71 Duster 360 turbo build

Oregon camshaft did not have a valve spring recommendation for me. He just said he wouldn’t run more than I already have. Another shop I spoke with stated they typically run 170-420 with magnum lifters. I’m running Elgin HL-2269s lifters where are supposed to be a slow leak down type. I have 2.5 turns of preload on them which I’ve seen recommended for factory lifters. It was suggested that I try 1/4 turn preload since they’re slow leak down. Maybe I’m experience pump up?