Full fat Stage 3 setup

[Ruan]

I'd say the only things required are decent exhaust, the manifold is a bit shitty and can probably be improved, if you're fitting a decent turbo, you might as well anyway.

Valve springs/lifters or whatever you want to blame as this fabled problem - unless you know the exact reasons for this happening and the exact process involved and you are suffering with the problem and you cannot fix it, why touch them? Currently everything you're reading is speculation and rumour - even I'm speculating, but I've a pretty good idea as to why it happens, but I won't say because otherwise there will be this massive obsession that before you know it, it'll be a requirement of all stage 1 cars to have a modified valvetrain. I've experience of one person who's run into proper valvetrain issues which was solvable by adjusting a few components. Until you know you're hitting the problem, know why you're hitting the problem and can't solve it, leave them - you're likely to open a massive can of worms by playing with the valvetrain and AFAIK nobody has done any thorough testing and it's all massive speculation that it will fix the problem.

A modern, well setup turbo with a good exhaust should mean you never see the problem anyway.