[Fot] A cam for Rick

[Rick Parent]

I just looked at the cam list wow, somebody has spent some time amassing all that data, very cool.
The BFE 24 cam at the bottom of the page is a monster according to the seat duration alone. In my experience a 327 seat duration is for a super high revving engine like +10,000rpm and probably starts pulling around 7-8000rpm, its way to large for any Triumph motor. Off the top of my head a 6000rpm motor should have a seat duration of around 280ish. Too large of a cam is way worse that too small of a cam. Too large a cam will not pull at lower rpms, too small a cam will stop making power at a certain point but will generally keep making that same power all the way to the end of your parts combo will allow it to go before the power drops off.
Always keep in mind, time is a critical factor for the inlet charge, the higher the rpm's the more duration or time is necessary to charge the cylinder.
Rick Parent
"Doing the right thing is always the right thing, regardless of consequences"
 

    On Sunday, January 22, 2023 at 11:29:54 AM MST, Larry Young via Fot <fot at autox.team.net> wrote:  
 
  The numbers for Erson/BFE #24 mentioned by David and Henry is the last one in my list and has the longest duration. Like Henry said, if you drop below 4,000 your dead.
 
 I got interested in the history of cam design. According the Speedy Bill Smith (Speedway Motors) the real innovators after WWII were Ed Winfield and Collins of Harmon-Collins (see the book "Souping the Stock Engine). He said their designs were heavily copied by the others. I think Kas's cams were designed by someone from Harmon-Collins.
 
 I certainly don't have the experience of many others on this list, but I'll contribute a few comments on what Rick has said. Cams is a subject that is mysterious (Rick said "black art") to many, so it is easy for them to be fooled. There is nothing mysterious about it. I agree that most people put to much emphasis on peak HP rather than the entire range you will operate in.
  - Larry 
 
 
 On 1/22/2023 6:46 AM, David Gott via Fot wrote:
 
 
 Hi FOT, 
  I used Larry Young’s site to learn a lot about cams and their relative effects on engine performance with some crude engine modeling software, in the quest to pick the right cam for my wants, building a strong mid range engine, trying not to spin over 6,000 if I can help it with a stock based crank.    Does anyone happen to have the specs on the Gillander’s #24 they could share?  Just curious.  Maybe it’s at the pointy end of the list below? 
  Rick McCurdy, here’s the cam reference list Larry put together, below, and I’d sure be curious what Rick Parent’s software would say I should have done!!!   
  Triumph Cams  
  
 
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