I just had a Holley 650 w/electric choke installed with a K&N open air filter with the high flow top. The engine is surging when at a stop while in drive. Accelerating isn't a problem, it responds fine, when I put it into park, it's fine also.Does any one have any ideas as to what could be causing the surge. The timing was adjusted and the carb was also, at a performance shop, but they couldn't get rid of the surge.They set the timing at 12 degrees advanced, with an explaination that I really didn't grasp. Something about when driving it would be around 45 instead of 50
Any insight would be greatly appreciated.