Quietest cam design?
03-01-2005, 10:48 PM
#21
Originally Posted by 02Reaper
Do you mind stating how? I have a futral cam in my truck. Here are the specs.
271* @ .006
221* @ .050
135* @ .200
221/221 .586 .586 112
Subtracting the .006 value from .050 is 50. An xer lobe is 49. A xe lobe is 53. Looks to be pretty much an xer lobe to me. I like my cam and yes it is noisy. But regardless of the grinder, whether it be cammotion, comp, crane, etc. There is no magic voodo to lobes. Either they are aggressive or not. Please explain.
271* @ .006
221* @ .050
135* @ .200
221/221 .586 .586 112
Subtracting the .006 value from .050 is 50. An xer lobe is 49. A xe lobe is 53. Looks to be pretty much an xer lobe to me. I like my cam and yes it is noisy. But regardless of the grinder, whether it be cammotion, comp, crane, etc. There is no magic voodo to lobes. Either they are aggressive or not. Please explain.
One of the best quotes that I have ever heard relating to this is one by David Reher "It's not the installed pressure that matters but the pressure over the nose." In the case of a XE-R lobe that very much the case.... The more you think about what he says there the more you get it. I'll add that the seated pressure is very important also.
Now as for the 221 @ .050 Futral/Cam Motion lobe....
Compare that too a similar XE-R lobe....
CM LIFT XE-R
271* @ .006 271*
221* @ .050 222*
135* @ .200 144*
.345 MAX LIFT .342
What sticks out the most to you there?
The .200 duration.... putting that much extra area into a lobe between .050 and .340 of lift is not really easy, and it's not easy on the parts either.
Think about that comment by Reher and you'll get why a Beehive likes the Futral/CM lobe and not the XE-R lobe.
This might be a little vauge, but leading a horse to water is one thing.... showing him how to drink the water is another.
Bret
