^^^ they dont have to change the cams on a forged engine, it usually comes as an extra, To reach 250bhp with a td-12 you will need forged intrernals and more than likely cams with head work. They turbos are warrantied up to 1.3 bar so thats really the max, So far its a good turbo but with not many results, Also you are aware its a externally gated turbo, so a manifold to suit is required along with extarnel waste gate, uprated bov, relocated filter and uprated rocker cover breather. Gary