added to the base fuel map, and 85% would mean that 15% of fuel is being taken
away from the base map. All selections will decay back to 100% over a predetermined amount of time.
Figure 120
34.2 Closed Loop
CLOSED LOOP OPERATION relies on WBO2 sensor readings. The Holley EFI system uses these readings to analyze ‘real time’ running
conditions. The data obtained by the ECU is then used trim fuel flow to achieve the targeted air fuel ratio (AFR).
Choosing CLOSED LOOP from the ADVANCED TUNING menu will allow you to modify four areas of the CLOSED LOOP operation.