As the dog was saying, water IS better at transferring heat than a mixture of water and coolant, and can allow lower operating temperatures in a situation where the cooling system is running at or near its capacity to remove heat (ie thermostat already full open). We run that 50% mix of ethylene glycol for two main reasons: 1. It keeps your block from freezing solid and cracking in the winter (probably not an issue in Miami), and it inhibits corrosion a whole lot better than plain water.

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Whoever said there's nothing more expensive than a cheap Mercedes never had a cheap Jaguar.

83 300D Turbo with manual conversion, early W126 vented front rotors and H4 headlights 400,xxx miles
08 Suzuki GSX-R600 M4 Slip-on 22,xxx miles
88 Jaguar XJS V12 94,xxx miles. Work in progress.