looking for help troubleshooting

ive been having a few problems with my car, ive tried just about every idea ive had, and i cant seem to figure these out. btw i am running a 90 4 door with a b16a block/b17a head

Vtec not opening correctly-it seems like my car is running very slow when vtec should pop. i hear a click and i dont loose power, i just dont think i make as much power as i should. i tested the solenoid and theres no vtec CEL’s. the vtec on my 95 gsr used to hit like 4 times as hard. i tried a friends computer which is chipped, and you hear vtec pop like crazy, but dont feel anything at ALL.

Battery draining-everytime i leave my car for a few hours the battery dies and i have to get it recharged. i cant seem to figure out what it is. the only aftermarket electronics is a cd player and that doesnt seem to be the problem. any other ideas or testing techiniques? i dont want to take the time to go through every wire in the car with a test light if its not neccessary.

Idling problem-My car idles very weird sometimes. it varies from 1k-2k going up and down. if anyone has a vaccum line diagram for a b17a it would be greatly appreciated. other than that i dont know what it is.

Oil light-after about 10 minutes of hard driving and i start to slow down my oil light comes on. the oil seems to be actually a little over full, which i dont understand because i only put in about 4 1/2 quarts which i thought was the right amount.

Vehicle speed sensor-its disconnected and im putting in a new one when i get a chance, just thought it may help to let you know it is disconnected.

also i will be replacing the O2 sensors.

any ideas on what these problems may be? the car is running pretty reliably other than the above, it just seems slow for the setup im running. i bought the car not running, so i dont have any previous experience to base it on besides comparing it to my 95 gsr. (which i think should be at least somewhat comparable)