flutter issue
 

I have a 92 dodge I recently installed a p pump engine out of a medium duty truck 190 HP pump I rebuilt the engine and injection pump boring the block 20 over and installed a 10 over head gasket it has 140 HP injectors timing set at 18 degrees 4k govoner springs along with 022 delivery valves also 60 pound valve springs in the head problem is the truck has a sort of chugging loping sound at idle and all through the power band I rechecked valve lash and it still does this I also broke loose all the injectors and the all changed the sound of the engine could this be the Injectors I was told 18 degrees timing was not to far advanced with the mods I have

Anyone ?