What fuel is in and what is it tuned for ? Is the first and easiest thing to check .
How qualified is your mechanis to know what detonation is ?
If you trust his word then yes get it on a dyno $60 for a dyno run is a **** load cheaper than new pistons
Turn the boost down and dont thrash it untill you fix both of these issues .
Tbph this thread reads like a troll of a rfb page on face book .
What is youe motor worth ?2k minimum . Right so dont be dumb, now go and buy a 200 alloy radiator off trade me and get someone whos competent at bleeding the coolong system to help u after u change it
Fixing a radiator with kneedit is fine for paddock cars . And nothing else . Potentially as a get u home from middle of nowhere scenario .