Cam Ratio v Failure Rate
Thread Starter
Pro
Joined: Sep 2004
Posts: 579
Likes: 0
From: North Texas
This has become interesting.
IMO the highest point of stress/failure would be:
cam lobe vs lifter
velocity of valve closure vs seat
A less agressive lobe OR a lower ratio rocker would affect the overall benchmark. That could be decieving. With a 1.4 rocker you would still have the "edgy" lobe but the overall benchmark would look safer. Instead of decreasing your rocker ratio, these vendors are recommending roller rockers. The theory behind this is to decrease stress in the upper valve train....
IMO the highest point of stress/failure would be:
cam lobe vs lifter
velocity of valve closure vs seat
A less agressive lobe OR a lower ratio rocker would affect the overall benchmark. That could be decieving. With a 1.4 rocker you would still have the "edgy" lobe but the overall benchmark would look safer. Instead of decreasing your rocker ratio, these vendors are recommending roller rockers. The theory behind this is to decrease stress in the upper valve train....
Melting Slicks
Joined: Jul 2000
Posts: 2,112
Likes: 2
From: Peoria IL
It makes sense to me if it only looks at on the cam specs as well. Higher ratio rockers increase effective duration at the valve, but can do nothing to the duration already ground in the cam.
