The only problems with KBs I'd had were the very first set, I failed to read the ring gapping literature. So I had to pull it apart and replace the rings for free. No damage, just I got nervous because I knew it was wrong. I've seen teh tops pull off them, that's because someone wasnt as nervous as me, and let the gaps stay too small. The ring butts, and then siezes, and the top gets pulled off the piston, or ting lands break. That's not the design or material's fault. I dont blame parts when I screw up...lol.. I have 5 engines with them right now, one uses a 125hp NOS shot. It has over 500 passes, the last 150 or so on the bottle (against his builder's advice
). Others have over 30K miles in various vehicles. 3 street/strip cars, and a truck. No failures, no noise, no problems.
Same deal with the cams. If you build enough engines now a days, you will not lose a cam. I can wipe a lobe off anybody's by ignoring certain things that in the past you could ignore. There were few "MUST DOs" when I started doing this stuff. Good geometry, the right lube, getting it to fire right away and geting the rpms up. Now, it's measure the lifter crown (if you can) and lifter bores, check for lifter rotation in the block, remove the inner spring(if equipped), make sure the geometry is on from the offshore $100 roller rockers, measure preload for the right pushrods, use the right lube on the cam lobes and only lifter bases (not the sides of the lifter...), use the right oil (not the "emissions" std motor oil stuff) and supplement if needed, preoil and make sure it fires on the first turn and the speed is high enough. If all that's right, the cam will not wipe a lobe. Whether MP, Comp, Engle, Crower, or Edelbrock grinds the lobes.
From what I understand, there are only 2 cam blank manufacturers for every cam grinder in the US. "Soft cams" are a figment of ones imagination fueled by guys "passing the buck" because they missed something. Bad lifter crowns are a reality...not bad cams. Cam lobes are not ground "for a manufacturer" ala GM, Dodge, Studebaker. They are ground for lifter diameter now. I've seen .904 lifter Chevy and Ford cams. Ramp speeds cam be faster for the same "size" lobe with the bigger diameter, so the others put in the larger size. Every lobe has a rate of lift determined by the lifter diameter and type, a "bump" to take slack form the valve train before the real lift begins, a max lift, and a few degrees on the closing side of the lobe to ease the valve onto the seat. Make doesnt matter. For my cam choices, I want accuracy. MP cams stick now. try degreeing more than a couple. The worst was so far off in manufacture, I had to use an offset key in the crank plus a bushing to get the thing to the recommended installed centerline. It was ground 9° retarded. I havent used an MP cam since. Not because the grinds are bad, because the low bidder approach isnt getting the accuracy I want. A Comp, I may have to move a max of 2°. Most I never have to move at all. Same with Crane. I'll use and Engle at some point..I just havent yet. If they degree good, I consider them a "good cam". The lobes I spec by choice, the manufacturer has to put them in the right spots.
On a side note..I keep wanting to think I'm dong this...
Sorry about that
