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Reply to "From Sea Level to 10,023 ft"

Your guess is better than mine, @ALB. I went to EFI after my kadrons told me that 5000 ft didn't agree with them. There are some real jetting wizards here and I'm not one of them.

To answer your correction question, I was always leaning out the fueling as we gained altitude. In this case, it took more throttle to fill a cylinder with a certain volume of air since the air pressure was lower. Without Baro correction the ECU looks at the throttle position and sends more fuel than matches the air in the cylinder.

The Alpha-n setup sends the matching volume of fuel based on where you set your ideal tune. I spend 90% of my driving at sea level so that's where I set my base tune. I've got a table of throttle positions and rpms that's filled with my desired air:fuel ratios (Target AFR). After getting a rough tune (you turn the TunerStudio Autotune on), the laptop will adjust your fueling map so it's close to your AFR targets.

You then just datalog your driving for a few days and use a finer grained program (MegaLogViewer - MLV) under lots of driving conditions (low speed, full throttle runs through the gears, highway cruising, etc). MLV will take the log files, exclude whatever you want (records below a certain temp, rpm range, etc) and give you a revised tune based on your AFR targets.

Rinse and repeat making the changes smaller and smaller (you can set it Easy to change, Normal, Hard, and Extra Hard to change). At the end, you've got a 95% good tune that you can do minor tweaks to.

So, I'd done that already at seal level and liked the tune. I could then just head up the mountain and tell the Baro table the percentage of fuel I wanted it to take out of the known good fuel table.

I know it's complicated, but not having to take the tops off of the kadrons and finagle the jets at the bottom of the bowl is rewarding.

Sharing your AFR targets feels a little like telling what oil you use, but here's what I like for how I use the car. RPM is at the bottom and % throttle on the left.Screenshot_20220518-184400

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Last edited by Michael Pickett
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