Another edelbrock carb question!

So I advance my distributor only 2 degrees and the started did the kick back thing so I set it back to 16. Then I set my idle mixture screws to where I get highest vacuum (turns out they were out way to far, about 3 1/2 turns). I drove it around and all felt well then I changed the step up springs to the pinks and it feels great and responsive but before I even messed with it I drive to my buddies house and the idle was jumping around. It would idle real low around 500 then go up to around 800 then back down etc. does that sound like it could be a vacuum leak? And Moper, it's no so much the smell that bothers me but it loading up. Thanks so far for all your guys input! -kory