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Old 08-09-2019, 06:46 AM   #377 (permalink)
Ecky
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Join Date: Dec 2011
Location: New Zealand
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ND Miata - '15 Mazda MX-5 Special Package
90 day: 42.54 mpg (US)
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Small update: Haven't been working on my car nearly as much as I want to. I bought a house in February and over the last month or so tore an entire side of it off, down to the studs, to replace insulation, sheathing, windows, wrap and siding. Parts of this are time-sensitive and need to be completed during periods where I have both some time off work and a few clear and dry days.

As for the car, I managed to spoof the ECT to stay right in the middle (haven't yet figured out how to properly make it move), took it in for Vermont's very strict state inspection, and had it pass.

I also have been tweaking my fuel maps further on my drive to and from work. I was having an issue where in the mornings it was biased rich, and in the evenings it was biased lean. What I eventually came up with was that intake air temperature was different, and differences in both temperature of the engine and air were able to swing the fuel tables as much as 5-7% in either direction. So, I'm playing with different curves and re-tuning the fuel tables. I don't think the difference observed in the fuel maps is as large as the raw difference in air density, and the difference at low load is different than at high load, plus I have to sort out how much enrichment needs to happen from having cold intake runners and cylinder walls. At those cam openings with a lot of hot EGR happening, the cold coolant enrichment needed is much less. Turns out there's a lot of fine tuning for internal combustion engines, go figure.

Last edited by Ecky; 08-09-2019 at 08:07 AM..
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