I just got my X 1/9 running after sitting for 8 years. it runs great the only issue is that when it is idling it surges between 1000 and 2000 rpm. this does not happen when it first starts but once it warms up a bit it does it and wont stop. any ideas?

Check your ignition timing, I think you'll find the advance is wondering all over the place and since this is a federal spec engine you have a vacuum feed as well so it is either your vacuum feed or the mechanical advance.