A couple weeks ago I had some sewing machine ticking from my valve train. I run Holley Aluminum heads, crane cam rockers, and hyd lifters. So I went through and retorqued everything to spec. Perrred like a kitten and ran better too. Then I smoked the clutch, been sitting for a couple weeks so today I started it up, pretty loud tick. Let it sit for 5-10 min to see if it would go away...stayed. Could the hydraulic lifters be the cause? I pulled the intake and valve covers back of to inspect and there is no broken parts or bent rods. Oil pressure shows good and it has plenty of oil.