The Stovebolt Site Forums The Shop Area Engine Shop valve lifters-height

Hi fellow stovebolters.
With the advise of a buddy I am replacing the valve lifters on my 250.
I went to 3 auto parts stores and each showed me lifters that are about 1/8th of an inch taller than my originals.(the body) The oil hole and groove on the side are also a little higher. Each store double checked the part number.
My buddy says this will throw everything off in the valve train.
I disagree as they are hydralic(spellcheck). As long as the plunger does not bottom out? After 0 lash some turn 3/4 turn some 1 turn. I also believe the oil galley is wide enough to feed the oil holes on the side of each unit. Maybe Napa, Auto Zone and Advance Auto each carry the wrong lifters for a 66-250? Are they the same as a small block?
Would love to hear opinions on this.
Will post another question in relation to this subject. Thanks for any advise.

Same as a small block Chevy.
http://no25.chuckthetruck.com/page2.html

Chuckthetruck is correct. My 250 took the same lifter, which for once, made them cheap. Unless you have other issues, you have plently of adjustment in the valve train. Could be someone else put shorter lifters in before.

Is there any reason to replace just the lifters, without changing the cam, too? If they're worn out, it's highly unlikely there's enough cam left to work right. Be sure to do the 20-minute break-in run at 1500 RPM or so before you let the engine idle, or you'll damage both the cam and the new lifters. It basically has to establish a new wear pattern, and the cam/lifter assembly needs to be flooded with splash oil off the crankshaft while that's happening.
Jerry

Thank-you for the advise. Since I bought the new lifters I guess I will go ahead and put them in.
I pulled the lifters from 1 cylinder and the cam looks fine, not pitted or anything unusual. Am going to pull all lifters to at least clean them and will check cam.
Do lifters actually wear out?

Yes, they do. The bottom of the lifter, where it contacts the cam lobe, should be slightly convex, higher in the middle than at the edges. This is very hard to see, unless you put a straightedge across the lifter. It should rock slightly, not show a totally flat bottom, or, worst-case, show a low center. The cam lobe is also ground slightly tapered, so the lifter spins as the cam lobe operates it. Once a lifter is worn flat, or cupped, there is almost always corresponding wear at the cam lobe. It can't be seen by just looking at the lobes; it takes a degree wheel and a dial indicator to measure the wear.
Jerry