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Setting up a base tune for an air cooled VW engine that uses Cylinder Head Temp (CHT) as an equivalent means of using "Coolant temp" for measuring engine temp on a water cooled engine.

I discover that a selection of tables that uses "Coolant" for the X-axis, have different Maximum values:
Max 250:
- Warmup Idle Multiplier
- Cranking Idle Air Multiplier
- Warmup fuel manual multiplier
- Warmup timing correction

Max 170:
- Cranking Coolant Temperature Multiplier

Max 120:
- Priming fuel pulse

I just did a quick search in TS for "CLT". There might be others...

Would it make sense to define all these as "250" to accommodate headroom for an extended aircooled "CLT" range?
Would another solution be to have an option that lets the user select "watercooled" / "Aircooled" and an upper limit for the CLT or CHT variable used globally in firmware & TS?

What's an actual upper limit you'd expect to see from CHT on an air cooled engine? 150? 200? 250?

The only air cooled I've dealt with were carbureted aero engines that I'm not sure even had real numbers on the CHT gauge (if they had one at all), so we're a bit in the dark here on what it "should" do to better support air cooled engines.

Highest I ever logged on my Bug was 175°C during a long mid-summer traffic jam.

Should have some headroom though, so I reccon a 250 limit should be fine. By the time you hit that level, I believe you're dealing with some more serious problems