Originally Posted by Buzzkill247

Plates with thermostatic have an extra "nub" on the backside with the thermostat valve is encased.
Plates without have a rounded back and just the input/output ports

As mentioned above, ALL thermostatic plates allow around 10% flow at all times to prevent air locking and cold shock in the rad.

Anything north of the Mason-Dixon line really should be using thermo plate. below that, not really needed (for all 3 days of the year it gets actually cold), just don't drive like a moron (keep throttle on roll and below 4k shitfting) until you hit at least 140 temp - and if you are driving before minimum 1-2 min warm up time... sell your Z now or start saving for a new engine later lol