Mr Wijesinghe,
4DR5 engine produce about 75 to 80 HP on normal running speed.
I don't think that will be a burden on the 4DR5 Engine.
I will not agree on the above point...Coz i personely use BJ43 Which has a engine of 3B..I still feel when im speeding the difference with A?C & without A/C & the reading of the engine heat meter... Coz i have fixed manual meter as well....& when im driving My cousins j24..it clearly shows the extra burden on engine than normal condition.
but Machang,
Nothing to worry about that..Use 17C A/c compressor,
Don't use mac foil to cover the engine romm from inside...Hard rubber sheet ....is much more useful...