J.D.: I had a similar problem on my 261, and obviously from the good feedback it could be a lot of things that cause that problem. For your information, in my case, I installed new points and set them as per spec. It ran fine at idle but would hardly run beyond that. I found that the points were not opening & closing properly at speed because the mechanism that was supposed open & close them was not aligned properly. Even after buying another new set it don't work. It seemed like they weren't the correct points. I tried the original points & it worked fine. I eventually went to a HEI from Langdon & it works great. Just another thing to check. I find that when something unexpectedly doesn't work, in my case it is the last mechanical adjust/alignment oriented thing I did that is the most likely cause.
