O.k., my stupid 87z is giving me problems. It runs fine and doesnt really have any serious problems, but ever since i rebuilt the top half of the carb, the car has taken on a shakey idle. It'll sit there in whatever gear, and if you pop the hood you can see the motor wobbling around. The motor mounts are good and all seems well, but the miss is evident. Off idle performance has been hurtin too. I cant even spin my tires off the line anymore. Before i rebuilt the top half of the carb it wasn't a thing to roast em. I changed my knock sensor at the same time as the carb rebuild. I have an edelbrock performer manifold, msd coil and 6a ignition, no cat, 80 series flow, open air element with the timing at 0. When i ran more timing (6-8*) it helped my off idle performance, but the shake at idle was worse, and it would occassionally diesel. Becuase of these problems, my car ran that 15.8, i know it can go low 15's but i cant get anything out of the hole anymore. Can a float be to cause? I put a new float in and didnt adjust it. Plus, i can hear this tapping sound that is consistent with engine rpm (sounds like a lifter) and the sound will come and go throught the day. Could a bad lifter cause these problems? I havent gotten any codes, but my alternator is on the way out and the choke light will come on on occasion. Thanks in advance.

 

Check for vacuum leaks.