Ticking down below

The car started making a ticking/chattering noise and it sounds like it is coming from under the engine somewhere, mostly when I take off while rolling out of second gear. The car doesn't lose power at all. It won't tick in neutral or park. Only when it's under load and the more I accelerate the faster it ticks. Also it is not a steady chatter. It almost sounds like 2 steel transmission lines hitting each other. I jacked up the car and made sure the lines are all secure.
Would a leaky header sound like that? I was thinking maybe where the exhaust hooks up to the headers, but it only ticks under load. Also I thought of the roller rockers. What do you guys think it may be?
thanks

Sorry, I wasn't getting much of a response in tech so I posted it in talk. Anyways, would an exhaust leak only make noise under load?