My stang has a rebuilt engine with the mods in the sig... everything else is stock, including the original E7 heads. WHen I first got the car the engine made a ticking sound and it is constant through all rpms. I changed the oil and the noise is still there, it may be my imagination but it has gotten louder.... it sounds like a train almost. THe ticking sound is louder than my exhaust at idle!! It sounds like its a valve train problem opossed from a exhuast leak. How can I tell from the 2? I dont feel any air leaking from the heads/headers.