Cam failure has been hotly discussed in a few threads here on CC, it is STILL a burning issue.
The Hot Rod article above (thanks SCOBRAC) is perhaps the best I've read to date on the subject. And I read a LOT about it because I'm running a flat tappet. Hot Rod suggests, among other things, using an engine break in additive ALL the time, even after break in. THAT was a question that has never been answered before here on CC.
Removal of the INNER valve springs is critical for proper cam break in. Run the engine at 2000 rpm or better and vary the rpm for 20 to 30 minutes minimum. Actually after runng my engine for 20-30 minutes during break in I LEFT OUT the inner springs for a couple of hundred miles and kept the rpm low during that time to allow MAXIMUM break in of the lifters\lobes. Probably NOT required as I understand if you didn't 'get it right' during the first 30 minutes, you ARE going to loose the cam shortly there after no matter what you do.
The reason Hydraulic roller cams are now becoming so popular is simple: With the additional
oil pressure\feed to the hydraulic lifter the lifter ROLLER bearings get oiled up real good. With a traditional solid roller lifter does NOT get pressure feed
oil and the lifter ROLLER bearings WILL fail due to
oil starvation when used on the street. Solid rollers are for a RACE motor application where rpms are HIGH and there is sufficient SPLASH to oil the rollers. Lower rpm street use will kill a solid roller within a few thousand miles (mine went 8K before it failed). There ARE new solid roller lifters now available that address this problem, but not all blocks can use them and they are expensive. Thus, roller hydraluics are more popular. Me? Screw hydraulic lifters, real men run solids (flat tappet for me baby)!
