A> Richard Konnen wrote:

 Paul,
  So if I understand the variable intake chart, you want the RPM to be at
max torque point and with the variable intake you can adjust for the
efficiency? If your shooting for max torque at 6K then why is max HP so
important? Such that it shows your making 600+ HP at 9Kbut the torque goes
away after 6K, so is the extra HP useful after that point. This is also why
I never undrstood  why drag racers would wind these engines up to 10 or 11K
if their torque peak was at 6 or 7K.
Tanks,
Richard Konnen

A> Max efficiency occurs at max torque all other things being equal.

A> Torque and RPM are related. Max torque at 6000 RPM is also max
A> HP at 6000 RPM. In the automotive world this is foreign to
A> conventional thinking as they would like max torque at the lowest
A> possible RPM with the max HP at say 6000 RPM.

A> Here is the simple formula  HP = RPM X torque / 5252

>From this RX8 torque curve you can calculate and plot the HP

A> curve. One Newton/Meter equals .737 foot pounds.

A> Acceleration has nothing to do with torque per se.
A> All it has to do with is HP to weight ratio.

A> Force = Mass times Acceleration.

A> Acceleration = Force divided by Mass

A> The amount of force you can get and any speed is proportional
A> to the amount of HP you have at that speed.

A> The same goes for airplanes. Airplane fly on HP and not
A> torque.

A> The rest is gearing.

A> This will take a bit of thinking out side the box
A> for most automotive types as we tend to acquire an
A> emotional belief system. We think we know something to be true
A> for a very long time and this causes our brains to block
A> any new way of looking at the subject. I have no answer
A> for this except to try and forget everything you think you
A> know about the subject and start over from the very basic
A> fundamentals :)

A> Vance, do you have an electronic copy of that article you
A> wrote on this subject for alternative engines? I would like to have
A> it and republish it here from time to time. I can OCR it too
A> if you can loan me a printed copy.

A> Paul Lamar

Well Paul I will take my hat of to you as you have explained the
relationship perfect. My son has just finished Uni last year and we
had many conversation over this subject where he was talking to his
lecturer and trying to understand.
It took me many diesel engine dyno sheets to show how it works, these
dyno sheet show the relationship well and I will post one to help all.
As you say max torque is the most efficient RPM of the engine. Both hp
and torque rise with rpm but not at the same proportions relative to
rpm.

--
Best regards,
 ddunbar                            mailto:ddunbar@echidna.id.au

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