Dan,
Yesterday, after two and a half years of torture with my Holley Fuel Injection and two different shops trying to diagnose the problem during that time, we tore it all out and re-installed an Edelbrock carb. I also had trouble for many years with my carburetor, to the point where starting it was such a pain in the rear that I gave up driving my Pantera (especially because my new to me Jag XKR was quicker, easier to drive, and so reliable). When I restored/modified my car starting about 7 years ago, the first thing I wanted done was to change to fuel injection. After that, just turning the key started the car up immediately, and I was excited. But, on the first day of bringing it home from the shop that did the work, I experienced what seemed like vapor lock. Car would begin sputtering, then stall, and it would have to cool off for 20 minutes before it would run again. During the couple of years that I had the system in, if I drove the car on early winter mornings where the temperature was 40-50*F outside, I didn't have too much of an issue, but when the temperature rose, and/or I was in traffic or climbing a hill, it would continue to leave me stranded in some very dangerous situations. My warning about Holley is that they are not answering phones so you can't get any technical help from them right now. About 3 weeks ago I and my mechanic spent over 8 hours on hold trying to get some information from them, and phone was never answered no matter what department extension you tried. Yesterday, we chucked the whole thing. If you want a near new Holley system, and can diagnose the problem, I'll virtually give it away. My car was delivered back to me late last night, so I haven't driven it nor started it yet with the new carb, and I won't be able to for a couple of weeks due to foot surgery, but I'm anxiously awaiting a drive where I'm not scared to death of stalling in a major intersection or a freeway offramp or on the freeway, as that happened everytime the engine temp got to 180*F. I was down at PIM a few weeks ago with a friend getting parts for his Pantera, and I spoke to Jerry there who said he has ripped out many fuel injection systems from Panteras over the years and highly recommends against their installation in the Pantera. I was intent on keeping mine but didn't want to order a new ECU without knowing that was the cause only to have it happen again. If we had been able to speak with Holley tech service at any time, maybe they could have give us some information that would have simplified a solution. Unfortunately, they are completely unresponsive. I cant wait to try her out again soon.