Valve hydraulic lifters... UPDATE... SOMETHING IS WEIRD HERE

[Brass]

Nacho, I admit to not reading this whole thread but for what its worth, I have the same cam you do.  I don't have the part number handy, but I went with the Crower lifters (made in the USA) they recommended.  No problems yet. 

[Nacho-RT74]

well, the main deal is... if 976s ( is a common PN from several manufacturers ) is designed for BB, and on lifter specs doesn't say ANYTHING about some lift or cam discrimination, why didn't work on my engine. They are simply FOR BIG BLOCK IN ALL CATALOGS ( including MP )

then if the MP lifters coming with the MP cam I got initially ( and MP 280/474 cam specs are not so much different than the Crower 282HDP ) are the same geometry than the HLJ 976 lifters, does that it means the MP lifters WITH THE MATCHING CAM I got from MP weren't to work either ?

UNLESS the base circle is diff between the MP 280/474 being smaller and the Crower 282HDP being bigger. But if so another doubt comes into my mind.

If I wasn't got the adjustable valvetrain, how a stock rockers system with original lifter and pushrods specs was to works fine on a smaller base circle piece if with an smaller base circle camshaft the distance gets increased between cam in rest position and rockers ?

AND EVERYTHING OF THIS is just IF the problem with the HLJ lifters I got really was they got unloaded ( making the noise ) because the oil groove was leaving the lifter bores, what Still I dunno if it is that the reason why I got a "machine gun" inside my engine.

Sorry, Dunno if all what I wrotte sounds clear

[b5blue]

   It's clear Nacho. You got what I mean about lift needing to clear the inside diameter of the smallest cam bearing. (Yes that they go trough for install.) Again checking my B/RB book Mopar is clear that "cut to fit" push rods or adjustable rockers or adjustable push rods are the only way to be certain of correct fit. Keep in mind at no time do they say all cams from all manufacturers have same "high point" height from the center of cam, only that lift is a function of ratio from base to top of lobe. (That lobe can only be so high to fit inside bearings.)
  Thinking about geometry of valve train on any engine other than all brand new, pushrod length is critical even with adjustable rockers as adjustment must fall into a specific range.
  I read and reread this section in my book many times and all this had much to do with picking my P4452783 cam (268/284* .450/458 lift.) for my build. I only wanted to deal with known, proven parameters for my build even if I leave some power on the table not in the engine, for reliability and certainty of tuning. Yes my plan did include Crane iron adjustable rockers but I can't buy what they no longer make so it will be adjustable push rods from Smith Bros. now for me. With the issues you have had I'm going to try the adjustable push rods BEFORE adding Johnson lifters!   

[Paul G]

Natcho, are you sure you are getting enough oil to the lifters? Good oil pressure?

[Nacho-RT74]

gauge reading is at the top. With warm engine, is around 3/4... once cranking the engine with valve covers off, got oil everywhere LOL

[71green go]

Nacho........what was your finding here?
Johnson Just sent me B-0976 lifters also...........did you try the 2001's?
Let me know!

[Nacho-RT74]

I tried both, just which suposselly are SB worked... 2011s

but MP BB camshaft kits includes same kind of lifters than 976s

As I stated, maybe the crower camshaft base circle difference with stock and MP shafts, then height at lobe makes the oil groove leave the bore ? really dunno yet

I have to make some revisions on my engine build so mostly sure will dissasembly it again and will take the chance to check that