Optare

[126th street]

RE: Optare
You will tend to find the heating capabilities of more modern buses to be vastly superior to older kit such as Scanias, Atlanteans and so forth as the small engines they features are working very hard and generate plenty of waste heat just as a car engine would under such circumstances.

With the older kit something like an 11- or 12-litre motor, when they were fitted, were often designed for hauling around 40tonnes of articulated truck and were thus derated for bus use to improve engine life in a sector which by design features regular, brief periods of full power followed by similar times of idling. They thus generates little waste heat as in many cases it could take a number of hours for them to even reach operational temperature in the first place. In particular Gardner and bigger Scania engines take absolutely forever to reach the c80 degrees C temperature.