Been running 19psi all this week through my cossie managed series 2 but today when I've nailed it I noticed it was popping and banging really bad once the revs hit about 5k. Checked the boost gauge and its reading 28psi when on full chat.

Checked both amal valve hoses and turbo hoses and cant see any rips or leaks etc, not running a bleed valve wither.

Any other reasons why this has now started to occur? faulty amal valve?