FT500 SFI / FT500LITE SFI
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Auxiliary outputs
13.6 Variable camshaft control/Powerglide gearbox
The camshaft control systems that use solenoid valve type NO/NC
such as Honda’s VTEC can be controlled through this output. The user
only needs to inform the solenoid’s turn on RPM.
It is important to notice that the impedance of the variable control
system’s solenoid must respect the auxiliary output limits, which
requires a minimum impedance of 25Ω, or the use of a relay. For valve
timing control systems switched by PWM (such as Toyota’s VVTi), it
is possible to manage it through the Boost Control function, as long
as its characteristics (power, current, etc.) are within the auxiliary
output limits.
This resource can also be used to switch the control solenoid from the
2-speed automatic gear control, Powerglide type. Configure the RPM
to turn on the solenoid responsible for engaging the second gear, only
for drag racing applications.
13.7 Progressive nitrous control
This function drives the solenoids used for the injection of nitrous
oxide in the engine.
As these solenoids have high power (90W) and low impedance
(~1.6Ω), they cannot be connected directly to the auxiliary output.
A solid state relay with appropriate max current and voltage must be
used to power the nitro and fuel solenoids.
Set the output as progressive nitrous output.
In the second option, the fogger only injects nitrous (dry nitrous). Fuel
enrichment is managed by the injection, increasing injection times
based on what has been programmed. The dry nitrous system has
reached better results in tests, giving the engine a more linear power
than the first option. It is important to clarify that in order to use the
dry nitrous system, the fuel injectors must be correctly sized for the
power maximum with the nitrous system operating.
There is a difference in the operation of solenoids that control nitrous
injection and the ones that control fuel injection: nitrous solenoid starts
pulsing after 5%; fuel solenoid only pulses after 20%. Variations may
occur among solenoids from different brands/manufacturers.
When applying the conventional nitrous control, one must start with
a minimum injection time of 20%, but when using dry nitrous, it is
possible to start with 5%, as the injectors – and not the solenoid – will
control fuel injection.
13.8 Boost Control – N75
This auxiliary output configuration allows the driving of a boost
pressure control solenoid. FuelTech recommends using a 3-way N75
solenoid, found in the original 4 and 5-cylinder
VW/Audi Turbo models, which can be directly switched through the
auxiliary output. Such solenoid valve controls the pressure on the top
and bottom parts of the wastegate valve, changing the engine manifold
pressure with which the latter opens.
solenoid valve N75
VW 058-906-283F
Wastegate at the exhaust manifold
This type of valve is used on most cars with adapted turbo, in
competitions, etc.
Example 1: the first way to install a boost valve is connecting it to the
bottom of wastegate valve, similar to the OEM installing in the VW 1.8T.
Select the output signal as activated at 0V and frequency at 20Hz.
This way the boost valve will decrease the pressure under the
wastegate to increase boost pressure.
Wastegate
Free Air
N75
12V
aux output
Boost controller
From boost pipe
wastegate
output
From boost pipe
1
30
86
85
87
Ground
activation
Switched power
12/16V (use fuse)
+12V to load/actuator
Do not
connect
