The springs are not all that old, I had them put in last summer, that is what is really getting my goat. I swapped out the HLA's hoping that was the problem, but no luck there.

One thing that I was going to try, after we get moved to our new house, is yank the springs off of my other turbo head and try them. When I had my old 'D' port head on there, this 'flutter' did not happen, but when I changed over to my oval port head, the flutter started. I later got tired of chasing this and put the 'D' port back on it. Problem went away. But an arrant bolt took that head out, along with a piston and 3 cracks in the cylinder wall, and I had to go back to the oval port head. And to no surprise, the 'flutter' came back.

Thanks for the advice. I just needed to get an idea as to what ball park I was in and where I needed to go next.

Jim B .