Re: Performance mods - biggest bang for the bolt on buck

[christian147@domain.elided]

Now days most hot cams lift the valve well beyond the point of max flow. 
They do this to reduce acceleration and jerk (first derivative of
acceleration).  They have to get the valve open fast but continue to lift
at a lower rate to slow the valve before it starts to close.  I believe
the general switch to 45 deg valve seats is also related as the poorer
low lift flow will allow early opening and later closing so the valve can
be moved  slower.

Chris Hall
....
>    I feel lift generally affects a broad portion of the power band
>while overlap affects mostly high end.
>    as an example the TS uses an 11 mm lift cams for the street while 25
>years ago anything with that much lift would have been a wild race cam
>and also have lots of duration. better ramp design and valve spring
>metallurgy enable this trend.
>    as always, if i'm wrong, please correct me.

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