Hoosier Hurricane (2/5/2008)
Ted: Do you remember the Shaller 1/4 speed camshafts of the '60s? Dual lobe, as you depicted. They were roller tappet cams, and gear driven. They had to do that to keep the size of the top gear small enough to fit inside the timing cover. Included was a distributor with a built in planetary gear setup to speed it and the oil pump back up to 1/2 crankshaft speed. They were short-lived, either to expensive to produce competitively, or were never accepted by the rodders.John. I did remember someone actually doing this cam design but didn’t have a name to put with it. Thanks for the name and the details on the ignition and oiling.
Cactus (2/5/2008)
This thread has addressed the imbalance in the cam, and I think, started with the counterweight to balance the fuel pump eccentric. What happens if you don't install the eccentric to start with?Even with nothing but the cam gear in place and the eccentric removed on the Y camshaft, there is still an amount of imbalance present. As John brought up earlier, this has to do with the stacking of the lobes at the front of the camshaft due to the firing order. This is not unique to just the Y as almost all engines exhibit this to some degree on one end of the camshaft or the other. The Y Block when first introduced was one of the few efforts made to address this before being dropped as an item that didn’t justify the cost in doing it.
I’m simply balancing the camshafts because I can. And it's cheap on my end. Worth the effort? Undoubtedly not on a driver but in a performance application, I’m just going for anything that can have a potential benefit whether it's a measurable gain or not.
Lorena, Texas (South of Waco)