What routine/routines, rep range and amount of sets per bodypart are you using, mate?
Just reread your post.
You could try cutting back on your all out effort on your other bodyparts, just maintain things as they are for those, so you can put a bit more effort into your arm and chest exercises.
Mind, saying that, what the f**k do I know, can't even communicate what I'm trying to say on the big cat thread, without people thinking I'm a snidey, provoking c**t?!! .
Good luck with it, mate.
A lot of trial and error involved with the old weights game.