thanks guys. i´m from sweden and my english is not perfekt. but i have an 66 dart gt with 318 engine. i have restored the engine but 5 lifters have collapsed after breaking in. engine parts is eddy performer, eddy 600, 302 heads ported, original pistins, new rings, new sealed power 340 camshaft, new lifter and pushrods. original rockerarms and new bearings stock exhaust manifolds but homemade dual 2,5 inch exhaust system. cam is in great condition. and i wonder what happened with my lifters.