78 cutlass supreme

I have a 1978 Cutlass Supreme, with a 260 v8 in it. When I bought the car, it had been sitting for 10 years, and I couldn't keep it running, except by dumping a little gas down the carb. I put a new carb on it it ran great even on the old plugs that where in it. Changed the plugs, wires, cap, rotor, and fuel pump also. My buddy came over and adjusted the carb on it, and it ran ok. After that it started fowling out plugs, and smoking a white blueish smoke. It also has oil coming out of the exhaust. I'm thinking blow by, maybe valve stem seals, since has been sitting so long. But I had another guy tell me maybe the carb wasn't adjusted right and that would cause all the same problems. ?????

white smoke usually coolent,blue =oil , blk = to much fuel. blow by you would see extra air being forced out of valve cover with cap off and running some is normal. valve seals go on gm's but can work in if you run veh awhile can also try additive in oil. A compression test would confirm or rule out blow by though.Carb can't throw oil into cyl's