87 degrees celsius is the standard opening point for most thermostats for that car, it sounds like the temp is close to normal. If the temp goes up at idle it is an airflow issue if there is an issue, if the temp goes up while on the highway with the air rushing through it is radiator related.

If you are in traffic and the heat is climbing too high get moving as soon as you can; but, in the interim turn the heater on full blast.

What ratio of coolant to water did you use? 50/50 or 1:1 is the most coolant that should be used. Coolant is not a good heat exchanger, water is better but some coolant, at least a 1/3 is needed.

RedLine WaterWetter is an emulsifier that works, I've used it.

If you do a flush/cleaning use CRC ThermoCure, great stuff.

Sent you a PM.

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