I just installed my first ever CHT, a Dakota Digital.
I understand each car may be different but I am looking for some ballpark figures.
I read that the gauge has an internal heater to compensate for the cold junction so my question is this, how rapidly will the reading climb? Does it hit 200 fast then head temps rise slowly or do the heads hit operating temps quick? One minute, five minutes?
Ballpark what is the temp range that is OK for the heads?
Trying to understand what I will be looking at.
After seeing the driver side flap pop into closed when it should be open during a build once I am always paranoid.
Thanks
DJ

I’ve got one, it works great. Shows ambient temperature when I turn the key to start.

300-325F is perfect full hot temp (30 minutes, 3000+rpm), 350F is okay for short periods like pulling a long hill, 375 is way too hot (heatsoak) and 400F the aluminium starts to get soft.

Once you have a CHT you'll see just how bad lugging or leaning out an aircooled engine is.

Mine does as well. I'm not sure what the question is, but my gauge shows ambient and then climbs somewhat slowly to operating temp on the head side. For the sake of example, let's say it takes about 5 minutes for the reading to show 200+ degrees. I've also got a temp sensor in the stock CHT location (for Microsquirt), and that lags significantly behind the DD sensor. Eventually (e.g., after about 10 min) they basically even out and show roughly the same temp.

If you've never had a head temp gauge you'll see how much temps can fluctuate going up and down hills, during overrun, etc.

I think Mark's numbers are the conventional wisdom for a stock setup. My last two type 4's with ceramic coated heads and Raby cams didn't get about 300 very often.

Thank you for the information Gentlemen. I stand on the shoulders of those that have gone before.
On the few quick jaunts I have taken I am getting Stoic readings of about 14.2 at idle, 13.6 cruising (have not been on highway yet) and into the 12s at Wide Open. I have not had any long runs, I was waiting for the CHT, so information is minimal right now.
I am about to give her a go.
Wish me luck.