355 Small Block

[big dwag]

Heres the problem that i'm having with my 75 nova, It has a 355 motor,with a new 306 cam .555/.555 lift. with new lifters (hyd) and matching push rods & valve springs, & rockerarms (1.6). everything that the cam specs called for. I adjusted the rockerarms while the motor was running, after all rockerarms were adjusted it still makes a chattering noise, while driving it if i try to take off fast then it feels like its not getting good fire or the valves are not closing all of the way. I have when back and adjusted the valves again. i tryed to leave them a little loose so a wouldn't overtighten them. still the same thing chattering and when i turn off the motor then the rockerarms are to loose. Is this normal for this kind of cam lift? I haven't givin up yet i know what this motor can do, Just have to get all of the bugs worked out. Can anyone give me some tips. Thanks.

[1slick1]

its hard to explain but here goes.....with the engine running adjust the rockers back until they chatter then adjust them back until they stop then turn the nut 1/4 of a turn. this is how i do it you be your own judge. the rockers getting loose is another thing, you need poly lock nuts, not aircraft nuts which have plastic crap in them, poly locks have an allen head screw that screws down in the top of them to lock them in place. you need to lock each nut in place as you adjust that valve. this is the only knowledge that I can give you but dont give up. Fine tuning is an art. Good luck!

[Thunderbolt]

Did you have any machine work done on the heads for the valve springs ?? If I am not mistaken once you reach .500" lift on a small block chevy the heads need to be fly cut so that the valve springs don't bottom out. Your problem is compounded when using 1.6 to 1 rockers instead of 1.5 to 1. This may be your problem with how it is running, But I am not sure on the noise. I am only guessing , But it may be worth checking into.