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Nevermind I found the kit in the Hot Deals section.

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Cool! I do have my own rocker design in the works. I'll have them on my website as soon as they are available. In the meantime, I carry some budget rockers that work very well for most applications, when used with my kit.

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So ( on a smallblock) the rocker sweep the biggest loss in efficiency? I would think minimizing the arc between the pushrod and the rocker stud would do more overall to improve the net lift than the sweep over the valve. The fulcrum ratio ( c/l of the rocker shaft to the cl of the roller vs the net lift of the stud is fixed, but the net motion is effected by the sum of the losses from the lobe itself to the rocker body. Big losses just in the loss from the 59 degree poly geometry inherent in the Shortblock. The pushrods also move in an arc on both ends. With a good long guide in not really as concerned with roller sweep ( after all it is a roller) as I am with the sum of all the other lost motion issues in the valvetrain.!lets not even think about the losses from the pushrods lateral angle with an offset rocker like a W2.

So I guess to target the net lift and duration you need for optimum performance it's probably smarter add lift compensation to the lobe so you 'net' the desired lift.

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Wize, I'm glad I've got you thinking. I know what your saying about the pushrod side, but the lost motion there can be made up with a properly designed rocker. You mentioned the loss of net lift. Where is the measurement taken, full lift? What about at every 10 crankshaft degrees? Most people check full lift for losses, but nowhere else, so they miss the losses through the lift cycle. Minimizing the pushrod losses won't help gain that back.
Also, it's not just about net losses. When the valve side is off, the velocities of the cam lobe are occurring at the wrong place causing serious valvetrain instability, and that destroys parts.
On more thing to note, when using an offset rocker, such as a W2, the pushrod angle becomes compounded, so out really doesn't increase as much as one might think. The angle is in a straight line, even though it is in two axes.

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Good topic. Need to get Vic Bloomer in on this topic. He's studied the lobe to rocker geometry closer than anyone I know. I can see any way you can minimize the losses to the fulcrum point will naturally get a higher percentage of the lobes motion transferred to the lift side of the see-saw.

But it's hard for me to visualize how you can truly 'make-up' for the sum of those losses with the rocker itself ( without over-compensation ( ex: use a 1.6:1 'gross' just to 'net 1.5) ....and even then the 'degree by degree' motion of the lobe won't/can't be 'linear' even if the lobe to rocker were close to perfectly straight.

And in a way the factory stamped rockers allow the pushrods to move straighter in their range of motion up top....because the 'slop' in the factory rocker on the shaft allows the rocker to slide ( with some obvious 'slop') in lieu of the pushrod oscillating as it must in a tight clearence aftermarket rocker.

I always looked at some degree that valvetrain lost motion as kind of a 'necessary evil' present in any cam-in-block motor.

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