I think there's a gain to it. It'll help circulate air better while driving. If you're just parked and the dyno then I see no gain.

 

cooler air

 

Cold air gets under the hood through the grill opening when driving. You don't need the duct for that.

That duct routes some of that outside air blowing past the top of the cone filter towards the fender and fusebox maybe. I don't see how that can be helpful to anything.

 

If you have an open filter and are making let than 400whp then theres no reason to not use the stock box with drop in. Sucking in hot engine bay temps is retarded. The stock snorkle forces cool high pressure air from the nose of the car right down the filters throat. Hard to beat that unless you have a very big turbo.

 

Cone filter will hold more boost up top, whether you make 400whp or less. So it is beneficial to most people.

 

No, get ridof it, its benefit is less that taking out the rubber piece that seal off the top of the headlight to the underside of the hood. I have 30+ datalogs to show the snorkel does less than removing the rubber piece. On my specific car, I see AIT's only 7* above ambient in a steady state cruise.

Remove it along with the rubber piece, and you are good to go..

 

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