Quote:
What you are measuring is correct. The problem is that the lifter is not pushing straight on the pushrod. This was first brought to my attention a few years ago when Rob McC was designing LA rockers for Erson, and was wondering if he should make the true ratio of their 1.6 rockers something like 1.65, in order to get the valve to open exactly 1.6 times the lobe lift. He posted the question in a Moparts forum. I remember trying to figure out why that would be and finally came up with the idea that the actual lift at the top end of the pushrod is the lobe lift times the cosine of the angle between the lifter axis and the pushrod.
R.
basically cosign of 11 degrees times the gross lift...minus the lash...
then you have the true rocker ratio...which is ???
Tony
70 AARCuda Vitamin C
71 Dart Swinger 360 10.318 @ 128.22(10-04-14 Bakersfield)
71 Demon 360 10.666 @122.41 (01-29-17 @ Las Vegas)
71 Duster 408 (10.29 @ 127.86 3/16/19 Las Vegas)
| 
