Ran flat tappet in my RB 498 in the Mirada. Only two sets of valve springs ever and the car was still running 9.90's a couple weeks before I sold it. Same Ultradyne cam for 15+ years. New owner had been running 10.2-.3 at a couple different tracks at higher altitudes. 20-50 off the shelf racing oil for years, and then Shell Rotella since 08. I'm sure rollers have there place, but I sure see alot of people running them in dedicated race cars that didn't come close to the number I was running with my junk.

On the flip side we went roller with our W5 small block. After 50 passes we had to disassemble due to water seepage issues and found the bodies on at least 6 of the Comp Cam roller lifter bodies cracked. That was quite a bit of $$$ flushed... Ordered some new lifter from IMM and they lasted 150 passes until the engine expired....and of course hurt a cam lobe so you have to question the integrity of the lifters....so in 200 passes we have one set of junk roller lifters, and one set I probably would question on "re-using". We're in the planning stages for another 9 sec small block, and we'll most likely go with another set of "new" lifters..... but we're stupid like that