View single post by Judson Manning
 Posted: 12-30-2006 05:36 pm
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Judson Manning



Joined: 03-14-2005
Location: Atlanta, Georgia USA
Posts: 406
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 The 'D' cam has about .010" more lift than the US 'C' cam and 270^ duration vs. 272^ duration.  It is denoted by a single groove around the nose of the cam.  The 'E' cam has 260^ duration and is denoted by a double groove around the nose of the cam.  Both cams were supposedly found only in European 907 equipped cars (i.e. Elite).

The 107 cam (252^ duration) was the natural progression from the 'D' and 'E' cams.  Lotus realized the engine didn't need as much duration as originally thought (especially on the exhaust).  They did find, however, that the intake could utilize more duration, hence the 104/107 cam combo in the Excel SE.

The 104/104 combo is essentially the same as the stock 'C' cam, with more lift to accommodate the 2.2 engines.  On dyno plots the 104/107 produces the same amount of HP as the 104/104 but about 1000rpm lower in the rev-range.