Tyre warmers for sure.... unless you want to cut a couple of warm up laps before a race. tyre warmers make a huge difference...
I would either leave the tyre warmers on the car for the entire race duration at a low temp like 30 deg... or I'd hit them about 1 or 2 mins before a race at 40-50 deg... then race.
keeping the warmers on for the entire meet is ideal as it keeps the tyres stable, having them warm up and cool down too much is what really wears them out fast...
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