I used to leave my track car at home too many times as it was hot and with race harnesses on a low ventilation it was easier to drive something else and be in comfort.
This is one of the reasons that I fitted things like heated seats to my Cossie pug so that I could happily use it in winter. I also fitted the std blower / heater as it was roasting without the fan. I am looking for a roof vent too.