Question!

[Qhergt]

Been looking at building one.
However I'd like to re do the display. It would be nice to have the CHT and EGT separate from eachother. Also, I think it won't take much to include Alt, VSI and ASI into this.

[tomcourt]

Display layout is pretty flexible. So CHT/EGT is certainly possible.

Altitude is a bit tricky. Requires a pretty accurate absolute pressure sensor. As well as a fair bit of math (remember there isn't room on board the Leonardo to do any floating point math and all the other stuff I'm doing) and a pressure adjustment control. For a minimal panel you may want to try and get by with just GPS altitude (not sure the legalities here).

For airspeed indicator you may want to consider the hazard of a frozen display. I've got javascript to clear the display after several seconds of no update but I'm not sure if I'd trust it for ASI. For engine gauges there is a fair amount of time between something not being right and a true hazard, for ASI it can be a lot less.