It depends on what type of setup your looking to purchase, Most aftermarket ewg setups vent atmospheric, I have mine vented this way cause it sounds pretty mean and yields more h.p. from what they say. but you can also have it rerouted back into the d.p. for a more stealthy application. I haven't found a kit yet that they sell like this alone, But i think the Perrin Gt35r turbo kit offers this setup.