i bought a 96 civic hx that came with a obd1 sohc vtec ZC. dont know much about the engine, except that is much like the D16Z6.
i have an intake, headers, and exhaust. but the car still runs pretty slow.

i dont know how many miles the engine has, but it feels like a lot, is there any way i can tell how many miles it has?

i did the tranny oil change, and the engine oil change( i used a gunk engine cleaner but after the oil change the oil was still dirty, should i use the gunk cleaner again?)

also once i get to about 5,500 rpm, the car doesnt seem to go anywhere, anybody know why?

i have a 93 civic with a d16z6 with 220,000miles, and it runs so much better.
is there anything else i can do to make the ZC run better?

 

Are there any check engine lights?

Is your car going into VTEC? Just because your engine is equipped with VTEC, doesn't mean it is initializing normally.

I/H/E won't do very much for you, so don't expect a huge jump in power. On a single cam Honda engine, I wouldn't expect anything more than +5hp at any given point on your power curve.

 

check engine lights goes on sometimes when im driving.
i dont think its running vtec
a lot of white smoke come out of the exhaust
car is running without the cat.

 

Run a compression test and post your results. That white smoke makes me think your head gasket is messed up, but its too early to assume that, at this point.

 

Is the smoke constant or only at high rpm's?

 

only when accelerating pretty much, i dont think it is the head gasket