NO....well let me explain....NO aftermarket part will void your warrantee....UNLESS the aftermarket part that YOU installed fails and causes some damage, then the damage it causes will most likely NOT be warranteed....like say the cone filter falls apart and its sucked into your engine.....the dealer does not have to warrantee your engine repair.....but let say you put on the intake and you have you muffler fall off....the two are totally unrelated...and the dealer will replace your muffler under warrantee.
you dont think a drop in will make a sound difference will you... i have never had one... i always bought full intakes or turbos for cars... never just a drop in