I had a trick flow stage 1 in my last car with a Vortech S-trim. Worked great with no idle problems. Had a JMS chip in it. Current car with turbo is idling at about 900 with a trick flow stage 2 cam. How about you idle air control? Is it stuck or dirty? Also, just for grins, you might check your firing order to make sure yo didn't accidentally cross some wires. Plus there are two firing orders on 302's depending on which engine you have. Another possibility is a crack in the distributor cap or internal arcing check it out and look for little burnt trails.