aFe Twisted Steel Headers SS-409 11-14 Ford F-150 V8 5.0L *Race Only*Add more power to you 2011 2014 F150 ? Coyote? with V8 5. 0L engine by installing our new ? Race Only? Twisted Steel? headers. These headers feature a 1 5 8? mandrel bent tuned length primary tubes that will out flow the stock cast manifolds by 46%. These headers are built using 409 stainless and thick 3 8 flanges for a leak free seal. We designed the headers to incorporate a merge collector (header collector). A merge collector combines high flow and