Bit more specific info needed. Most, but by no means all, conventional airliners have under-wing engines in pods i.e. the thrust line is below the CG. This results in a pitch up moment on thrust application (delayed as the engines take some seconds to spool up). If you have a thrust line above the CG (like in many bizjet designs) I imagine you'd have the opposite effect i.e. a pitch down, all else being equal.
If you're talking about piston-engined aircraft this, I suppose, could be complicated slightly by propwash over the wing/tail giving slightly unexpected (at first glance) pitch characteristics.
Do you have a specific example? Hope the above isn't too simplistic - not sure of your experience...?
B&S