But you would need to size vents for full throttle anyway ....
I think we are all guessing so far ....

I'd have thought a "gas" ( petrol in this part of the world ) engine might
have been less forgiving of pressure drop through the vents. Or it might be
something to do with cooling?
David


"Steve Barker" wrote in message
...
It has nothing to do with compression ratio actually. The amount of air
is
increased because a diesel has no throttle blade nor is any measurable
amount of manifold vacuum created. A diesel of say 400 cubic inches uses
the same air a gas engine of 400 cubic inches would if it were run wide
open
100% of the time.

--
Steve
=======================
Remove the not dot from my address to abuse my email box
"L & D milligan" wrote in message
...

"Jacques Mertens" wrote in message
...
It would not be sufficient for a gas engine but diesels need twice the
air
of a gas engine.
If the two engines are of equal capacity and turning at the same speed
and
both are say four stroke engines then why would diesel require twice the
amount of air?