Re: [Amc-list] Super Long Intake Duration Cam ???

[David Crooks <david.crooks@xxxxxxxxxxxx>]

" From: David Crooks <david.crooks@xxxxxxxxxxxx>
" The relationships between cam timing, duration, and rpm are reasonably
" well understood, and the cold fact is that there is no one grind
" that's best for both low rpm and high rpm operation.  That's the whole
" reason that modern high performance motors are using variable timing
" on the intake and exhaust cams.   Reduce the compromise, for the best
" of both ranges...
 From Andrew Hay
i wouldn't be surprised if one wouldn't want 2-dimensional control for
peak efficiency, both speed and throttle as inputs to valve timing.
narrow timing would be better at less than full throttle at any rpm.
________________________________________________________________________

Actually you are 100% correct, and it is done that way.  In the
case of the high end BMW's, there's no butterfly valve in the
air intake any longer.  All throttle control is done by adjusting
the cam timing and lift, electronically.  Do a little surfing, and
you'll see that totally camless engines are being developed,
to allow total and complete flexibility.

Cheers,  Dave
-------------- next part --------------
An HTML attachment was scrubbed...
URL: http://splatter.wps.com/pipermail/amc-list/attachments/20081119/0baa50f2/attachment.htm 
_______________________________________________
Amc-list mailing list
Amc-list@xxxxxxxxxxxx
http://splatter.wps.com/cgi-bin/mailman/listinfo/amc-list