I have a 496 Big Block with a 1050 Pro-Systems Dominator on top, Holley fuel regulator pushing 7 PSI, with two -6AN lines running from that to the carburetor, with no return line. The car will start up fine, and will idle after a minute or so of pumping the throttle to warm it up. Idles at about 900-1000 RPM, but will go up to 2000 RPM for a couple seconds and then come back down. It does it about every 15 seconds or so. It surges less and less the warmer it gets and hardly surges while driving. This is just mainly at idle. Now I've heard from other people that have had this problem that it may be starved for fuel and I should run bigger lines, the only thing is is it smells just a tad bit rich. Could be because I'm starting it in my garage with only the garage door as ventilation, but 'I'm not sure how to get it to stop surging. What do you guys think? Also, I haven't found any place that could be leaking. Replaced intake gaskets and they're sealed very well, and checked carb gasket and that seems fine.

 

If the engine is running OK at road speed, I would doubt very much that it is starving for fuel when idling. Most likely the idle mixture, idle speed, and idle spark timing needs adjusting. Also check choke operation, if the carb is equipped with a choke.