So I have a 79 brat, just rebuilt the ea71 less then 3k miles ago. I put a delta can in it, new bearings had everything balanced.it has a weber 32/36 and a ea81 electronic dist. Now my issue is that when I drive it on the highway, it likes to die at an idle after I get off the highway. It usually idles between 800 and 1000 rpms and after a good stretch on the highway it gets down to 500 or 400 and will die. Any thoughts?