Ok,
I decided to make a little write up of it so sort out a few things
I will use Colors for the SMT6 only and it will point to the corresponding M20 Wire as it should be buy as it´s in the bentley or other information ( I didn´t want to say anything specific here as wire numbers can change over the years )
Installations details and directions follow the wiring information
First : There are 2 diffrent basic ways of running a SMT6 on a M20 engine
#1 : Original way by Perfect Power
This version takes the ignition signal from the timing wheel or pre ´87 from the gearbox signal, problem sometimes is that the signal is weak and thus the SMT6 looses it´s ignition signal from time to time,
SMT6 wires ----> Usage
POWER AND GROUND
RED >> switched power source (power to SMT6)
BLACK >> solid ground (ground to SMT6)
AFM Signal
wire must be cut to be able to change anything
cut wire end from afm connects to BLUE of the SMT6(Air metering input)
VIOLET(air metering output) from SMT6 connects to the cut end on the ecu,
Load signal
The load signal on the M20 is the AFM signal
connect the AFM signal to the BROWN (It´s now connected to BLUE and BROWN )
Ignition
Tap into wire first with the YELLOW(Ign in) then after have set the ignition information, you should start the engine and if the revs are accurate and you can drive the car this way, using the ignition to pickup RPM for the SMT6, you can cut the signal open,
Signal end goes into YELLOW of SMT6
Output from SMT6 is PINK and attaches again to the cut end of the signal wire going to the ECU, if SMT6 is correctly setup you should be able to start the car without any problems and change the ignition
Global settings information for Version 1
CYL : 6
Teet per turn : 60
Teeth per firing : 20
Mode : 1
System config
Positive input : ON
Positive output pol : ON
low level input : ON
#2 : Updated version by Perfect Power
This version takes the ignition signal from the coil signal wich is a stable square wave signal and is very strong and easily tunable
SMT6 wires ----> ECU plug number and description
POWER AND GROUND
RED >> switched power source (power to SMT6)
BLACK >> solid ground (ground to SMT6)
AFM Signal
wire must be cut to be able to change anything
cut wire end from afm connects to BLUE of the SMT6(Air metering input)
VIOLET(air metering output) from SMT6 connects to the cut end on the ecu,
Load signal
The load signal on the M20 is the AFM signal
connect the AFM signal to the BROWN (It´s now connected to BLUE and BROWN )
Ignition
Wire is the coil signal from the ecu to coil
First tap into the wire and connect it to the YELLOW wire, you should see the revs
on the software
Cut the wire and attach the end from the ecu to the YELLOW wire also connect one BLACK/BLUE wire to the YELLOW wire (this is to juice up the singal a bit for the SMT6 to be able to send out a strong signal again)
Attach the wire from the coil to the WHITE wire,
you now have control over the ignition
Global settings information for Version 2
CYL : 6
Teet per turn : 3
Teeth per firing : 1
Mode : 10
System config
Positive input : ON
Positive output pol : ON
low level input : OFF
Interlace : OFF
Installation instructions and guidelines
I personally reccomend soldering all final connections for best durability and least distortion of the signals also use shrink tubes over the soldering
Ignition installation
First you tap into the signal wire to make sure that it´s usable,
after you have come to the conclusion that is will work fine then you can cut it,
Load signal :
The E30 TPS is a switch not a variable resistance unit like later models have, altough you can retrofit one it´s not available to everybody to do so,
Thus the SMT6 uses the AFM signal as a load signal, tuning will not be as easy as with a variable one but will work nonetheless
Fuel Zero calibration :
This is used primarily when you have installed a diffrent metering device that still uses the same princible, like a maf swap,
If you swap in a MAF you can still use the zero cal. set to 0 but the map will be loaded with more numbers and may seem confusing, that´s why using the zero cal. to move the "0" in the map around to maintain a clean map helps
Note on Motronic AFM readings, it has come to my attention that the ecu reads the afm signal difrently depending on TPS switch, there is a diffrence between AFM reading when the TPS is at Partial and WOT, also idle setting,,
One trick we used first on stefáns car was to short the TPS to show the ECU idle at all times that made fuel tuning a cake, what changes it made to ignition is not known, so we do not reccomend that trick,,
General tuning
Not everybody agrees on what is the best AFR , but it seems to be close to 12.8-12.9
aiming for that AFR is a good goal,
side note on that issue : The SMT6 is designed to use a BOSCH semi wide O2 sensor and not a standard narrow sensor,,
But you can still use the voltage readings from a narrow band to lean on when doing fuel tuning, as 12.8 is about 0.88V aiming for that voltage reading from the O2 during WOT would be ideal,,
Ignition tuning,
Retard is lower then 0
Advance is greater the 0
The 0´s don´t mean that the spark comes at TDC but it comes at the pre determined time from the ECU maps, thus -1 retards 1° from stock and so on,
Hope this helps,
Please ask your questions here so that other may benfit from them and the answeres as well,,
I decided to make a little write up of it so sort out a few things
I will use Colors for the SMT6 only and it will point to the corresponding M20 Wire as it should be buy as it´s in the bentley or other information ( I didn´t want to say anything specific here as wire numbers can change over the years )
Installations details and directions follow the wiring information
First : There are 2 diffrent basic ways of running a SMT6 on a M20 engine
#1 : Original way by Perfect Power
This version takes the ignition signal from the timing wheel or pre ´87 from the gearbox signal, problem sometimes is that the signal is weak and thus the SMT6 looses it´s ignition signal from time to time,
SMT6 wires ----> Usage
POWER AND GROUND
RED >> switched power source (power to SMT6)
BLACK >> solid ground (ground to SMT6)
AFM Signal
wire must be cut to be able to change anything
cut wire end from afm connects to BLUE of the SMT6(Air metering input)
VIOLET(air metering output) from SMT6 connects to the cut end on the ecu,
Load signal
The load signal on the M20 is the AFM signal
connect the AFM signal to the BROWN (It´s now connected to BLUE and BROWN )
Ignition
Tap into wire first with the YELLOW(Ign in) then after have set the ignition information, you should start the engine and if the revs are accurate and you can drive the car this way, using the ignition to pickup RPM for the SMT6, you can cut the signal open,
Signal end goes into YELLOW of SMT6
Output from SMT6 is PINK and attaches again to the cut end of the signal wire going to the ECU, if SMT6 is correctly setup you should be able to start the car without any problems and change the ignition
Global settings information for Version 1
CYL : 6
Teet per turn : 60
Teeth per firing : 20
Mode : 1
System config
Positive input : ON
Positive output pol : ON
low level input : ON
#2 : Updated version by Perfect Power
This version takes the ignition signal from the coil signal wich is a stable square wave signal and is very strong and easily tunable
SMT6 wires ----> ECU plug number and description
POWER AND GROUND
RED >> switched power source (power to SMT6)
BLACK >> solid ground (ground to SMT6)
AFM Signal
wire must be cut to be able to change anything
cut wire end from afm connects to BLUE of the SMT6(Air metering input)
VIOLET(air metering output) from SMT6 connects to the cut end on the ecu,
Load signal
The load signal on the M20 is the AFM signal
connect the AFM signal to the BROWN (It´s now connected to BLUE and BROWN )
Ignition
Wire is the coil signal from the ecu to coil
First tap into the wire and connect it to the YELLOW wire, you should see the revs
on the software
Cut the wire and attach the end from the ecu to the YELLOW wire also connect one BLACK/BLUE wire to the YELLOW wire (this is to juice up the singal a bit for the SMT6 to be able to send out a strong signal again)
Attach the wire from the coil to the WHITE wire,
you now have control over the ignition
Global settings information for Version 2
CYL : 6
Teet per turn : 3
Teeth per firing : 1
Mode : 10
System config
Positive input : ON
Positive output pol : ON
low level input : OFF
Interlace : OFF
Installation instructions and guidelines
I personally reccomend soldering all final connections for best durability and least distortion of the signals also use shrink tubes over the soldering
Ignition installation
First you tap into the signal wire to make sure that it´s usable,
after you have come to the conclusion that is will work fine then you can cut it,
Load signal :
The E30 TPS is a switch not a variable resistance unit like later models have, altough you can retrofit one it´s not available to everybody to do so,
Thus the SMT6 uses the AFM signal as a load signal, tuning will not be as easy as with a variable one but will work nonetheless
Fuel Zero calibration :
This is used primarily when you have installed a diffrent metering device that still uses the same princible, like a maf swap,
If you swap in a MAF you can still use the zero cal. set to 0 but the map will be loaded with more numbers and may seem confusing, that´s why using the zero cal. to move the "0" in the map around to maintain a clean map helps
Note on Motronic AFM readings, it has come to my attention that the ecu reads the afm signal difrently depending on TPS switch, there is a diffrence between AFM reading when the TPS is at Partial and WOT, also idle setting,,
One trick we used first on stefáns car was to short the TPS to show the ECU idle at all times that made fuel tuning a cake, what changes it made to ignition is not known, so we do not reccomend that trick,,
General tuning
Not everybody agrees on what is the best AFR , but it seems to be close to 12.8-12.9
aiming for that AFR is a good goal,
side note on that issue : The SMT6 is designed to use a BOSCH semi wide O2 sensor and not a standard narrow sensor,,
But you can still use the voltage readings from a narrow band to lean on when doing fuel tuning, as 12.8 is about 0.88V aiming for that voltage reading from the O2 during WOT would be ideal,,
Ignition tuning,
Retard is lower then 0
Advance is greater the 0
The 0´s don´t mean that the spark comes at TDC but it comes at the pre determined time from the ECU maps, thus -1 retards 1° from stock and so on,
Hope this helps,
Please ask your questions here so that other may benfit from them and the answeres as well,,
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