I just picked up a 76 K5 with a built 454 in it this weekend. I didn't buy it from whoever built it so I don't have much info on it. Anyway I was told it wouldn't start so I replaced the cap, wires, plugs and it fired right up. One of the wires was too close to the header and got a little hot and the truck wouldn't start anymore so I bought a new set. Put them on and it fired right up. I drove it home and started it two days in a row first try. On the third day it wouldn't start again. It sounds like it did before I replaced the wires. I can get it started but it won't run without half throttle and smokes quite a bit. It has an MSD ignition and coil (no HEI), could I be burning the cheap plug wires from the inside out? When I was driving it home it was hesitating quite a bit if you stepped on it under load. Is it possible the distributer is one tooth off? Any ideas? Great forum by the way.