FT500 SFI / FT500LITE SFI
32
Fuel injectors
10. Fuel injectors
A FT500 / FT500LITE has 8 outputs to control fuel injectors (blue
wires #1 to #8). Each one of them can control up to 6 injectors with
internal resistance above 10 Ohms (saturated injectors) or up to 4
injectors with internal resistance above 7 Ohms. Using a Peak and
Hold driver, this capacity varies according to the output and the Peak
and Hold current control (2A/0,5A, 4A/1A or 8A/2A).
In situations where more than 8 outputs are needed, the gray or yellow
outputs can be set as injector outputs. In this case, the use of a Peak
and Hold driver for these outputs is mandatory.
Injectors can be triggered in multipoint, semi sequential or sequential
modes.
Examples of 4-cyl engines running high impedance injectors
•
Individual triggering:
each blue output controls a cylinder. This
is the most recommended connection cause is the only one that
allows individual per cylinder fuel compensations, amongst other
functions.
Blue #1
Blue #2
Switched 12V (Injectors relay)
cyl.1 cyl 4
.
cyl 2
.
cyl 3
.
Blue #1
Blue #4
Switched 12V (Injectors relay)
c l.1
y
Blue #2
Blue #3
Blue #1
Switched 12V (Injectors relay)
cyl.1 cyl.2 cyl.3 cyl.4
•
Two injectors per channel: blue output #1
controls injector of
cylinders 1 and 4. Blue output #2 controls injectors of cylinders
2 and 3
•
Four injectors per channel:
use this connection only for
compatibility with previous generation FT ECUs.
Even with each output controlling only one injector it is possible to
change the triggering mode to multipoint (batch fire), semi sequential
(outputs triggered in pairs) or sequential.
11. Ignition
A FT500 / FT500LITE has 8 ignition outputs that can be used
according to the needs of the project, controlling a distributor or a
crank trigger.
Ignition with distributor
When using this ECU with a distributor, the only active ignition output
is gray #1. This wire must trigger an ignition module or a coil with
integrated igniter.
Coil with integrated igniter (smart coil)
They are coils with at least 3 pins and only one spark plug wire
output. This kind of coil (inductive) must be set as “Falling dwell”
in the “Ignition output” menu. In case of selecting the wrong output
type, coil will be damaged.
A - Ground (near coil) / igniter;
B - Signal Ground;
C - 5V signal from sequencer;
D - Switched;
FuelTech SparkPRO-1 with coil without integrated igniter
(dumb coil)
The FuelTech Spark PRO-1 module is an high energy inductive igniter
which has an excellent cost/benefit and can be used with any 2-wire
dumb coil (without internal igniter). Coils with primary least possible
resistance are recommended for maximum SparkPRO-1 potential. The
minimum resistance of the coil primary should be 0.7 ohms, below
this the SparkPRO will be damaged.
Try to place SparkPRO-1 as close as possible to the coil.
Warning about the SparkPRO-1: An excessive
charging time (Dwell) can damage the SparkPRO
and the coil. It is recommended to use a Dwell
map with 6ms at 8V, 4ms at 10V, 3.60ms at 12V
and 3.00ms at 15V and check coils temperature
at the beginning
