-> CH> ->The cam is a copy of the old L79 cam, other than what looks like
-> CH> a bit too ->much duration (222{at}.050 or 290 advertised), the lift
-> CH> is a paltry .447"

-> CH> The trend these days is more to shorter duration and higher lift,
-> CH> with a computer-designed constant acceleration parabolic curve.

->Hmm, slightly higher acceleration can be used where the valve is more open
->as the spring pushes harder when compressed...

It's more complicated than the simple "constant acceleration" term I
used.  They are concerned with not having the valve train components
exceed certain strain limits, yet maximizing the area "under the curve".

Other factors are harmonics and vibration at specific RPM ranges.  All
of this is far more important in racing engines than in street-driven
engines.  What is called "valve float" is often nothing more than the
valve springs reaching a resonant frequency where they lose the ability
to keep the valve seated.

One very interesting project is to take an old engine such as a flathead
Ford and outfit it with all the latest technology.  Flow bench porting,
computer designed cam profiles, electronic fuel injection, dual or even
triple spark plugs.  Then put it in front of a modern close ratio five
or six speed transmission.  The performance is quite remarkable.

It would be a fairly simple project to grab all the fuel and ignition
management stuff of a Honda and retrofit it to an old tractor.  Probably
drive the purists around the bend, but it'd be fun to see how it worked.

-c-

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