X-Mozilla-Keys:                                                                                 
grobbins wrote:

I have no data to back this up, but I know engines that are dynamically tuned
(and non-adjustable) tend to have a peaky torque curve. Wouldn't an
un-dynamically tuned torque curve be flatter and better? When you add a
turbocharger and wastegate, aren't the beneficial effects of dynamic tuning
blown out the gate if max boost is achieved before the dynamic tuning range?
Just seems that the flatter curve boosted to higher levels by the turbo would
be more desirable.  Am I missing something? You don't cruise at 6000 RPM do
you?
Grant

It is a question of volumetric efficiency. In the first place airplanes
don't really need wide torque curves. The volmetric eff is increased
at the desired cruise RPM by tuning the intake runners.
Sure you can get the same power by upping the boost but you pay for it
in increased back pressure hence more fuel.
If you have room tune it.

Paul Lamar
 
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