00:00 |
- Now that we have our base run out of the way, we can get started into making our actual calibration changes.
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00:05 |
Provided there's nothing alarming in terms of EGT or lambda numbers that's shown up in our base run, you can go through some preliminary changes to the calibration.
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00:13 |
The general workflow I suggest can be applied to most diesel tuning jobs but the magnitude of these changes will need to be considered and adapted to suit your specific application.
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00:22 |
To start with, we want to address any torque tables and torque limits, making sure that these are realistic for our aims.
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00:28 |
We can make some assumptions at this stage but it's likely we need to come back to these once we've actually got some results from our tune, dial them in a little bit more accurately.
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00:37 |
It can also be a little tricky to correlate torque values in some of the maps with what we're reading on the dyno.
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00:42 |
Particularly as readings from each dyno will vary dyno to dyno.
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00:45 |
You can, however, look at percentage changes and apply them that way.
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00:48 |
What I mean here is that if you picked up 25% torque at 2000 RPM on your brand of dyno compared to your base run, you can take the factory torque figure and apply this same percentage increase.
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01:00 |
Next, we want to address our boost control and to start with I'd suggest making a small increase in the high load operating area of approximately 10%.
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01:08 |
In some applications, 10% can be quite conservative and there may be headroom to go further but we can test this when we begin optimising the tune.
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01:17 |
With our boost targets increased and adding additional airflow to the engine, we can now take advantage of that extra airflow by adding some more fuel.
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01:24 |
There is a three pronged approach to this and we want to address our fuel pressure, our fuel quantity and finally our injection timing as we've discussed in the relevant sections of the course.
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01:33 |
I'd suggest starting with a relatively modest change in fuel delivery of approximately 10% so we can assess the effects before optimising further.
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01:40 |
A 10% change is also quite conservative and when matched with a small boost increase we should be maintaining a safe air/fuel ratio, not creating excessive exhaust gas temperatures.
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01:49 |
We can now make appropriate changes to our injection timing.
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01:52 |
This is easiest to do using a timing calculator spreadsheet.
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01:55 |
I'd suggest starting with a 50% target to get up and running, this can then be tested and optimised further in our next step.
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02:01 |
At this point, we should have a good starting point for our calibration that on its own should yield a reasonable gain in performance while not putting the engine at risk.
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02:09 |
We can now flash this calibration into our ECU before moving onto the next step.
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