Is the CBV blocked off or did you just remove the diaphragm and spring?
An easy way to check for vacuum leaks is to start the car cold and bring it up to a medium idle with a helper. Then get a can of carb cleaner or similar and start spraying around the various connections and hoses. Listen for any change in the sound of the motor. Ive used this method several times to find leaks that arent obvious to the naked eye.
I would also be putting that CBV back in, they dont cost much and you dont gain anything by removing it.
http://www.ebay.com.au/itm/MAMBA-BLOW-OFF-VALVE-BOV-Bypass-K5T09671-Mitsubishi-SAAB-VOLVO-HYUNDAI-TD04-TD05-/182545114845?epid=20003833668&hash=item2a808966dd:g:FpUAAOSwPYZU9UAc