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How does the spark table & VVT Intake (Relative Timing) Table Interact?

Old May 31, 2019 | 07:18 PM
  #1  
HowPrayGame's Avatar
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Default How does the spark table & VVT Intake (Relative Timing) Table Interact?

Sanity Check

I have been searching around and can't find a clarification on how these tables interact, my understanding is that the car knows (somehow) how far to advance or retard the intake cam, and the value within the VVT Table is the maximum amount of degrees it can add to the spark table. Is this assumption correct?

For example, on these tables, at 6,000 RPM, the 27.4 degrees at 86 kPA would have 9 degrees added to it, making the timing 36.4

I am planning on modifying the timing table slightly in the cruise regions and on higher load regions for my car which will be staying N/A for a few years. If this is how the graph works, would I need to change the VVT table timing when adding timing to the spark table, so the car doesn't advance the timing too much and cause detonation?

Here is the spark/VVT map off my MS3 Basic Basemap for reference



I was planning on just ripping the spark table, AFR Target Table, and VVT Timing Table from Brains basemap as his timing seems much more aggressive than my current table, just to see how the car responds, and put together some detcans to listen for detonation. My current fuel economy is extremely poor as my current target table is super rich in the name of safety. How terrible of an idea is this?

I was also looking at DIYAutoTunes basemap and their timing numbers are even more aggressive than Brains map, both the VVT Timing and Timing Tables, unless there is another table potentially adding/pulling spark I am not accounting for
Old Jun 1, 2019 | 08:51 AM
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I *think* you might be overthinking this.

Spark table is in crank degrees so it doesn't matter what the cam is doing.
Old Jun 1, 2019 | 09:28 AM
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Originally Posted by HowPrayGame
I was also looking at DIYAutoTunes basemap and their timing numbers are even more aggressive than Brains map, both the VVT Timing and Timing Tables, unless there is another table potentially adding/pulling spark I am not accounting for
I read from a few people here a while back that DIY's 01-05 basemap is not very good. People were reporting knock from the base ignition table. There were other miscellaneous settings that were a little funky as well. I'd link it but I don't remember where I read it. It was a pretty random thread.
Old Jun 1, 2019 | 10:12 AM
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The Ignition table(s) and the VVT Intake table are not related and do not interact.
Old Jun 1, 2019 | 12:46 PM
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I completely misinterpreted the two tables, the valve opening/closing time doesn't add or subtract anything to the spark table. I was definitely overthinking this one, I will play a bit with the spark tables, try out Brains probably. I did read about DIYAutotunes map detonating and that doesn't sound like something I would be interested in trying.
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