do a good decarbonization, both using MCCC and letting it soak overnite and then suck some windshield washer fluid thru a vacuum hose slowly and carefully with some rpms on. Suck in about a liter or maybe more.

With lots of carbon on your pistons or head parts, fuel will soak into it and then evaporate out and be unburned. Quite common, not just for DSM's either but any car with miles on it and/or had sat for a while(JDM engine)

Also double check your cam timing. Simple check on that is to pull the upper cover and then put the car in 2nd gear, ebrake off, and roll the car till the "T" mark on the lower timing cover is aligned with the notch on the crank pulley. When this lines up, check for alignment on the cams. If even one cam is out one tooth, its 12 degrees.