[Formulajones]

Originally Posted by dataway

I wonder how many HFT failures were using stock grind cams, or modern replicas of stock grind cams, as opposed to modern profile cams.

If you filter out high performance cams and high spring pressures I wonder what the failure rate would be.

I'm curious .... did high performance cams of 40 years ago use similar profiles to modern HFT cams, or are modern cams more abusive to the valve train?

Hard to say if one is more prone than the other, I just haven't seen the failures with flat tappets. I run as much as 130 lbs. seat pressure on some flat tappets without issue, using modern grinds from Comp, while other cars here have stock camshafts or even 50 year old grinds from Isky that still work fine. There are some benefits however to the more modern lobes. But like I said, I go through extra lengths on mine with nitriding and pressure lube lifters etc... so a typical flat tappet for me runs about $1000. A hydraulic roller for me runs about $2000, sometimes more by the time I get the $1100+ lifters, etc... So the price difference is about double. Not horrible but not in the budget for many.

Like Mgarblik said, I really think these failures are just bad luck with a few other reasons mixed in, many of which aren't the cams fault.