Been out of town and haven't been able to try new fuel mods. To bring you guys up to speed. I installed a return line to my fuel tank right at the fuel manifold at carb with the exact same problem. I plumbed a steel braided line into the cockpit and installed a fuel pres. guage so I can watch the fuel pressure. I can watch the fuel pressure start to go down as I drive. When I start out it is at 6.5 psi. The pressure rolls back as things warm up. There are no spikes in pressure under different loads or rpm increases. I need to talk to the tank manufacture and see if there is a different design of pickup tube that may help this. I am at a total loss on ideas. Any other suggestions would be appreciated. Again this happens with a full tank half tank or close to empty. Thanks. Bermblaster