When my thermostat was stuck open it would take me 30 mins of driving to get actual heat. After I fixed it still takes ages for most (small) cars to warm up at

When my thermostat was stuck open it would take me 30 mins of driving to get actual heat. After I fixed it still takes ages for most (small) cars to warm up at idle. It's only when you start driving excess heat is produced. Same with a boat oil changes - you either sit there for half an hour and maybe oil loosens up or you go for 15 minute spin around and it's ready for sucky sucky time.