On Fri, 14 Aug 2009 12:56:11 +0100, R C Nesbit > wrote:

>Yes, but under no load the noise only comes in at high revs, so is
>competing with the engine noise.

The reason for that is that it's a clever variable venturi turbo. This
allows the ecu to control boost pressure depending on engine speed and
load rather than just due to exhaust pressure (to a certain degree).
Just revving the engine won't put much load on so the turbo won't get
to deliver its maximum charge.

If you go flat on the accelerator, the rule book is often thrown away
by car engines and they will care little for perfect fuel/air ratios
and emissions. They'll just attempt to max out as best they can.

--
Z
Scotland
Alfa Romeo 156 2.4JTD Veloce Leather
'Oil' be seeing you..
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