hi, I have an 83 firebird thats been running like crap the last couple months. the water pump went out and it overheated, now Ive replaced the water pump but it still runs like ***. Its only running on 7 cylenders, due to spark, and Ive replecesd the plugs and wires but am still having no luck. I recently found a deal on a mallory distributor/coil set, which I hope (knock on wood) will fix the problem. however, I was just wondering, when I go to install the new unit, how do I get it to line up?

 

If you've replaced all your ignition stuff and you're running on 7- look elsewhere. I have found SO SO many times a massive vacuum leak causing a bad idle miss on these old carbureted cars. They have MILES of vacuum lines. My latest was an 85 that had a cracked vacuum reservoir for the HVAC vent system.

Typically, this will cause not only an idle miss, but also an elevated idle speed, even with the idle speed screw backed all the way out.