hmm! 1 Bar=14.57 psi
for a 5-9 psi intercooler is not necessary.
BOV is not required with the stock electrically controlled clutch.
EGT does not increase due to high presure.If done properly there would hardly be 6psi increase in the max compression prior to combustion.
a 6psi increase in compression should result in around 40% gain in torque.
U should be worried about not to break the ring skirts(failure of compression strock) rather then melting ur pistons. the skirts crack alot earlier then the melting point.
Supercharging with CNG with a Conventional type of venturi means u r looking for problems. The reason is that a venturi n these kits can not control the vast variation in the amount of fuel required during different driving situations,i.e, going in low RPMS with no boost n vice versa.