Originally Posted by shlammed
Did you ever get these and check them out?
Yes I have one for testing, and learned that their selection is a bit tall for stock cams. If you reduce the base circle in cams by 0.040", the lifter needed would fall to midway of Ford lifter selection, giving plenty of selection to each direction for individual seat/valve/cam variance.
This is based on having +1 supertech valves, rebuild head and stock -01 cams.
I ended up getting Mazdasport shim under bucket lifters, height measured 0.6129" and 0.040" valvecaps from Manley, because I ran out of time to get new cams and Zetec lifters. The Supertech valves were individually shortened (max 0.012") to get the lash to 0.008 intake and 0.012" exhaust.
I did not feel comfortable shortening valves 0.040" or more to get the Zetec lifters work with stock cams.
Stock lifter with shim weight 47.1 grams while Zetec 32.6 grams, and the quality appears to be better than Mazda. Fitment is good if there is enough length between cam and seat for the valve to be.
Attached photos of stock lifter and Zetec in comparison.
Hope this helps.