no its not overboared as they are 80mm standard.. my old s2 was bored to 81mm and ran really well at 160bhp but as for 2bar that is rather high.. mine was running at 12psi.. so if you are wanting to run high boost and want it to be religable and safer is with a zvh convesion.. also if you do stick with the cvh you will need excesive mods to the engine.. i.e.FORGED low comp pistons.. lightend and balaced flywheel and crank reground, you will probly need some fuel mods, chipped, aftermarket cam and pully, hybrid turbo.. BIG intercooler to keep the acts the right level. stage 2 head, this may give you around 200bhp at about 14 psi.. as for not doing anything to the engine and try running 2bar within no time it will go BANG!!!