I'm thinking about switching to a solid roller from a HR in one of my BB motors.

I have a like new (maybe 10 passes) of the Morel Small block solid lifters I ran approx 7200RPM in my 414 and I think other than the small blocks having a V notch in the link bar they are the same lifter. I test fitted a couple pairs in an old 440 I have and they seem to clear fine even at the extreme of the link bar travel. I know you can't put the straight link bar BB style in a small block (since the valley has little nubs sticking up) but it seems there would be no problem at all going the other way from SB to BB. And AMC's I believe are the same as BB (straight link) as well except AMC's pressure feed the rockers through the pushrods and have a bleed hole in the lifter cup for that purpose.

The Morels have a long (HR style) body so when I ran it on the smallblock I had to use a much shorter pushrod, But on an RB the longer body might actually be an advantage.

Am I off base? I's there another difference I am not aware of?

You have to ask yourself if the SB ones will work in the BB as well why do they make a separate BB style?

Maybe only because the BB won't work in a SB (Sb have a V notch in the link bar for valley clearance).

Allow me to reword it, If the SB ones will work in a BB why do they make a BB version?

Because if you order for a big block you are going to likely use it in a big block. If you know the small block works in either then you could order and use it in either.

Okay....But why not make a universal fit setup? The non roller tappets are the same for most LA and B/RB blocks, right?

Yeah thats what I'm asking, is there something else that I'm overlooking?

On the surface the SB look like they (at least the morel design) will work in a BB.

Call Brian at IMM Tel.760-347-5493. I believe he was involved in the R&D of the small block Comp Cams roller lifters. I believe there is an oiling advantage to them at idle?

That makes no sense at all.

Point I am making is that there is likely an important difference or they would not make a BB version in addition to the SB one if the SB one would work in either.

Though I suppose it's possible one was designed first then much later the other was designed as well and not being Mopar savvy they didn't realize they didn't need both. See that often.

Been a while since I messed with small block rollers but I thought back then the guide bar design was unique between BB and SB. You could use the SB in a BB but not the other way around. The lifter angle is much different on then SB and the lifter is aimed at the water jacket wall where the BB runs more parallel to the wall.