Measuring a set of lifters I just pulled out of an engine they are .4365" is and fit the lifter biores well. I have a new set from one of the vendors that measure .4375" OD. The new ones are too tight in the bows; they are an interference fit.
What's going on here?
I would say you have a block with no ware at all.
Original build specs are,
Push rods .4355-4365"
Push rod guide holes, .437"
Thanks Frank. The original lifters look like new. I may use them with a new Stipe cam rather than ream out the lifter bores.
Seems like I've seen oversize lifters advertised. Even if that's not what you ordered, maybe it's what you got.
No, the "standard size" lifters are advertised as being .437" - and they are.
I continue to be amazed at the quality of original Ford parts.