"John F. Kelly Jr." wrote:
>
> -------------------- Begin Original Message --------------------
>
> Message text written by INTERNET:mrc01@flash.net
>
> "Torque may give some guys hard-ons, but it doesn't by itself make
> the car go fast. For that you need power.
> "
> -------------------- End Original Message --------------------
>
> The more torque you can design into an engine at 2000-2300 rpm, the quicker
> you will emerge out of an autocross turn.
On an autocross shifting gears slows you down so you want a flat
torque curve that allows you to use a single gear over a wide
range of speeds. But it doesn't matter how _much_ torque you
have, it's the _shape_ of the torque vs. RPM curve that matters.
If two engines have the same horsepower, all else being equal,
the one with the flattest torque curve will win the race -- even
though this may be the one with less actual torque. With a
flatter torque curve you'll spend less time shifting gears.
In a straight line drag race it's power that matters and with
good gearing you can toss torque and the shape of the torque
curve out the window.
Speaking of engine design -- my last racing motorcycle had a bore
of 80 mm, a stroke of 44 mm, torque 50 ft. lbs. and power 115
horsepower. On that machine, 12,000 RPM was magic! Zero to sixty
came up in about 2.8 seconds.
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