I'm pretty sure the SBF exhaust manifold pattern is entirely different than a Vulcans. Also, the headers you buy still have to fit in the engine bay, just because they bolt up doesn't mean it'll work.
edit: I guess didn't read the engine type, but the 3.8 is different too, afaik.
With headers you're paying your money to extract the exhaust in the quickest, smoothest way possible. In a race car there may not be body restrictions, in a street car there is so if you do want headers buy something that fits.
By the way I think headers are the best bolt on performance inprovement out there. Powder coating them also is money well spent.
A forum community dedicated to the Ford Taurus and SHO models, Mercury Sable and Lincoln MKS. Join the discussions on EcoBoost, aftermarket performance, and more!