Ok guys, I need some help. Pulling my hair out. I pulled the engine and did rings and bearings and changed the heads and camshaft. I went with trick flow 190 11Rs and a Anderson B31 camshaft. Here is the issue I'm having. I started the car and it fired right off. Idled very good and sounded awesome. I went to set the base timing and shot it with the light and it was 35 initial. I unplugged the IAC to adjust the idle as I adjusted the timing to set it at 14 initial. As I retarded the timing and increased the idle the idle became labored and started to run poorly backfiring through the exhaust. The exhaust temps started to raise rapidly. I shut off the engine. Returned the timing to where I had it initially and started the car back up. It fired right up and cleared up as I lowered the idle screw. I adjusted the TPS and set it at .98v. Did I retard the cam inadvertently when I put it together? Any thoughts or suggestions would be appreciated?