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SMART XEDE A walk-thru and basic tuning guide Rev 1.0 Main XMAP Screen
This is the Main XMAP Screen. Among other things, it tells you if you are “Connected” or “Not Connected” from the XEDE. It also has helpful little shortcut buttons that you can click that will automatically bring up the desired table. You will also use this window to open, close, rename and save XMAP files. Fuel Table
This is the Fuel table (aka Base Fuel table). It is not to be confused with the SMART Fuel table which will be explained later. On the Y-axis is Load. On the X-axis is RPM. At any given operational condition, your engine will be operating in one of these cells. If that cell has a negative number in it, the XEDE will be enleaning the fuel mixture. If it has a positive number in the cell, it will be enriching the fuel mixture. The larger the positive or negative number, the bigger the fueling change will be. In most applications, it will be very rare to have positive numbers in this table. This is because stock ECUs are programmed to run the car every rich as it is. As with all the tables, you will see a little “highlighted box” move around the table as you drive your car. This box indicates where on the table your engine is operating. The more load/boost, the higher up in the table. During cruise conditions, it is normal to be in the 15-20 range. At higher RPM and at full boost, it is normal to see a stock turbo’d EVO to max out in the 50-55 range. EVOs with larger turbos, running high boost with race gas can see as high as 70-80! Tuning Tips 1)
When dialing in this table, it is important to make sure the final map
is reasonably smooth and free of odd spikes and dips. You can check this by looking at the 3D graph just below the
table. If this 3D graph is not open,
you can open it by simply clicking on the bottom left-hand corner of the
window. 2)
To make a chance to the value in a cell (or selection of cells), you can
do a number of things: a) Select the cell(s), hit “Enter” and input
the new desired value. b) Select the cell(s), hit the “<” key to
decrease the current value(s) or “>” key to increase the current value(s) 3)
Don’t be afraid to use the interpolate feature. You can interpolate on either the X or Y
axis. In order to interpolate, select
the portion of the map you wish to interpolate and select Interpolate (Right
mouse click and select “Interpolate”).
Then close which axis you want to interpolate upon and hit enter. Timing Table
This is the Timing table. It is very similar in concept to the Fuel table. Except that it modifies ignition timing instead of Fuel delivery. The bigger the negative number, the more ignition retard the XEDE is inducing. It is very unlikely that you will ever see or need positive numbers in the higher load regions. At most, you may see positive numbers around idle, cruise and partial throttle conditions. Tuning Tips 1) Be very careful when modifying this table. In other words, make very small changes at a
time and carefully monitor the SMART timing table and Knock datalogs every step
of the way. Typos can result in
complete engine failure when dealing with this table. 2) It is also a very good idea to look at the 3D graphical
representation before you test it to make sure there are no bizarre outliners
that could have been caused by a typo.To eliminate a boost spike during spool
up (very common problem), don’t be afraid to reduce the numbers in the
3500-4500RPM region if you need to. SMART Boost Table
This table controls boost pressure by driving the factory boost control solenoid. As with the Fuel and Timing table, the Y-axis is Load and the X-axis is RPM. The values in the table represent Duty Cycle which can vary from 0 to 100%. The higher the value, the higher the boost pressure. You will notice that boost values will be lower at lower RPM than higher RPM. This is because turbochargers will naturally make more boost when they are operating at higher efficiency levels. This is at lower engine speeds. So to prevent an overboost in this RPM band, the numbers are adjusted accordingly. At higher engine speeds, the factory turbo tends to “run out of steam” and taper boost pressures. To help compensate for this boost taper, the numbers in this table are increased as engine speed goes up. You will also notice that duty cycle numbers increase as load goes up. This is because as load goes up, there is less need for boost. This is also to help prevent overboost since the taper in the Y-axis behaves like a self regulating control system. Tuning Tips 3) Leave the bottom two rows zero. This is because there is no reason to keep the factory boost
control solenoid pulsing at low loads.
All this does is heat up the solenoid and the solenoid driving
circuitry. 4) When making adjustments to the supplied baseline map, adjust
the entire column, not just the cell.
This will raise/lower your boost pressure without eliminating the
self-regulating function of the Y-axis tapered table. Of course, keep the bottom two rows zero’d out. 5) To eliminate a boost spike during spool up (very common
problem), don’t be afraid to reduce the numbers in the 3500-4500RPM region if
you need to. 6) Keep mid-RPM boost pressures below 22-23psi on pump gas. With the stock turbo, the boost pressures
will naturally fall of to 17-19psi by 7500rpm.
This is normal. On race gas, you
can safely run 25-26psi in the midrange.
By 7500rpm, boost will still fall off to 17-19psi. SMART Timing Table
The SMART timing table makes realtime adjustments to ignition advance depending on knock noise input from the knock signal buffer. On the Y-axis is knock signal level. On the X-axis is RPM. When knock noise is high (engine is knocking), a negative timing offset will be applied by the XEDE. This is in addition to the timing offset induced by the regular Timing Table. For the most part, the greater the knock signal, the bigger the negative timing offset. The Zero Line” is the line of cells that are zero just below the negative timing values. It is illustrated by the following drawing:
This region signifies the threshold of normal, safe knock signal activity. When the “highlight box” goes above this Zero Line, you can conclude that you engine had at least one knock event and that the SMART timing system intervened and made the necessary timing adjustment. It is not unusual for this to happen during the normal course of driving, from time to time. However, in ideal conditions, our goals is too keep the engine operating in this region (or below it). Tuning Tips 1) DO NOT MODIFY THIS TABLE unless you know exactly what you are
doing. Changing this table, even
slightly, will change the way SMART timing is controlled. An application that may require changes to
this table may be heavily built motors that exhibit a very different (louder)
noise floor. In this case, the Zero
Line may have to be raised or contoured to represent the noise characteristic
of the particular engine. 2) When testing your tuning file, simply highlight the entire
map and drive your car. As the
“highlight box” goes through this table, it will leave a trace. This is the trace that should be in this
“happy zone”. If this trace routinely
goes higher than this “happy zone”, you will need to make the necessary
change(s) in the regular Timing Table (NOT in this SMART Timing Table). To bring a knocking engine back into the
“happy zone” simply make reduce the value in the Timing table. If the number is already an negative value,
make it more negative. Then go back,
select the entire table and watch the highlight box make another trace. SMART Fuel Table
The SMART fuel table makes realtime adjustments to fueling advance based upon the Air/Fuel Ratio input from the Innovate LC-1 wideband o2 sensor. On the Y-axis is 02 sensor signal voltage (smaller number is richer, bigger number is leaner). On the X-axis is RPM. When o2 sensor voltage is higher than desired (AFR is lean), the XEDE will induce a real-time fuel enrichment. When richer than desired, the XEDE will induce a real-time fuel enleanment. The “Zero Line” is the line of cells that are, well, zero. It is illustrated by the following drawing:
This region signifies the normal AFR plot during a full throttle, full boost, dyno-style single gear pull.. When the “highlight box” goes above this Zero Line or “Happy Zone”, you can conclude that you engine is running leaner than desired and the SMART fuel system intervened and made a quick fuel enrichment. When it goes below this “Happy Zone”, it can be concluded that the engine is running richer than desired and that the XEDE induced a fuel enleanment. You will notice that the highlighted box stays in the bottom row during cruise and lower load conditions. This means that the SMART fuel system is inactive during this time. It will only become active as dictated by the Fuel Threshold Map (more on that later). Tuning Tips 1) DO NOT MODIFY THIS TABLE unless you know exactly what you are
doing. If you have different AFR values
that you wish to target, you can adjust this table according by offsetting
entire columns in the positive or negative direction. Offsetting them in the negative direction will make the zero
point/Happy zone leaner. Offsetting
them in the positive direction will make them richer. Be careful not to set them too lean or else the term “happy zone”
will be a misnomer. 2) When testing your tuning file, simply highlight the entire
map and drive your car under full throttle.
As the “highlight box” goes through this table, it will leave a
trace. This is the trace that should be
in this “happy zone”. If this trace
routinely goes higher or lower than this “happy zone”, you will need to make
the necessary change(s) in the regular Fuel Table (NOT in this SMART Fuel
Table). To bring a too lean or too rich
running engine back into the “happy zone” simply increase or decrease the
relevant cell values in the Fuel table.
Then go back, select the entire table and watch the highlight box make
another trace. 3) You may notice that race gas maps have a SMART fuel table
that looks a bit different. That is,
the “happy zone” is a bit leaner than it was on a pump gas map. This is because race gas allows you to
safely target a leaner AFR. Fuel Threshold Table
This is the Fuel Threshold table. We actually wanted to call it the “SMART Fuel Threshold Switch Table” but the name was too long. But that name gives you an idea of what it does. Simply put, it decides when the SMART fuel system is active and inactive. Unlike SMART Timing which is always active, the SMART fuel table only kicks on under high load. In this case, the SMART fuel system turns on above a Load of 40. We don’t want the SMART fuel system to run at lower engine loads (idle, cruise, light load) because our desired AFR targets in the SMART fuel table are no longer appropriate.
Tuning Tips 1) For the most part, there is no reason to ever mess with this
table unless you want to disable the SMART fuel system. You can do this by inputting “-100” in all
the cells. You would do this for the
following reasons. -
Your wideband o2 sensor has
failed or has yet to be installed. -
You are trying to dial in your
regular Fuel table without the influence of any other real-time changes.
This is the Launch Control table. When the clutch switch is fed into the XEDE (see http://www.vishnutuning.com/Smart/launch_control.htm for wiring instructions), you can use this feature. The Y-axis represents Clutch position (100=clutch in, 0=clutch out) and the X-axis is RPM. As per the above example the XEDE will induce a 5800rpm when the clutch is depressed. To raise the Launch RPM limit to 6300rpm, simply modify the table to look like:
The launch control table also induces a “No Lift Shift” feature. This allows you to keep your throttle fully planted open between shifts since the simple act of pushing the clutch in induces a fuel cut. Without having to lift between shifts, you will find that your car will maintain 10-15psi of boost between shifts and shave up to 0.5 seconds off your ¼ mile ET.
Tuning/Driving Tips 1) Remember, that for the time being at least, this table
represents the secondary fuel cut once the clutch is pressed in. If you lower the RPM point to much, it will
interfere with your normal driving style since the fuel cut will be induced
during clutch-in rev matching. Also,
when practicing no-lift shifts, make sure that you go high enough into the revs
so that you actually active the fuel cut once the clutch is pushed in. For example, if your launch RPM is set at
6000rpm, no lift shifting at 5000 will not work! 2) That clutch switch is VERY sensitive. Simply resting your foot lightly on the
clutch pedal may activate it by accident. 3) To disable Launch Control/NLS, you can either disconnect the clutch switch wire from the XEDE or put Zeros in the entire table. Methanol Control
More info coming soon…. Lean-Run Protect
This is the Lean-Run Protection table. It is used to safe your engine from a sudden lean-run conditions. This could be caused by a fuel pump/injector failure, or methanol/water jet clogging or tank depletion (not very uncommon, unfortunately). On the Y-axis is o2 sensor voltage. On the X-axis is RPM. The value in the cell represents system fueling offset. With 0 in a cell, there is no fueling offset. With -100% in a cell, a fuel cut is induced. To active a fuel cut when AFR goes leaner than 13.4:1, simply adjust the table to look like:
To figure out what Y-axis number equals what AFR, you can
refer to the following table: Y-Axis
AFR
Note: This protection is only active when the engine is operating above the load dictated by the Fuel Threshold Table. If that load point is not reached, the lean protect will not work. Also, at this time, Lean-Run Protect will not work with launch control. This is because the act of No Lift Shifting induces all the signs of high boost lean run without actually running lean. Until we add the necessary conditional logic, pick the feature you want to run and disable the other. Tuning Tips 1) Don’t make the Lean-run protection AFR too rich or this table
may false trigger and induce an unnecessary fuel cut. A good AFR range to have it triggered is between 13.4 and
14.5:1. This will work perfectly with
methanol injection systems because, once they run out of methanol, the car ends
up running an AFR of 15-16:1!! 2) To disable this table, simply put Zeros in all the cells. Troubleshooting Problem 1: Not all the tables/maps showed up when I opened the file (either from the XEDE or from your HD) Solution: This is usually by your desktop area being too small and one or more of the tables are off the screen. To get around this problem, go to the “Maps” menu and select “Tile Maps” or simply hit “F10”. If the desired table still isn’t there, close a few of the undesired tables and hit F10 again. Each time you hit F10, all the tables/maps get re-tiled on your desktop screen. Eventually, the desired map will be exposed. The more tables any given map has, the more likely you will run into this problem.
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