So wrong, sucker

Sir,

In his article on the GMC Blower (Technofile, October issue), Keith Howard perpetuates the myth that diesel engine superchargers and turbochargers suck instead of blowing as on petrol engines, which is very far from the truth.

The principle is exactly the same whether the engine is spark or compression ignition. Two-stroke diesels are unusual in that they only use blowers to scavenge their cylinders and ensure they are full of fresh air for the next cycle, not usually as a supercharger.

I am, Yours etc,

M. Blakey, Coundmoor,Shrewsbury