hi freddy,never heard of king pistons but as regards to them holding 1.1 bar of boost which is equivalent to approx 16.17 psi,at that boost level its the air fuel ratio thats important as even the most expensive pistons will melt if thats incorrect
i take it that it has a modified chipped,as i think the standard one has a boost limit of 12 psi after which if exceeded the engine cuts,