I have a newly rebuilt engine on my 1965 Austin Healey 3000. When the engine is cold it makes a popping/backfire noise. After the engine has warmed up for 10-15 minutes, it doesn’t make the noise anymore. See this video at 0:19-0:20 http://www.youtube.com/watch?v=7RBCqWILnRU&feature=plcp
Thanks in advance.