I can make mine pop stupid loud by turning the turbo timer off turning the key on and off at about 4k revs haven't done it in ages though as it's not good for it lol
I agree with the above with the rings issue no one is going to want to go near it. I think this one is going to the scrap yard in the sky after all good bits removed and sold
Check the thermo isn't stuck shut if it's not I'm sorry to say your head gasket has gone pressurising your coolant system with co2 get it sniff tested at a garage for 100% if it's gone.
So bodged the skirt today starting to hate them don't fit for shit and it's winding me up going to have to get a body shop to repair and make them fit for me