The pump is stock as far as governor settings. Boost fuel was turned up via rotating the pin, and turning the spring tension down. This I believe started out as more of a noise. sort of a fump fump fump, and intermittent at that. Then it became an intermittent misfire. Injectors are re-built Bosch, though I did buy an extra and I mistakenly chased the misfire by substitution for a while. I don't have a compression gauge adapter at this time. Boost was set to go as high as 20 psi but I rarely pushed it more than 15 psi. My self imposed EGT limit is 1200 degrees, but on a long climb it has gon higher. There is no steel insert above the top ring. As the ring itself wore the end gap became larger, and burned the cavity in the picture.Dennis