Yes, cold air charge with higher cylinder temps. That's why you need a true cold air Intake, or somewhat to cool the intake charge. I know it may sound crazy, but you can have a cold intake charge and an engine running 200 degrees coolant temp. At full throttle, there isn't a lot of heat soak getting into the air, I mess your intake is restrictive.
There is also a point where more timing doesn't produce more hp. The Hemi is at about ,28-30 degrees of timing , any more than that and you aren't gaining anything but engine heat. And you can safely run 28 degrees of timing, on 91 octane, with a max power tune, and 210-220 degree engine temps.
As far as your Stingray, you are some sort of an outlier if your engine truly runs that cold from the factory. And that doesn't mean it's good.