these lifter were done by a machine shop,engine builder
i had a stock set of lifters they made them a semi-solid

and what i mean is they took a stock set and change the inside spring and shimmed them so insead of having 80ths of collapse it only has 15ths. of collapse it help not to have valve float i have close to 400 in just the lifters i can't use them anymore so got to go

125.shipped

 

so these aren't compatible with a standard cam and spring setup?

 

yea with adj. rockers can't used them now cause the lift on my cam is over 700