OEM solid roller cams in the BLOCK are not that common. OEM hydraulic rollers are much more common, reduced friction being the primary goal. Horse power being secondary for the most part. Pretty much the same reason most OEM cam have always been hydraulic, easy to use, bullet proof, no fuss no muss.
Most all the OEM solid roller in the block cams (not OHC) are pretty mild profiles. Not at all what we would typically see in a Cobra with an after market solid roller setup. Which would tend to be more of a "race" profile than a "street" profile.
A lot of advancements have been made with solid rollers, getting them to "live" on the street, #1 being a LESS aggressive profile! If you want a BIG solid roller, even with the BEST of todays technology, it's still going to be risky business when it comes to long life on the street.
Never the less, the demise of the flat tappet cam is coming, just like the dinosaurs. The future is in roller's, the cost is already starting to come down relative to flat tappets. Flat tappets will start to cost MORE than rollers in the future and be less available.
Yeah, well, they'll have to pry my flat tappet from my cold dead fingers then...
