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hi brother's,

need some advise on a stock evo 3 engine.my bro had just converted his perdana engine to a evo 3 engine.the thing is wat are the parts to be changed or install to get atleast 1.5 bar without effecting the engine with a minimal cost.tis is becoz his mechanic told him that on a stock engine if we set the boost to 1.5 bar is dangerous to the engine.is it true n plzz advise in this matter.your advise is much appreciated.thank u brothers.....