I received my Plunger and spring from Vintage Power Wagons today. As you can see in the picture the new(used) plunger is in much better shape than my original one. The spring they sent me was too short so I ended up using my original spring. Once installed I ran the car and the oil pressure went up to just above 40psi. I let the car warm up and noticed the pressure was slowly going down. I would rev the engine and let up off the gas and the pressure would shoot back up to above 40psi then slowly go down again. I went for a drive and the pressure would drop near 0 then when I would shift gears and let up off the gas the pressure would shoot up to 40psi then slowly go down near zero when I was on the gas. I found it very strange that it would shoot up to 40psi when I let off the gas to shift gears. When I got back home I sat in neutral and reved the engine steady and oil pressure would hold @ 40psi. I decided to change the oil. Went for another ride, same thing happened but when the pressure would drop it was not as near zero as it was.I think my spring might be weak? The spring that Joe sent me should be arriving any day, I am curious to see if his spring (green spring) is going to make a difference. What are your thoughts?