Picked up the car from respray and want to get it as clean as possible for EDC and Time Attack show at Silverstone on 1 June where we have a club stand. There is a lot of dust etc under the bonnet, The engine's an NA and not dressed yet, just stock but clean, am also polishing engine compartment prior to the weekend - question is, is it advisable to spray wash the engine. I can remember some time ago in Germany garages using a mixture of gunk and petrol as a pre wash spray which left a gleaming finish, anyone used something similar? Not afraid of hard work and have Meguires metal polish to finish off.