- We've finally got to a point where we could start the engine for the first time
and I've been through this a number of times with both my own projects and those that
we've built for other people.
There's a lot of work goes in behind the scenes to get up to the point where you can start the
engine for the first time and I think everyone starts to get a little bit sick and tired of that
process, you start to lose a little bit of enthusiasm and a little bit of momentum
but the second you hear the engine run for the first time, it really just rejuvenates everyone
and you can get back into pushing to the finish line.
So the process of getting the engine up and running requires first of all a full
systems check.
Obviously as you've seen, we've made a complete new wiring harness and it's a
pretty complex harness, easily the most complex harness I've built in my time.
And it's a systems check here to just make sure that every input and output is
working properly.
What we do here is go through and configure all of the inputs in the MoTeC M150 ECU and
ensure that they're all reading correctly.
Did actually find a couple of small issues there, nothing too difficult to fix, probably
comes from pinning out the connectors at about 2 o'clock in the morning.
Sleep is definitely a friend when you're working on something that is so complex.
Anyway once we go that all sorted out, we could also test the outputs and here
what we do is simply put the MoTeC M1 ECU into a test mode and we can pulse each
of the injector outputs.
it's important to make sure that they are, first of all functioning as expected and
secondly we want to make sure that for example, the injectors on cylinder one are
in fact located on cylinder one.
That can play havoc with problems down the track, exactly the same situation with our
coils, want to make sure that they're firing and that they are assigned to the correct
cylinder.
The next step is to set up our ref and sync inputs to the ECU.
And what we're doing here is basically giving the ECU information about engine
position and engine speed.
We've got a 60 - 2 crank trigger wheel from Mazworx, we've got a single sync input,
again from Mazworx, it was simply a case of configuring the reluctor pickup for the crank
in the software and the hall effect sensor for the sync, again in the software.
A nice feature with the MoTeC M1 ECU, it's not that uncommon these days,
is it does feature a built in scope.
So what we can do there is essentially disable fuel and spark so there's no chance
that the engine's going to try and fire, we can crank the engine over and physically make sure
that the signals the ECU is getting are correct.
With the reluctor or magnetic pickup on the crank in particular, that's really important
because we can actually make the engine run with the polarity around the right way
but we're going to end up suffering from timing drift so important to make sure that
that's all dialled in, it was, also making sure that the sync input is occurring in the
correct place.
Essentially with the missing tooth trigger wheel, the place we don't want it to occur
is near that missing tooth, essentially anywhere away from that we're going to be OK and the
ECU can easily define or decide where abouts in the engine cycle it is.
Once we did that, before we tried to start the engine, we also set up our Snap-On
digital timing light and checked our base ignition timing.
So this is just a process of making sure that the numbers we're seeing on the laptop screen
actually match what is being delivered to the engine.
Now the problem with doing this is at cranking speed we're not going to get an
absolutely rock solid signal so it's always a case of doing a rough approximation
at cranking speed and then once we've got to a point where the engine's actually
up and running, we can come back, revisit this and be a lot more accurate
because the base timing is absolutely critical for engine reliability.
If that's not right, we can end up with the engine getting much more or much less
timing than we think from the laptop screen numbers.
Now one thing that did actually catch me out here and it becomes a bit of a
coin toss, a bit of a lottery here as to whether you'll be right or wrong, but when you're
setting the timing, you can end up with the timing being correct on either the compression
stroke, which is where we want it to be, or alternatively the exhaust stroke.
Which means that it's simply 360° out.
So Murphy's law here, I got this wrong and that was literally the only thing that stopped
us starting it up straight away, basically cranked the engine and there was just
nothing, no popping, no sign of life.
Figured that out pretty quickly because I've been here a number of times before,
simply added 360° to the crip value in the MoTeC which defines the base timing and
it literally started up straight away so that was actually pretty promising and really
in terms of a fresh engine start up, no big issues.
Once we had the engine running, we can do some systems checks there,
make sure that the alternator's charging, make sure that we've got good oil pressure,
and all of those sorts of things which are also checked out.
At this point, we don't really want to spend too much time running the engine though,
we want to really get the engine loaded up on the dyno so we can start breaking
in the rings, nothing worse than letting a freshly built engine run at idle,
particularly when it's at operating temperature.
We can get into a situation here where we end up with the bores glazing.
Once that happens it's basically going to be impossible for us to get the rings to
seal properly so it's really important to get the engine under a little bit of
light load very quickly.
Once we were comfortable with everything, we finished off a few last little jobs and we
got the car onto the Mainline prohub dyno for the run in.
Now there's a lot of misconception and misunderstanding about the break in process.
I hear a lot of engine builders recommending 1000 km of gentle running, even 5000 km
of gentle running.
The reality is with modern rings and modern honing techniques, we don't need anything
like that.
We went through a couple of hours of light load running, revving the engine RPM between about
2000 and about 4000 RPM and cycling between periods of light load where we bring the engine
onto boost, perhaps one to three psi of boost, and then backing off back into vacuum.
And what this does is when we apply positive boost, or load to the engine, this, the
combustion pressure here forces the rings out against the cylinder wall.
And this helps them bed in.
We do need to be mindful though because that fresh hone pattern is pretty rough
and if we just held the engine under sustained high load and high RPM, we're going to
generate a lot of heat so this is why we keep the control over how long we're
loading the engine for as well as the RPM that we're using.
As we go through the break in process, we'll gradually add more RPM and more
load while we're still varying that.
The break in process, also we completed using a mineral grade oil.
Once the break in's complete we change both the oil and filter and run a good high quality
synthetic oil.
With the break in process out of the way, it's time for the fun part which is the tuning.
Now actually a little bit of the tuning process actually gets completed during the break in
because we get to fill in both the fuel and ignition timing values in the areas that
we're accessing.
This builds up a bit of a picture of what those maps look like.
And both the fuel and ignition maps will have relatively smooth and consistent
trends so we start to extrapolate the numbers from the areas we have tuned, out into the
areas we haven't tuned.
And this means that when we start adding more boost, more RPM or both, as we move
out into those untuned areas, we're already going to be pretty close because we've
extrapolated those general trends which means that our tuning process is really
safe, we're not putting a huge amount of undue stress and strain on the engine
and we don't need to hold it in an untuned area where perhaps it's got too much timing
or not enough fuel for an extended period of time while we're dialling that in.
The other aspect that makes my life a little bit easier here is that the MoTeC M1 runs
a lambda to CAN unit, giving the ECU air/fuel ratio or lambda data.
And it uses a function called quick lambda.
Essentially what this means is that all we need to do is drive into the centre of a cell,
hold the engine in steady state until the air/fuel ratio stabilises, press the Q key
and that'll take us straight onto our target lambda.
I'm not usually a fan of automatic tuning processes but this is one that I've found
repeatedly works exceptionally well.
And it does speed up the tuning process.
Once we got into the tuning a little bit further, we quickly found that the Garrett
GTX3076R gen 2 turbo was proving to be incredibly laggy but laggy to the point where
we were confident something wasn't quite right.
We weren't seeing 10 psi of boost pressure until around about 5500 to 6000 RPM
and obviously as we increase the boost using the wastegate duty cycle through the boost
control solenoid, things didn't get any better.
Now given that I've seen this sort of situation before, one of the key thoughts in my mind
was that the seat had been left out of the Turbosmart wastegate when it had been
installed and this is easy to do, I've seen this so many times.
Particularly it's easy to do when we've had a lot of people working on the car
and these parts have been installed, removed, installed again multiple times.
Fortunately with the location of that wastegate it was a pretty easy task to pop the gate
off and have a look and sure enough, the wastegate seat was missing.
Reinstalled that, got it back onto the dyno and straight away we had much
better boost response with our boost all in by around about 4400 RPM.
Now that is still reasonably laggy however the benefit we've seen here with the SR20VE
cylinder head or the VVL cylinder head and the Kelford cams we're running is that it
loves to rev.
And we're running it out to about 8800 RPM at the moment and the power is actually
still climbing slightly.
Given that we are going to be endurance racing this, I wasn't too keen on pushing the
RPM too much further, a 9000 RPM powerband or upper rev limit is
certainly going to be sufficient for what we need on the track and that gives us
a fairly wide powerband to utilise, particularly when it's coupled with the sequential six
speed gearbox from TTi, the ratios are very short, meaning that when we change
gear we don't really drop too far in the rev range so the only time we're going to be
down around 4000 maybe 4500 RPM is when we're coming out of a low speed
hairpin and at that point we really don't need any more torque anyway so we're
pretty comfortable that it's going to be workable but at a later point we may also
try swapping to a smaller AR exhaust housing.
At the moment we're running a 1.01, we might try dropping that to a 0.84
and see what that puts us up in terms of boost response and alternatively whether
that hampers out top end power.
In terms of the power itself, we're taught the whole way through that the GTX turbo
that we're running is capable of about 650 horsepower.
At this point though, we're mere days away from our first event.
We've got a lot of unknowns with the whole package and we certainly don't need
650 horsepower to go racing.
So we've purposefully been a little bit cautious with the boost and hence the
power levels that we're running.
What we did initially was we tuned the engine on pump gas and this allowed me
to set up the knock control.
We ran it up to 20 psi on pump gas and it was already making pretty impressive numbers.
We then switched over to E85, set up the flex fuel strategy in the MoTeC M1 which
was really seamless and on E85 we've set our boost pressure at multiple levels,
we've got a steering wheel switch that the driver can use to adjust that and essentially
the base duty cycle, the base boost pressure I should say is 10 psi, that's just the wastegate
spring pressure.
From there we step up to 12 to 15, 18, 20 psi and then we've also got a push
to pass button that takes us up to 24 psi.
On the base boost pressure at 10 psi we're making 385 horse at the rear wheels which
coincidentally was around about the same power that we're making on the V8.
So we're probably going to be pretty competitive with our lap times, even at that base boost
pressure.
10 psi as well, we're not really putting a lot of stress on any component in that engine
so I'm expecting reasonably good reliability if we can run it that low.
Essentially for endurance racing we want to use the lowest power setting we can
in order to get the lap times that we need in order to be class competitive.
It remains to be seen where that needs to be.
Stepping up to the upper level, at the higher point with our push to pass setting,
24 psi, we're 593.5, let's called it 594 horsepower, so just a little bit shy of
600 horsepower at the rear wheels.
This is still a pretty conservative tune as well, we're not feeding a lot of timing
into it.
Even at that point, depending on what sort of conversion factor you want to use for our
hub dyno, probably safe to say that we're sitting around about 620 flywheel
horsepower so certainly not too shabby from a little two litre engine.
Now let's have a look in the cockpit and I'll show you how those boost settings are
adjusted.
Here we've got our steering wheel and on the left hand side we've got our traction control
setting and we utilised this last season.
On the right hand side we've got what was initially set up as a launch control knob
but we run standing starts in this class so wasn't actually used.
But if we come up and have a look at the dash here, on the bottom line we can see
we've got our traction control settings which we've just looked at and on the right hand
side I've now set this up as a boost map so we've got zero through to four,
remembering our zero setting that is 10 psi, setting four we're on 20 psi.
And we've also got this button here which at the moment is labelled lights so we're
going to use this for a headlight flasher but at the moment we're using it for a
push to pass so let's have a look at the dash again and see how that works.
So when we press that, it brings up a little warning to the driver saying party time,
so we know it's game on.
Now I've set this up so it latches with the throttle as well so we only need to press
the button once and it will stay engaged until the driver backs off the throttle which
you can see, there.
Setting up that boost control strategy is actually a little bit tricky in the way we've
done this because there's a bit going on.
On the back of the steering wheel we have an Ecumaster CAN switchpad and all of our
switches as well as the rotary knobs on the steering wheel are wired up to that CAN
switchpad.
Now this allows all of the signals from those switches and knobs to be sent to
all of the other electronics in the car via a CAN template or CAN messenger I should say.
Couple of advantages here, first of all that CAN switchpad is incredibly small and
that's handy because there's not a lot of real estate on the back of the steering wheel.
Also we only need to run four wires from the car through to the steering wheel which is
12 volts ground CAN high and CAN low so that simplifies our wiring.
A nice feature when we are using CAN messages is that this is an industry standard protocol
so it doesn't matter whether you're using a MoTeC, a Haltech, a Link or an Ecumaster,
as long as you know the CAN template or messaging template, you can set it up to
send and receive to all of these different components.
In this way, what we've got is that Ecumaster CAN switchpad is sending out all of the
messages, it's actually being received into the MoTeC C125 dash.
The reason we're doing this is that then I can set up a strategy where we're taking throttle
position into account as well so that the driver doesn't actually need to hold that switch down.
From here, the C1125 then displays that party time message when the button is pressed so
the driver knows that they're at that high boost setting and it then sends out an
appropriate CAN signal to the M150 ECU to disable the boost limit and run that
higher boost pressure.
Functionality like this just gives us a lot of flexibility around the torque management
of the engine and particularly for example if we get to the racetrack and it's raining or
it starts raining during a race, this will allow us to dial back the power or dial up the power
as we see fit in order to be competitive while managing the amount of stress and strain
on the engine.
So all things considered I'd say that the tuning was a relatively smooth process
and pretty much a huge success baring our one small issue which was the missing seat
in the wastegate.
And keep that one in mind because you may be surprised how often this happens,
if you're facing an issue where you just can't get the boost response that you know a
turbo should be capable of, that is definitely one place to start looking.
From here, we've got a lot of work left to do before we can get to the first round
so I'm going to get back to it.
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