i hear everyone talking about a "sewing machine" sound when running an aftermarket cam. well i hear something coming from my car but cant distniguish exactly what it is. it is like a soft tapping noise that can only be heard from the interior of the car, is this the "sewing machine noise"???
i just installed my cam, and im afraid of punching the gas because this noise is making me think its a lifter knocking, eventhough i cant hear anything when i open my hood.

 

yeah, probably if you did not hear the same noise before the cam swap...

how big is your cam? Did you also swap springs, pushrods, lifters, rockers or anything else in the valve train?