00:00 |
- We're now at a point where we can proceed with the final step on our dyno which is our full power ramp run tuning.
|
00:07 |
We know that we've got our fuelling as well as our ignition dialled in pretty accurately out to 4500 RPM.
|
00:13 |
Particularly with the fuel, we'e made some guesses ahead of time about what might happen as you move past 4500 RPM.
|
00:20 |
But of course we're not going to be performing our first ramp run straight out to our 7000 RPM rev limiter, we're going to be creeping up on this.
|
00:28 |
So it'll give us the opportunity to see how close our fuelling is and make adjustments as we go.
|
00:33 |
Of course you always need to keep in mind that if at any time the fuelling is getting too lean or even perhaps excessively rich or for that matter you hear any detonation, you can always just clutch in, back out of the run, come back to idle, make the required changes and then try again.
|
00:49 |
We never want to stay in a wide open throttle ramp run if the conditions aren't ideal.
|
00:55 |
Given that this car is turbocharged does add one more complexity into the equation as well which is our boost control.
|
01:02 |
And in this worked example we're not going to be going through a thorough explanation of the process of tuning the boost control in the Ecumaster EMU Black, you'll be able to check for more details in our webinar archive for specifics around that.
|
01:17 |
However before we do get started, we want to make sure that our boost is at our minimum set point.
|
01:23 |
We've actually already done this prior to doing our steady state tuning but let's head into our boost control tab and we'll see exactly how that works.
|
01:31 |
So on the boost control tab here we've got a number of parameters.
|
01:35 |
First of all, it's important to note here that our boost control type currently is set to open loop so there's not going to be any feedback if our boost isn't hitting our target.
|
01:45 |
The Ecumaster also includes a passive boost error correction which is this table here.
|
01:51 |
And essentially this will add or subtract duty cycle to the wastegate solenoid, depending on whether we are above or below our target.
|
01:59 |
As you can see, this is also set to zero, meaning that it's not going to have any interaction.
|
02:05 |
Also just looking at our PID algorithm here, although we are set to open loop I've also zeroed all of those out, again just making sure there's going to be absolutely no interaction.
|
02:16 |
So the boost control consists of two aspects here, first of all we've got a 3D table which is our boost target versus throttle position.
|
02:24 |
We want to make sure that these numbers accurately represent the boost that we want to achieve and I've got that pretty well set up how I want.
|
02:31 |
We are targeting around 250 kPa, 4500 RPM which is about the point where we are seeing maximum boost.
|
02:39 |
And you can see in the shape of this table, I'm tapering this off quite dramatically back to the point where we're around about 210 kPa by 7000 RPM.
|
02:47 |
The reason for this is that we are limited by the fuel system capabilities here so I can't hold more boost than that.
|
02:54 |
As we go through this particular step you'll see that we'll be potentially making some changes to our boost in order to stay under our maximum injector duty cycle and make sure we've got control over our fuelling.
|
03:06 |
For now though, these boost targets are not really relevant because what we've also done is set our boost control duty cycle table here to zero so it's got no duty cycle being sent out to the wastegate so essentially we are starting our tuning here on wastegate spring pressure.
|
03:22 |
Let's head back over to our fuel table and for our first runs here what we're going to do is add a little bit of additional fuel to the wide open throttle areas of our calibration.
|
03:35 |
And we're going to do this by just highlighting in this case 180 kPa and above.
|
03:40 |
And we'll just add 2% so what we're trying to do here is just be a little bit rich as we start our tuning and remembering in particular, once we get above 4500 RPM, we're kind of into unchartered territory here so it's quite likely that our fuelling won't be right there anyway so always best to come from a case of being too rich and lean the fuelling out.
|
04:01 |
For exactly the same reason we'll head across to our ignition table and we're going to safe up our tune just a little bit by pulling a couple of degrees of timing out here above 180 kPa.
|
04:12 |
So again just starting with a safe and conservative tune as we move into our ramp runs.
|
04:19 |
Let's head across to our dyno and we'll have a look at our setup here.
|
04:22 |
On our dyno we're going to be showing manifold pressure on the top here, our air/fuel ratio in the middle, this will be in lambda units just like we're seeing in the Ecumaster and then finally of course our power at the bottom.
|
04:33 |
For our first run here let's just jump into our setup and what we want to do is select our end speed.
|
04:39 |
So you can see at the moment our end speed is going to take us out to essentially 6900, let's call it 7000 RPM.
|
04:46 |
And for our first run we want to drop that down a little bit so let's just come out to in this case 5500 RPM.
|
04:53 |
So that's 1000 RPM beyond the point that we have tuned, you could easily go a little bit more conservative than this, maybe only creep yourself out to 5000 RPM.
|
05:04 |
It's unlikely you're going to see a dramatic change in the VE table across just 500 RPM so the numbers that we've extrapolated should be relatively safe.
|
05:13 |
In this case we'll go 1000 RPM though, we'll click OK and we'll get our engine up and running here and we can perform our first run on the dyno.
|
05:32 |
Alright looking at our dyno screen here we can see we've ended up with 243 horsepower at the wheels, not really too worried about our peak power right now, just getting our fuelling and then we'll move onto our ignition timing under control.
|
05:45 |
Looking at our boost, we can see that we're running around about 10-12 psi, a little bit of a creep up here at higher RPM.
|
05:53 |
Our air/fuel ratio, our lambda there, not specifically anything wrong with that, we are a little bit leaner than what we would like here through our spool up phase and as we move through the rev range and the boost gets up we can see we're actually probably a little bit richer than expected.
|
06:09 |
To get a bit more detail on that though, let's jump into our tuning software and we'll have a quick look in here.
|
06:16 |
For a start here we can see in our top set of graphs, we've got our RPM and our boost pressure, our RPM peaking at 5700 RPM so just a touch over what we've actually got set on the dyno.
|
06:26 |
We can see that the boost spiked up a little bit as the dyno locked down there and clamped the RPM up to 205 kPa, we can see through the most, we're around about 190 kPa.
|
06:37 |
What we're more interested in right now though is our lambda and we can see our air/fuel ratio or lambda versus our target.
|
06:44 |
And we can see this area through here, from around about 3000 RPM up to around about 4200 RPM.
|
06:51 |
We're actually a little bit leaner than our target.
|
06:54 |
And then as we move through from around about 4700 RPM, so as we move past our area that we've tuned, we can see that we actually move a little bit richer than our desired target down to around about 0.84 lambda, 5500 RPM.
|
07:09 |
So we can correct that using this graph, so let's start by leaving our ignition timing exactly where it was, I was listening for knock during that run, there was no knock audible so we're going to get our fuelling dialled in first.
|
07:22 |
So let's have a look at our fuel table here and for a start we want to correct this area down during the spool up.
|
07:31 |
So we can see that this actually starts around about 2800 RPM, 2900 RPM, we can use the cross hairs on our table to see where abouts that was.
|
07:41 |
And basically from about 120 kPa, 3000 RPM, through to around about 4500 RPM and in this case 200 kPa we want to add some fuel.
|
07:54 |
We're going to actually add that in above as well.
|
07:58 |
And the reason that I'm going to do this is because I'm expecting that if we are a little bit lean through that area, at the moment where we're not controlling the boost on wastegate spring pressure, that's probably going to continue as we move above that as well.
|
08:12 |
So we'll come down to our 120 kPa site.
|
08:15 |
We'll just add 2% to start with there and I'm actually going to add a little bit more down in the lower RPM range up to about 3500 because we can see up to around about 3600 RPM here we are a little bit lean.
|
08:31 |
So I've added 4% in there, we can of course use our have over want calculation and a percentage change there.
|
08:39 |
For our first change there we'll just leave that at what I've changed.
|
08:42 |
Looking at what happens there, above 5000 RPM, we're around about 2% too rich.
|
08:48 |
Up to about 5500 RPM so 4500 is looking pretty good so 5000 and 5500 RPM we're about 2% rich.
|
08:59 |
What I"m going to do is actually highlight the entire RPM row so remembering here all we've done is extrapolated our results across so essentially if we're too rich at wide open throttle and on positive boost, we're going to expect that that change will be the same through the rest of our map as well so what we'll do here is start by removing in this case 3% here, so we'll multiply by 0.97.
|
09:19 |
So that's taken us up to 5750 RPM, we'll go back into our graph and we'll see what we've got there.
|
09:26 |
5750, we are around about 5% too rich there so what I'm going to do is multiply the entire table out above that as well, again just expecting that the trends that we're seeing will continue so we'll take that by 0.95, multiply that out and we'll make that change.
|
09:46 |
So for now we're not making any changes to our boost, we're also not making any changes to our ignition timing.
|
09:51 |
We want to get our run all the way out to 7000 RPM with control over our fuelling and then we'll move on and have a look at our ignition timing.
|
09:58 |
So let's get another run underway.
|
10:00 |
This time we're going to extend our RPM range out by another 1000 RPM.
|
10:04 |
we'll go out to 6500.
|
10:35 |
Alright we've got our second run complete there, we can see on the dyno screen, this time 269 horsepower.
|
10:41 |
Again still not really that interested in the power itself, it's just getting our tune dialled in.
|
10:46 |
We can see that our boost is starting to creep up a little bit at higher RPM.
|
10:49 |
Pretty typical, we're not necessarily going to end up with a rock solid stable line for our boost control so nothing out of the ordinary.
|
10:56 |
We're seeing, as that boost is creeping up, our air/fuel ratio is tracking a little bit richer at higher RPM.
|
11:02 |
We've got this reference line in here at 0.78.
|
11:05 |
Ultimately that's about my target once we are under higher boost pressure.
|
11:09 |
For a better idea of what's going on though, let's jump back into the laptop software again and again we can see what's going on here.
|
11:16 |
Our RPM has gone out to exactly what we asked for this time, 6500 RPM.
|
11:21 |
You can see the boost spiked up to 210 kPa there at higher RPM.
|
11:25 |
Looking at our air/fuel ratio, we've still got a slight lean area which we can work on here, not too bad this time but around about 3000 RPM through to about 4000 RPM.
|
11:36 |
A little bit leaner than our target.
|
11:38 |
We can see for the most part there just that one change we have made, we're within about 1% of our target now until we get up to about 6100 RPM where we drop a little bit rich so let's just have a look at that area first.
|
11:51 |
So from about 6100 RPM, let's call it 6000 RPM and above, 200 kPa, we are around about 2% rich so we'll make that change there.
|
12:03 |
We'll highlight to 6000 RPM, again in these untuned areas where we've just extrapolated, we're making any changes to the entire table here.
|
12:11 |
So what we'll do is we'll take out, in this case 3%.
|
12:14 |
I'm just over estimating very slightly here based on how I know the ECU is responding.
|
12:19 |
Through 5500, 5700 RPM, probably no real need to make a change there but just to be fussy, let's make another change there of 1% so 0.99, multiply, that's going to fix that up.
|
12:35 |
Now looking here, we are a little bit variable from 3000 RPM.
|
12:40 |
At this particular point we're about 3-4% lean.
|
12:44 |
We drop to a point where we're only 2% lean here and then again at 3650 RPM we're about 6% lean so what we can do is focus on that.
|
12:55 |
I'm not this time going to make changes all the way out here, I'm going to be a little bit more specific so we can see where exactly we are running.
|
13:03 |
Particularly here in this 97.7% cell at 160 kPa and we're also transitioning up here a little bit as well so what I'll do is we'll make a change here, we'll make a change of 1.06, multiply that by that.
|
13:24 |
I'm also going to just smooth these numbers here so I've got some consistency as we've created a bit of a spike in here which probably isn't going to be very realistic so we'll use our vertical interpolation there to correct that.
|
13:37 |
Now we're also going to increase our value here at 180 kPa because we're just starting to interpolate across from that and we'll probably just for the sake of it there add a couple of percent to that cell and also a couple of percent to our neighbouring cell.
|
13:53 |
So that's going to take care, hopefully of our 3750 RPM zone.
|
13:59 |
Come down a little bit to 3500 RPM, we're not too bad here but a little bit lean so we're basically going between these two cells here.
|
14:07 |
So what we'll do there is add just a couple or percent, we're only a little bit lean there.
|
14:12 |
And then we come down further.
|
14:14 |
This particular cell here at 3000 RPM, we are around about 4% lean so let's just make a change there, I'm actually going to extrapolate that up as well.
|
14:25 |
And we will just add a couple of percent into our 100 kPa cell here.
|
14:31 |
Of course we can always come back and revisit some of these sites under steady state conditions if we do end up making dramatic changes here.
|
14:37 |
So for the moment, looks like we've got a fresh set of adjustments to work from, let's just make those changes there permanent and let's get up and running, we'll perform another ramp run on the dyno.
|
15:29 |
Alright we've got our third run complete there and we can see our power realistically hasn't changed.
|
15:34 |
We have this time extended our RPM range right out to 7000.
|
15:38 |
We're comfortable with what the fuelling was doing on our last run so no reason not to go that little bit further.
|
15:43 |
We can see that our fuelling's looking pretty good here, our boost pressure still climbing a little bit as our RPM comes up, let's jump back into the Ecumaster log and we'll see exactly what we had going on.
|
15:53 |
We can see that we've got to 7000 RPM, peak boost there of just under 210 kPa again spiking slightly after the dyno's clamped and started to pull the RPM back down.
|
16:06 |
Looking at our fuelling you can see that just with those couple of iterations of changes there, our fuelling's really quite close now.
|
16:12 |
Potential that we could do a little bit more work here during that spool up area but realistically this is absolutely fine, there's nothing wrong with that.
|
16:20 |
We are just moving very slightly rich here as we go above 6500 into 7000 RPM.
|
16:28 |
So we will address that, although realistically, it's already pretty good so what we can do here is we'll highlight 7000 RPM and above and in this case I'll just take 1% fuel out, 0.99 our multiplication symbol, and we're good to go.
|
16:43 |
So everything's looking OK there.
|
16:46 |
The next step of course is to increase our ignition timing, remembering that we have already pulled a couple of degrees out there from 180 kPa and above.
|
16:54 |
And we can see that our boost pressure is essentially at or above 180 kPa from around about 4000 RPM.
|
17:03 |
So let's head back over to our ignition table and we'll highlight the entire table there in the area that we did change and we'll add our 2° back in.
|
17:13 |
Now what we're going to do is perform another ramp run and we're going to compare to the data we've already got on the screen.
|
17:19 |
Obviously, just like our steady state tuning, we're expecting that any time we're adding ignition timing and moving towards MBT, we are going to end up with an increase in both power and torque so let's get our engine back up and running, we'll perform another ramp run, obviously as we're doing this, being more cautious listening for detonation and we'll see what our results are.
|
17:58 |
Alright with our run complete there, we can see that we have picked up a small amount of power but has been relatively minimal, we've gone from 269 horsepower to 273.
|
18:09 |
In particular during the spool up area there, up to around about 4000, maybe 4250 RPM, we really didn't see any noticeable improvement in our engine power.
|
18:20 |
The more improvement we saw was towards the higher RPM range.
|
18:24 |
We did have no knock present so what we're going to do is learn from that and we're going to make some further changes.
|
18:30 |
Before we do that though, let's just have a quick look at our graph, our logs, we obviously want to always make sure when we're comparing data like this that our operating conditions are the same.
|
18:41 |
So in particular we always want to try and start our ramp runs with the same engine coolant temperature and intake air temperature and we can see here, we're operating around 89° during this ramp run and about 20 to 24° intake air temperature so nothing wrong with that.
|
18:57 |
Our boost pressure, still comparable to our last run which is what we'd expect so nothing untoward there.
|
19:02 |
Also just having a quick look over our fuelling, we can see that our fuelling is within about a percent of where we want it so no need to make any changes.
|
19:09 |
What I'm actually going to do here is highlight the timing that we've just added in and up to 3500 RPM, what I'm going to do is actually take one of those degrees back out, we didn't see much of an improvement as I mentioned there.
|
19:23 |
If we want to really get granular with it, there was a mild improvement.
|
19:26 |
There's no knock but just to be a little bit on the safe side, if I'm not really seeing any improvement, I'd prefer to be conservative with my tiiming.
|
19:33 |
3750 RPM I'm going to leave the timing where it is now.
|
19:38 |
In order to do that, at 4500 RPM, I will highlight down to 180 kPa, we'll add 1°.
|
19:44 |
As we go above here though, remembering that we've only extrapolated our results at this point from 4500 RPM and above so I'm going to highlight the entire table all the way down to our low vacuum loads and we'll add another 2° there.
|
19:59 |
Let's get another run underway and we'll see what the results of that change to that timing has been.
|
20:26 |
Again we've seen an improvement in our power, we're up to 279.5 horsepower.
|
20:30 |
Looking at that during that ramp run we could see that again our gains were more dramatic at higher RPM, we didn't really see much of a change up to around about 5000 RPM.
|
20:41 |
So what I'm going to do there is make a further change, from 5750 RPM and above we're going to add one further degree and then we'll extrapolate that down and add another further degree at 5500 RPM.
|
20:55 |
Let's get another run underway and we'll see the effect of that change.
|
21:17 |
Alright our last change there, we've seen another improvement from around about the 5000 RPM point, 5500 remember where we started adding that additional timing and we're up to 213.2 KW at this point.
|
21:32 |
Now this is just an iterative approach, what we're going to do is continue going with this until we either find that we see no gain in our power and torque, in which case we can pull the timing back out.
|
21:42 |
If it doesn't give us an improvement there's no need to have it.
|
21:44 |
Or alternatively we will get to the knock threshold in which case we want to retard the timing.
|
21:49 |
We're actually at that point now, we've already tested and found that if we go any further than this, we will see a small improvement in our power but at the expense of knock so we're going to leave our timing set where it is right now.
|
22:02 |
What we'll do is we'll make those changes permanent and we'll just have a quick look at our table graphically as well just to make sure that we do have a reasonably consistent trend in that table.
|
22:15 |
That's exactly what we've got at the moment so that's all looking pretty much as I'd expect.
|
22:19 |
Having a look at our graph, we've still got pretty good control over our fuelling so nothing untoward going on there.
|
22:25 |
We do also want to just pay attention here to our injector duty cycle in brown.
|
22:30 |
So we can see that that's peaking at 78.5%.
|
22:33 |
A little bit of headroom there but as we'll soon see, there is a limit to what we can do.
|
22:38 |
The next step with our process that we're going to cover off during this particular part of the tuning is we're going to make some changes to our boost control.
|
22:47 |
What we want to do is creep up on our boost target.
|
22:51 |
We're going to be targeting around about 250 kPa, around about 4500 RPM.
|
22:56 |
But at higher RPM in order to maintain our headroom with our injectors, we're going to be probably tapering the boost down pretty close to what we've got right now.
|
23:06 |
So let's have a look at how we can do that.
|
23:10 |
Alright we've got our boost target table here and I've already got this pretty well set up as I've mentioned so this is probably going to be pretty well the targets that we're going to be looking for.
|
23:20 |
What we now need to do is add some duty cycle to our duty cycle table in order to actually get us onto that target.
|
23:26 |
We've got manifold pressure at the moment as our load axis here.
|
23:30 |
Not really too relevant for our example, we're just going to be treating this entire table as a 2D table.
|
23:37 |
When we are doing this, we want to creep up on our results so what we're going to do for a start is just highlight the entire table, and we'll set it to a value of 25%.
|
23:46 |
What we want to do is just see or gauge the magnitude of the result that that change in duty cycle is going to give us.
|
23:54 |
We've made it across the board for the moment so let's perform another run, obviously also monitoring our fuelling and knock as we're going to now be moving into an untuned area on our fuel and ignition tables.
|
24:04 |
Let's see what that's given us.
|
24:27 |
Alright so straight away we can see that we've got a reasonable improvement in our power, we've gone up to 311 horsepower at the wheels now.
|
24:34 |
We can see our boost did increase, we saw that live overlaid on top of the last plot.
|
24:39 |
We can see our boost is peaking around about 4500, 4800 RPM before falling away slightly as the RPM comes up.
|
24:47 |
So it's a natural progression with the wastegate as we start working the turbocharger harder.
|
24:52 |
Let's jump into our tuning software and we'll have a quick look at what those results actually look like.
|
24:57 |
First of all we always want to be monitoring our fuelling and our ignition timing so we can see our fuelling's actually tracked quite nicely there.
|
25:05 |
We're still within about 1% of our target so no need to make any changes.
|
25:09 |
Our boost showing here, peak of 240 kPa falling away to around about 225, 224 kPa.
|
25:18 |
We do need to monitor here our injector duty cycle so you can see straight away we're starting to get up around about 87.5% peak, it's about as far as I'd want to push the injectors.
|
25:31 |
If we go much further we can start getting inconsistencies in our fuelling so we probably don't have too much further that we can go at higher RPM however we can work a little bit more boost into our mid range in part throttle here.
|
25:46 |
Now monitoring for our ignition timing there, no knock activity going on and of course as we step up in our boost, we can choose to try advancing our timing a little bit or retard our timing and just see how everything's tracking.
|
25:58 |
For the purposes of this demonstration, we're going to jump ahead though and we're just going to make a further change to our boost so we'll head across there.
|
26:05 |
So we know that right up in the high RPM ranges here we're probably there or thereabouts in terms of the boost we want to run.
|
26:12 |
However what we can do is get a gain in our boost response, sometimes by increasing the duty cycle below the boost threshold, so where the turbocharger can't make full boost, making sure that we are in fact holding the wastegate completely closed.
|
26:27 |
So let's try that, we'll increase the numbers up to 3200 RPM there, up to 90%.
|
26:31 |
What I'm going to do now is make a further change through here of another 10% so we'll add 10% up to 4500 RPM and then we'll taper that change that we've just made down here, we'll use our vertical interpolation function, control L to smooth that table out.
|
26:51 |
Let's get another run underway and we'll see the effect of that change.
|
27:10 |
Alright so we've got our last run up there on the screen now, very small improvement through the mid range there which is exactly what we'd expect from increasing the boost so everything's pretty well worked exactly like we'd expect.
|
27:23 |
312 horsepower, 232 kW is about as much as we can safely expect from the existing fuel system so unfortunately at the moment, we've got more turbo equipped on this turbo than we do have fuel system to support it so it's all about being conservative and keeping the fuelling under control so that our engine is going to remain reliable.
|
27:41 |
Let's jump into the laptop software and we'll have a quick look at what we've got here.
|
27:45 |
What we can see straight away is our peak boost sitting at 240 kPa, it's dropped back to exactly what we saw previously, remembering that we didn't make any duty cycle adjustments at higher RPM.
|
27:57 |
So possibly we could push this a little bit further, originally we were intending for around 250 kPa but at this point I've got a nice safe tune, we've got good control over our boost and I'm pretty comfortable with where we're at.
|
28:10 |
Let's look at our fuelling here and we can see that we've got good control over the fuelling, we haven't actually needed to make any adjustments to that VE table as we've increased the boost so our initial shape and form that we had into that VE table has actually proven to be pretty well on point.
|
28:27 |
We've still got our maximum injector duty cycle here sitting at 87.5% so again we're there or thereabouts in terms of maximum injector duty cycle, 85-90% is about as much as I'd like to push and realistically the sort of improvements in power that we're going to see with an additional 2.5% injector duty cycle, really probably not warranted at this point.
|
28:49 |
Now obviously right now we have only done a very simple and initial setup with our boost control just to show you the way the engine responds to boost and how we can deal with this with our fuelling and ignition timing more so than an actual in depth step by step process of setting up boost control on the Ecumaster, as I mentioned, we will be covering this in some webinars if you want more details.
|
29:14 |
At this point, our tuning on the dyno is complete, I'm comfortable with my results, we've got the sort of power and torque that I'd be expecting for this combination, we've got control over everything, we'll now move onto our last step where we can confirm everything we've seen on the dyno out on the road under real world conditions.
|