I blocked the hose leading to EGR valve, and also the EGR valve pipe which the hose attaches to. This didn't really help, the car still keeps shooting out the EGR solenoid valve hose and makes hissing sounds. It might've added few more bhp though, not sure. I think I'll have to remove the 1 last cell from catalysator just in case as clogged cat & exhaust gas back pressure caused this last time. But I'm also fairly sure there is still a vacuum leak somewhere as car will make slight hissing sounds when accelerating.

Whats the best and safest way to find vacuum leaks, spray water into the vacuum hoses?