Tuning an engine with a programmable ECU
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Tuning an engine with a programmable ECU
Hi all,
Just a few notes on the tunability of the CNK ECU and how to tune an engine <BASIC ROAD TUNING> --- before we start I want to mention that there are many ways to do road tuning, this is just one of the methods I use depending on the ECU and circumstance.
Right firstly - the CNK ECU is very similar to the SMT6 unit - it uses the same software, and harness, but has definite changes that are customized to my requirements. All diagrams for the relevant cars will be supplied with technical information not usually included with the SMT6 product that relates to the ignition interface of the Hyundai sensors and ignition pickups.
In the software you will see it has been branded CNK, and the maps I supply are protected so that you cannot overwrite or modify them. If you want a map with different settings, you will have to create a new one from scratch. I will also supply a blank map with only the global settings entered in so that all you need to do is tune the fueling and ignition values.
OK - having said this, tuning an engine on the road is simple. I will outline this briefly using the CNK ECU, remember that this ECU is a PIGGY BACK ECU, and different tuning techniques are used for piggy back systems compared to Stand alone setups because with the piggy back setup you already have a base map that runs the engine, you just have to tweak it. Stand alone setups have nothing entered into them and you need to create the entire fuel and ignition map from scratch.
Once the install is done and working assuming that no values for fuel or ignition have been entered, the car should start and run perfectly as if no PB <piggy back> system has been installed - this will be because none of the stock fuel or ignition values have been modified, all that is happening is that the signals that the CNK ECU has intercepted have not been modified at all, and are simply being relayed to the Engine as per normal operation.
OK, for this excercise you will need two things:-
1) Tools:- the tools you WILL need for sucessful tuning is a WIDEBAND oxygen sensor unit, this will allow you to run accurate AF tuning whilst on the road at cruise or WOT.
2) A baseline - this is a map to start tuning against (a starting point or referrence point), get the car onto a dyno just for a run in 4th gear to see a power graph and if possible an A/F print out aswell before tuning.
For example - the Delta V6 engine is tuned PIG RICH from the factory and at certain RPM points runs up to 11.1 A/F ratio (at WOT) - on a stock engine this is very rich! This is also part of the reason that there is a dip in the power and torque curve around 5000RPM. What we want to do in this example is lean out the mixture slightly to around 13 A/F ratio - remember this engine is normally aspirated and does not need to run such rich mixtures as compared to turbocharged engines.
If your dyno session was not able to provide you with an A/F printout, then you can plot your own as follows:- assuming we have our W/band unit hooked and up running, we start to plot our baseline. In order to do this correctly and accurately, we would need to take the car on a LONG, open, flat road, and in a high gear preferrably 5th gear at WOT from around 2800RPM onwards.
The reason we choose a high gear is so that the engine does not rev fast - this will allow us to see the fueling values at RPM points on the W/Band unit easily without the engine changing RPM too fast.
Once you are at 2800RM in 5th gear, put your foot down flat, check the WB unit and record the fuel mixture, write it down. Then progress to 3000RPM, open the throttle and record the mixture, then go to 3500RPM and open the throttle, record the mixture. Do this again and again till you have the mixtures up to 6000RPM IF you can get there on a flat road.
Once you have written down all the values, you will be able to draw yourself a graph and see what the curve looks like, Excel is helpful here.
This is actually similar to what a dyno does to record the mixtures that it prints onto the dyno printout.
Once you have determined what part of the graph you want to change, you can get back onto the road and decide where to start tuning from (what RPM) Get up to the RPM you wish to change a fuel value and open the throttle, check the W/band unit and confirm the mixture according to the baseline to make sure you have it all correct.
Now still while driving, enter in a fuel value either more fuel or less fuel, and then open the throttle at that RPM again, and check the change. If the mixtures changed according to your intension, then continue to the next RPM point you want to make a change and repeat the steps. If the mixture did not change accordingly, continue to make fuel value changes until the mixture is where you want it to be.
Once your tuning is done, repeat the baselne procedure and draw your graph once more, overlay the graphs ontop of one-another and check the differences. Get back to the dyno for a run to compare power and torque, this will show true reflection of your efforts. If you could get an A/F printout on the revised run, you could see how accurate the self plotting with the W/band unit was on the road - your A/F values should be almost dentical to the dyno printout.
Well - hope this helps in any way it possibly can. For those of you that have got your engines started and idling with a stand alone system, this is the best way to learn about tuning, and also to get your car unning to around 95% of where it possibly can, you will need to get to the dyno to complete fine tuning --- there is more to this technique though.
Just a few notes on the tunability of the CNK ECU and how to tune an engine <BASIC ROAD TUNING> --- before we start I want to mention that there are many ways to do road tuning, this is just one of the methods I use depending on the ECU and circumstance.
Right firstly - the CNK ECU is very similar to the SMT6 unit - it uses the same software, and harness, but has definite changes that are customized to my requirements. All diagrams for the relevant cars will be supplied with technical information not usually included with the SMT6 product that relates to the ignition interface of the Hyundai sensors and ignition pickups.
In the software you will see it has been branded CNK, and the maps I supply are protected so that you cannot overwrite or modify them. If you want a map with different settings, you will have to create a new one from scratch. I will also supply a blank map with only the global settings entered in so that all you need to do is tune the fueling and ignition values.
OK - having said this, tuning an engine on the road is simple. I will outline this briefly using the CNK ECU, remember that this ECU is a PIGGY BACK ECU, and different tuning techniques are used for piggy back systems compared to Stand alone setups because with the piggy back setup you already have a base map that runs the engine, you just have to tweak it. Stand alone setups have nothing entered into them and you need to create the entire fuel and ignition map from scratch.
Once the install is done and working assuming that no values for fuel or ignition have been entered, the car should start and run perfectly as if no PB <piggy back> system has been installed - this will be because none of the stock fuel or ignition values have been modified, all that is happening is that the signals that the CNK ECU has intercepted have not been modified at all, and are simply being relayed to the Engine as per normal operation.
OK, for this excercise you will need two things:-
1) Tools:- the tools you WILL need for sucessful tuning is a WIDEBAND oxygen sensor unit, this will allow you to run accurate AF tuning whilst on the road at cruise or WOT.
2) A baseline - this is a map to start tuning against (a starting point or referrence point), get the car onto a dyno just for a run in 4th gear to see a power graph and if possible an A/F print out aswell before tuning.
For example - the Delta V6 engine is tuned PIG RICH from the factory and at certain RPM points runs up to 11.1 A/F ratio (at WOT) - on a stock engine this is very rich! This is also part of the reason that there is a dip in the power and torque curve around 5000RPM. What we want to do in this example is lean out the mixture slightly to around 13 A/F ratio - remember this engine is normally aspirated and does not need to run such rich mixtures as compared to turbocharged engines.
If your dyno session was not able to provide you with an A/F printout, then you can plot your own as follows:- assuming we have our W/band unit hooked and up running, we start to plot our baseline. In order to do this correctly and accurately, we would need to take the car on a LONG, open, flat road, and in a high gear preferrably 5th gear at WOT from around 2800RPM onwards.
The reason we choose a high gear is so that the engine does not rev fast - this will allow us to see the fueling values at RPM points on the W/Band unit easily without the engine changing RPM too fast.
Once you are at 2800RM in 5th gear, put your foot down flat, check the WB unit and record the fuel mixture, write it down. Then progress to 3000RPM, open the throttle and record the mixture, then go to 3500RPM and open the throttle, record the mixture. Do this again and again till you have the mixtures up to 6000RPM IF you can get there on a flat road.
Once you have written down all the values, you will be able to draw yourself a graph and see what the curve looks like, Excel is helpful here.
This is actually similar to what a dyno does to record the mixtures that it prints onto the dyno printout.
Once you have determined what part of the graph you want to change, you can get back onto the road and decide where to start tuning from (what RPM) Get up to the RPM you wish to change a fuel value and open the throttle, check the W/band unit and confirm the mixture according to the baseline to make sure you have it all correct.
Now still while driving, enter in a fuel value either more fuel or less fuel, and then open the throttle at that RPM again, and check the change. If the mixtures changed according to your intension, then continue to the next RPM point you want to make a change and repeat the steps. If the mixture did not change accordingly, continue to make fuel value changes until the mixture is where you want it to be.
Once your tuning is done, repeat the baselne procedure and draw your graph once more, overlay the graphs ontop of one-another and check the differences. Get back to the dyno for a run to compare power and torque, this will show true reflection of your efforts. If you could get an A/F printout on the revised run, you could see how accurate the self plotting with the W/band unit was on the road - your A/F values should be almost dentical to the dyno printout.
Well - hope this helps in any way it possibly can. For those of you that have got your engines started and idling with a stand alone system, this is the best way to learn about tuning, and also to get your car unning to around 95% of where it possibly can, you will need to get to the dyno to complete fine tuning --- there is more to this technique though.
