Fuel Maps
The Nemesis
2.5 features 3 fuel control maps: the (base) fuel
map, fuel anti-lag trim and fuel auxiliary trim. The
ECU operates as a 'speed density' system using
onboard 3BAR map sensor, with the inputs to all fuel,
spark and AFR target maps being rpm and load. All
fuel and spark maps are 32 x 32 point with user
programmable point spacing. All maps can be tuned in
real time or offline.
The basic fuel quantity is calculated from the fuel map. Resolution is 0.004 ms (4 us). This map is always the base point for all fuel calculations; there are no wide open throttle or closed throttle maps.
When anti-lag is used, the fuel amount delivered can be trimmed using the fuel anti-lag trim map. Resolution is 0.08 ms, for a total trim of +-10 ms. Anti-lag trim can be requested through a switch to power or ground, connected to any of the 6 auxiliary inputs. Alternatively, anti-lag trim could be requested through an auxiliary input by a connection to an anti-lag air valve.
When auxiliary trim is used, the fuel amount delivered can be trimmed using the fuel auxiliary trim map. Resolution is the same as for anti-lag trim, and auxiliary trim is commonly triggered through an 'alternate fuel' or 'nos' switch to power or ground, connected to any of the 6 auxiliary inputs.
The basic fuel quantity is calculated from the fuel map. Resolution is 0.004 ms (4 us). This map is always the base point for all fuel calculations; there are no wide open throttle or closed throttle maps.
When anti-lag is used, the fuel amount delivered can be trimmed using the fuel anti-lag trim map. Resolution is 0.08 ms, for a total trim of +-10 ms. Anti-lag trim can be requested through a switch to power or ground, connected to any of the 6 auxiliary inputs. Alternatively, anti-lag trim could be requested through an auxiliary input by a connection to an anti-lag air valve.
When auxiliary trim is used, the fuel amount delivered can be trimmed using the fuel auxiliary trim map. Resolution is the same as for anti-lag trim, and auxiliary trim is commonly triggered through an 'alternate fuel' or 'nos' switch to power or ground, connected to any of the 6 auxiliary inputs.
Fuel Map - Actual shot of Tuning Interface |
Floating 32 x 32 Fuel Map |
Spark Maps
The basic
ignition timing is calculated from the spark map.
Resolution is 1 degree. This map is always the base
point for all timing calculations; there are no wide
open throttle or closed throttle maps.
The spark anti-lag trim map and spark auxiliary trim map function and are triggered in a similar way to the fuel map equivalents.
The spark anti-lag trim map and spark auxiliary trim map function and are triggered in a similar way to the fuel map equivalents.
Control Maps
The Nemesis
2.5 has 24 control maps, most of which are
compensation maps that allow for smooth starting and
driving and excellent AFR consistency. The following
table lists all 24 control maps and their functions.
PWM Maps
PWM maps 1 -
8 are 16 fixed point user programmable duty cycle
curves. The input can be selected from a large set of
operating variables such as coolant temp, rpm or AFR.
Resolution is 0.4% duty cycle. Common uses for the 2D
PWM maps are boost control valve, external AFR
display control, variable speed thermofan and ETC
(electronic throttle control) virtual idle speed
control.
PWM maps 9 - 11 are 24 x 24 fixed point user programmable duty cycle maps. The input for each axis can be selected in the same way as for the 2D PWM maps. Resolution is 0.4% duty cycle. PWM Map 9 is only used closed loop variable cam timing. PWM map 10 and 11 can be configured for other options such as Open Loop Variable Cam Control, electronic EGR (exhaust gas recirculation) and open loop boost control.
PWM maps are tied to the hardware PWM outputs by selection in the output configuration window.
PWM maps 9 - 11 are 24 x 24 fixed point user programmable duty cycle maps. The input for each axis can be selected in the same way as for the 2D PWM maps. Resolution is 0.4% duty cycle. PWM Map 9 is only used closed loop variable cam timing. PWM map 10 and 11 can be configured for other options such as Open Loop Variable Cam Control, electronic EGR (exhaust gas recirculation) and open loop boost control.
PWM maps are tied to the hardware PWM outputs by selection in the output configuration window.
Closed Loop Variable Cam
Full closed
loop control of Variable Cam on today’s cars (Subaru
AVCS, Mitsubishi MIVEC, Toyota VVTi, Honda I-VTEC.)
3D adjustable Map in Crank degrees based on load and
rpm.
AFR Target Map
The AFR
target map has the same rpm and load axes spread as
the fuel and spark maps. The AFR target map sets the
desired AFR for the wide band closed loop option, and
for the auto-tune option. The resolution for this map
is 0.1 AFR. The wide band closed loop is enabled by
selecting the AFR target table as the source for
either of the closed loop fuelling modules.
Wide band closed loop has advanced PID control that delivers a smoother action than the common jump-ramp method used with narrow band sensors.
Wide band closed loop has advanced PID control that delivers a smoother action than the common jump-ramp method used with narrow band sensors.
Output Options
PWM 1 - 14
and 16 are multi-configurable, with two different PWM
frequencies, or the option of hard switching. Output
options on all channels include turbo timer, user
defined switching, AC and check engine lamp. Channel
restricted output options include boost control,
variable cam control and PWM idle speed
control.
User defined switching is a useful option where an output can be programmed to switch on (or off) depending on the operating conditions. For example, a boost alarm could be set by defining a user switch as 'boost > 15 psi'. 'And' logic can also be used. For example, the high boost solenoid of an after-market boost control valve could be switched on by defining a user switch as 'coolant temp > 50 C AND air temp < 50 C'. This would protect the engine from high boost during warm up and at excessive inlet air temperatures.
*Configurable 2D and 3D outputs
*password encrypted
Outputs are normally Locked by Dealer and will require Password Unlock code to access. This is to prevent accidental changes to prewired outputs of the ECU.
User defined switching is a useful option where an output can be programmed to switch on (or off) depending on the operating conditions. For example, a boost alarm could be set by defining a user switch as 'boost > 15 psi'. 'And' logic can also be used. For example, the high boost solenoid of an after-market boost control valve could be switched on by defining a user switch as 'coolant temp > 50 C AND air temp < 50 C'. This would protect the engine from high boost during warm up and at excessive inlet air temperatures.
*Configurable 2D and 3D outputs
*password encrypted
Outputs are normally Locked by Dealer and will require Password Unlock code to access. This is to prevent accidental changes to prewired outputs of the ECU.
Ignition Control
Sequential
ignition gives a constant coil charge even at extreme
engine speeds. The Nemesis 2 has advanced ignition
control which retards the timing before fuel cutting
for a smoother deceleration fuel cut, as well as
progressive advance angle changes which deliver
superior driving characteristics.
The launch control ignition cut option allows a user set 'fire - miss - fire' pattern. To protect against detonation damage due to bad fuel or incorrectly set timing, the knock limit function can trigger the Nemesis 2 to revert to a conservatively set backup spark map. The Nemesis 2 does not support any Rotary engine applications at this time.
The launch control ignition cut option allows a user set 'fire - miss - fire' pattern. To protect against detonation damage due to bad fuel or incorrectly set timing, the knock limit function can trigger the Nemesis 2 to revert to a conservatively set backup spark map. The Nemesis 2 does not support any Rotary engine applications at this time.
Input Control
Auxiliary
input 1 - 3 analog inputs are commonly used for
external map sensor, drive by wire pedal position or
barometer (use a GM 1 bar map sensor). Auxiliary
input 1 - 4 are digital only, options include clutch
pedal for launch control, AC switch for AC request or
dash mounted alternate fuel switch.
The state of all auxiliary inputs can be used to trigger a user defined switch. For example, an intercooler water spray pump could be configured with a master switch connected to aux 1. If the switch was to ground, then the pump could be set by a user switch 'aux 1 < 2.5 V AND boost > 2 psi'. The pump would only run if the master switch was on and the engine making boost.
The state of all auxiliary inputs can be used to trigger a user defined switch. For example, an intercooler water spray pump could be configured with a master switch connected to aux 1. If the switch was to ground, then the pump could be set by a user switch 'aux 1 < 2.5 V AND boost > 2 psi'. The pump would only run if the master switch was on and the engine making boost.
Fuel Control
Sequential
injection delivers superior fuelling by reducing the
entrainment of fuel at the ports and valves during
the inlet cycle. This will generally give fuel
economy improvements and a reduction in emissions,
especially at low rpm. By injecting fuel
once-per-cycle, the Nemesis 2 can effectively control
injectors up to 1000 cc/min flow.
Where no cam sync signal is available, the Nemesis 2 can fire injectors in batch fire mode. With an effective strategy to deal with manifold and port wetting, the Nemesis 2 can also run throttle body injection engines without large AFR errors.
All unused injector outputs can be used for simple switching, as for the aux (PWM) outputs. Injectors 2 - 5 can be used as PWM outputs when not required for batch fire injection (when sequential injection is used, the appropriate injector outputs are injection only).
Fuel Injection setup strategies (missing img)
Staged injection(optional) is seamless with only a single setting required. The Nemesis 2 will run the main bank of injectors up to their maximum flow, and then will supply the undeliverable amount through the staged injectors. Staged injection is batch fire only, but can be used to supplement both sequential or batch fire main injection. The launch control injection cut option allows a user set 'inject - miss - inject' pattern. The soft fuel cut also operates this way, with the hard fuel cut completely cutting the fuel flow.
The Nemesis 2.5 has both narrow band and wide band closed loop fuelling options. Support is included for individual closed loop control on twin banks, with narrow band sensors only. The wide band closed loop option requires our NTK L2H2 to be fitted, and allows for a far superior PID fuel control algorithm to be used. The AFR will no longer oscillate around the target AFR, rather the AFR will settle very close to the target within seconds of being disturbed
Narrow and Wideband O2 Air/Fuel Long and Short Term Control (missing img)
Where no cam sync signal is available, the Nemesis 2 can fire injectors in batch fire mode. With an effective strategy to deal with manifold and port wetting, the Nemesis 2 can also run throttle body injection engines without large AFR errors.
All unused injector outputs can be used for simple switching, as for the aux (PWM) outputs. Injectors 2 - 5 can be used as PWM outputs when not required for batch fire injection (when sequential injection is used, the appropriate injector outputs are injection only).
Fuel Injection setup strategies (missing img)
Staged injection(optional) is seamless with only a single setting required. The Nemesis 2 will run the main bank of injectors up to their maximum flow, and then will supply the undeliverable amount through the staged injectors. Staged injection is batch fire only, but can be used to supplement both sequential or batch fire main injection. The launch control injection cut option allows a user set 'inject - miss - inject' pattern. The soft fuel cut also operates this way, with the hard fuel cut completely cutting the fuel flow.
The Nemesis 2.5 has both narrow band and wide band closed loop fuelling options. Support is included for individual closed loop control on twin banks, with narrow band sensors only. The wide band closed loop option requires our NTK L2H2 to be fitted, and allows for a far superior PID fuel control algorithm to be used. The AFR will no longer oscillate around the target AFR, rather the AFR will settle very close to the target within seconds of being disturbed
Narrow and Wideband O2 Air/Fuel Long and Short Term Control (missing img)
Advanced Features
Nemesis 2.5
has many advanced features to make tuning easier and
ECU performance just like stock. On the programming
software end, all 3D maps can be rotated in both axes
for a better viewing angle, and the colors of the map
can be altered to suit the user. A change injector
flow utility allows for a global change of the fuel
map based on the old and new injector flows. When
viewing the 2D knock threshold table, the current
knocking detected by the ECU is superimposed on the
curve, allowing the user to define the knocking
threshold just above the background noise. If the
knock background noise becomes excessive at high
rpm (it often does), then the feedback will show
this and the threshold can be set above this noise at
only the rpm where it occurs.
The Nemesis 2.5 ECU has both short and long term trim for the narrow band closed loop system. If the ECU must consistently add or subtract more than 8% fuel from the base value in order to reach 14.7 AFR, then the long term trim table can 'learn' this tendency and correct for it for the duration of the drive cycle.
The Nemesis 2.5 also has factory like features such as flashing check engine light diagnostics for conditions such as lean under load, excessive knock and barometer out of range. A flashing check engine light can alert the user to a potential problem before it causes driving problems or engine damage.
All standard (non drive-by-wire) Nemesis ECUs are identical, and can be loaded with any map for any supported application. A dealer does not have to keep multiple units on the shelf for each different potential customer.
The Nemesis 2.5 ECU has both short and long term trim for the narrow band closed loop system. If the ECU must consistently add or subtract more than 8% fuel from the base value in order to reach 14.7 AFR, then the long term trim table can 'learn' this tendency and correct for it for the duration of the drive cycle.
The Nemesis 2.5 also has factory like features such as flashing check engine light diagnostics for conditions such as lean under load, excessive knock and barometer out of range. A flashing check engine light can alert the user to a potential problem before it causes driving problems or engine damage.
All standard (non drive-by-wire) Nemesis ECUs are identical, and can be loaded with any map for any supported application. A dealer does not have to keep multiple units on the shelf for each different potential customer.
32x32 Configurable Spread for both RPM and Load
All 3D fuel
and timing tables are configurable by user for both
the desired boost and rpm requirements of their
application.
Data Logging
Data logging
is standard on the Nemesis 2.5. The user can log
using a PC, or by using the log buffer memory in the
ECU. After an ECU buffered session, the log can be
uploaded to a PC, analysed and saved to disk using MS
Excel. 8 selectable parameters can be logged at up to
6 times per second for 10 minutes, 3 times per second
for 20 mins, etc. The buffered data logger starts
automatically when the engine starts running.
The PC buffered logger can sample 16 fixed parameters at up to 15 times per second (PC speed dependent). A maximum of 30k of data can be buffered in the PC, then analysed and saved to disk using MS Excel. The fixed parameters are coolant temp, AFR, rpm, TPS, boost, vehicle speed, knock, air temp, fuel duty, knock retard degrees, boost valve output, rpm load point, vacuum/boost load point, fuel amount, vacuum and ignition timing.
The PC buffered logger can sample 16 fixed parameters at up to 15 times per second (PC speed dependent). A maximum of 30k of data can be buffered in the PC, then analysed and saved to disk using MS Excel. The fixed parameters are coolant temp, AFR, rpm, TPS, boost, vehicle speed, knock, air temp, fuel duty, knock retard degrees, boost valve output, rpm load point, vacuum/boost load point, fuel amount, vacuum and ignition timing.
File Transfers
ECU files can
be downloaded to and uploaded from the Nemesis. Files
are stored in the ECU or in the PC. To protect the
intellectual property of a dealer or tuner, sections
of a file (such as the spark map) can be hidden from
view by selectively setting the ECU password keys.
Password Encryption to lock out Fuel, timing and other maps (missing img)
Password Encryption to lock out Fuel, timing and other maps (missing img)