FT500 SFI / FT500LITE SFI
79
Drag race features
Time based revolution limiter
The RPM control is based on seven RPM and time points that can be
determined as shown in the image above.
This function is frequently used in drag racing cars, because it makes it
easier to control the vehicle, once it allows the traction to be recovered
through an ignition cut ramp.
Disabled
Enabled
Time based advance/retard 1/3
Activates a time based timing
map, starting at the lauch point.
Allows the power control
on specific moments.
[°]
+
-
5
3
2
Degrees
[º]
+2,00
-5,00
3,00
2,50
Time
[s]
-2,00
Time based advance/retard curve
1,25
4
0,55
-8,50
1
0,00
-10,0
Time based advance/retard 2/3
0,00
-2,00
-4,00
-6,00
-8,00
-10,0
-12,0
0,00
1,00
2,00
3,00
4,00
5,00
6,00
7,00
Time based advance/retard 3/3
Time based speed (cut)
This feature is the same as the time based RPM (cut) but instead of
using the engine RPM, it uses the wheel speed or the driveshaft RPM.
Disabled
Enabled
Time based RPM (cut)
performs ognition cuts to
keep engine RPM under
a predefined curve.
Time based RPM (cut) 1/4
RPM progressive range
200
RPM
[
]
RPM
+
-
Time based RPM (cut)
3
1
Revs
[
]
RPM
4700
4500
1,25
0,80
Time
[s]
4500
0,00
2
RPM based ignition map
[%]
+
-
Time based RPM (cut)
3
1
Cut
[%]
70
50
2,70
1,00
Time
[s]
60
0,00
2
Ignition cut curve
It will perform ignition cut to keep the wheel speed/driveshaft RPM
under a predefined curve.
The “Time based RPM (cut) - Limit” is the maximum level, which
means the percentage of ignition events that will be cut to keep the
engine under the rev limiter.
The RPM progression range acts as a smoothing for ignition cut.
Example: rev limiter at 8000rpm, RPM progression range at 200rpm.
From 8000rpm the ignition cut level will gradually increase until it
reaches 90% cut at 8200rpm.
Percentages less than 90% may not keep the engine under the rev
limiter. Bigger RPM progression range tend to stabilize more smoothly
the rev limiter, but allows the RPM to pass the RPM set as rev limiter.
For inductive ignition systems it is recommended to use 90% maximum
level and 200 RPM progression range. For capacitive system, like
MSD, it is recommended to use 100% maximum level and 1 RPM
progression range.
10000
9000
8000
7000
4000
0,00
0,50
1,00
1,50
2,00
3,00
Time based RPM (cut)
2,50
6000
5000
The last screen will show the graph.
Time based RPM (retard)
This feature is very similar to the time base RPM (cut), instead of
cutting the ignition, it will retard the timing, to have a smoother way to
control power and torque to the wheels. The function starts after 2-step.
It is recommended to use this function together with the Time based
RPM (cut) to have a better control of the engine, this way the control
itself will be smoother.
Disabled
Enabled
Time based RPM (retard) 1/4
RPM progression range
200
RPM
Time based RPM (retard)
enables a timing retard
table to keep engine
RPM under a
predefined curve.
Time based
(retard) 2/4
RPM
[
]
RPM
+
-
5
3
2
Revs
[
]
RPM
5500
3700
3,00
2,50
Time
[s]
4500
1,25
4
0,55
3500
1
0,00
3800
RPM based ignition retard curve
Time based
(retard) 3/4
RPM
[°]
+
-
5
3
2
Degress
[º]
+2,0
3,00
2,50
-2,0
Ignition retard curve
4
0,55
-8,5
1
0,00
-10,0
-5,0
1,25
Time
[s]
Time based
(retard) 4/4
RPM
0,0
-2,0
-4,0
-6,0
-8,0
-10,0
-12,0
0,00
1,00
2,00
3,00
4,00
5,00
6,00
7,00
Time based
(retard) 4/4
RPM
0,00
-2,00
-4,00
-6,00
-8,00
-10,0
-12,0
0,00
1,00
2,00
3,00
4,00
5,00
6,00
7,00
Chart curves
OK
Revs
Degrees
1 - Green Speed curve;
2 - Purple speed curve;
3 - Buttons for chart selection that will be in the upper layer;
4 - Check boxes to enable or disable graphic display.;
Time based speed (cut)
This feature is the same as the time based RPM (cut) but instead of
use the engine RPM, it uses the wheel speed (with a wheel speed
sensor or by calculate speed) or the driveshaft RPM. It will perform
ignition cut to keep the wheel speed/driveshaft RPM under a predefined
curve. Generally speaking, this speed/RPM control searches to limit
the wheel speed during the run.
1
3
3
2
4
4
