Reply to "Hot air pockets?"

Assuming your coolant system is relatively stock...

Raise the rear end of the car while you fill the coolant system with coolant, unplug any bleeds you have on the top of the radiator tank(s). Slide the HVAC temp control in the interior to "hot" to open the heater valve and hopefully purge air from the heater core. Once coolant starts to flow through the bleeds in the radiator tank(s) you can re-install the bleed plugs. Once its filled to the top of the swirl tank start the motor, the cooling fans should be operating now to prevent overheating the engine. Allow the motor to idle for a while (rear end still jacked up) and keep adding coolant until warm coolant starts to over flow the swirl tank (this indicates the thermostat has opened), then intall the radiator cap. Continue running the engine, rear end still on jacks, for 10 minutes after it reaches operating temp. That'll help air in the radiator & tubes migrate towards the engine & swirl tank.

I've gone so far as to fill the car the first time with the thermostat removed, but I don't know if that is really necessary.

With the rear of the car elevated , there is no way to avoid air being trapped in the rear of the engine block and heads. So now you'll lower the rear and do something about the air trapped in the motor.

Shut the motor off, lower the rear end, jack the front end up rather high, restart the motor and let it run in this position for 10 minutes. Dont jack the front end so high that you loose oil pressure by the way. Raising the front end helps air in the engine block migrate out through the thermostat housing. Shut the motor off, lower the front end, let it cool down, remove the radiator cap, and top off the swirl tank.

Its a good idea to keep an eye on the level of the spare coolant in the catch tank after the first few drives in the car, you can expect the level to go down as more air is purged during driving, and replaced by drawing coolant from the catch tank during the first few cool downs.

When mixing your own coolant, premix the coolant and water in a spare 1 gallon jug, using distilled water from the grocery store, or water from a properly operating reverse osmosis system. The normal mix ratio is 50/50. Red Line water wetter is some good stuff to add to your coolant system, I've heard good reports over the years from people who use it. I use a similar product called RM25, purchased at a diesel truck service center.

George