Spot-facing for 39gr. lifters

[yetibone]

The cups look long enough to sustain a long range of motion for a high lift cam, but I see what Jake is saying about the oiling issue. Only at full lift does the cups get oil, and ONLY if the bushings are lined up with the oil galleries properly (i.e. correct depth). The oil gallery opening inside the stock lifter bores on a Type IV are very large, and give the bushings a good range of placement, dependant on the cam's lift. The cam's lift would also dictate how deep to spot-face the stock lifter bores.

The higher the lift, the deeper the bushing would have to be placed, not to exceed a depth in which each cup's oiling groove would never reach it's gallery opening.

I've never seen the older version of these lifters except for in pictures on this website, and from what I saw in the pictures, the ones I have seem much improved over the old ones. The new ones seem longer, and have mo' better oiling provisions, but like I said, I've never laid eyes on the earlier 39gr lifters.

Looks like I've got some math homework to do...

Thanks for all the insights on this guys!


Yetibone