i got a single OHCam vetec in my 93 civic.. shit used to kick hard when i can remember jump on vtec at 5.5 redlined at 8.5

Over a couple of years it started to get weak.. leak oil and burn oil.. but it still has some kick to it.. but not as much... make sure your full of oil.. cuz the vtec won't work if ur low on oil.. at least not with mine less compression i guess.. but give it an oil change and then try it out again