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I converted to a roller in a street car around 1994. The reason was that I wiped out three MP cams during a short period. I have used dozens of different cams since then in different build ups. In my opinion, there isn't an absolute truth here. There really is a reason why the OEM manufacturers use rollers nowadays too, it just makes more power than a similar flat tappet. It also accepts way more aggressive grinds, which requires and can use way stiffer valve springs etc. That of course stresses the other valvetrain components alot more than a flat tappet will ever do. However, a similar flat tappet would kill everything + itself there immediately. In a race car with frequent checking and maintenance, I would say go for it. And with an aggressive race grind. In a streeter, if you pick a "street roller" that doesn't require extreme spring pressures etc., I would say that the relaibility is at least as good as with a flat tappet, but the manners and power better. The real question is, that is the advantage for you worth the 1000$ or so you have to spend upgrading?



What I understood for the switch to roller cams by the OE's was that in the mid 70's when Catalytic converters and unleaded gas became the norm in the US, the converters started getting contaminated by the zinc and other oil additives that promoted better wear on bearing surfaces. When they started cutting the zinc in the oils to save the converters the cams and lifters started failing. I remember a rash of bad cam and lifter failures in a lot of 305 Chevy's in the early 80's that may have been partially due to this. So to get around the loss of wear additives, the OEs switched to rollers.