I have a b16a2 in my 91 integra. I have a pr3 ecu, but I have an Apex'i VAFC to control the vtec. After reading this post I went out and tried vtec at 4400- it dosent bog at all. it dosent pull like it does at 5500 or what ever, but it still pulls. I even tried 4000 and it still dosent bog. Also I have seen MANY different variations of a Mugen program. My friend got a p30 chipped for DOHC vtec, mugen program at Ericks racing for his car(93 civic hb si with jdm itr engine) and the vtec didnt pop till 6500 and the revlimit was at 9800. 4400 sounds like maybe a single cam vtec crossover.
Also get yourself a timing light(nothin fancy, just a plain old timing light.) that would help you when you move the distributer bring the line on the water pump as close to the center line of the 3 lines on the crank pulley.
Correct me if Im wrong, but I think there is a article on VTEC not working, and things it could be.
OBD-0 ECU's throw codes thats why the light on the ecu is there-to check them. Any CEL for any thing in the seventies is a cyclinder misfire. 73 is cyclinder 3 misfire.