I'd go hydraulic roller and never look back. It's more torque and more reliable than a flat lifter cam.
Blair, your hatred for flat tappet cams is well known. I know there are occasional lobe failures on flat tappet cams, but I've never had one. I've got solids that have been running for over 25 years that require no lash adjustments. I know of plenty of others that have been used for well over 35 years, in multiple engines. So when people can show me rollers that have gone over 100k miles and last 25+ years of daily use IN AN FE (not in a new engine), then I'll believe that rollers COULD be as reliable as a solid flat tappet.
Not sure I'd call it a hatred for flat tappets. I actually like solid flat tappets. We get them well into the 9's with .500 lift in racing apps, BUT the problem for me comes when I build an engine for a customer, and neither the customer or myself does anything "wrong". No wrong spring pressures, no wrong parts, no wrong break-in, and no wrong treatment after the customers gets it...................and then.................for no reason..........it wears a lobe off after a short time period. Now, if I send that engine to, let's say, California, from Tennessee..... if that customer wants me to fix it, think of the cost to me. I would have to have two more successful builds to recover from the loss on that one. I don't like to build street/strippers for customers with flat lifters because of the potential for it to cost me an arm and a leg "if" it happens to kill a lobe............which is possible. I admit, I have never had that happen, but I know the cost if it did. I have just made a decision to not build aggressive flat tappets for street use. A low rpm, 100 seat, 280 open, 5000 rpm truck engine............fairly safe, and I will do that, but a 160/400 sprung, 7500 rpm flat lifter that sits in a garage for three months at a time.......not me. In that case, it is a cocked gun, just waiting to fail. I would rather do a solid roller and tell a guy he has 10,000 safe miles before a lifter change. Just a business decision more than a "hatred". The oils we use do not have the same "guts" that oils used to have. There is a reason the OEMs went away from flat lifters, and I have grown to prefer the hydraulic rollers on the street. They have been cycle tested at 400 open pressure, and proven reliable, and I am on that program.
