The mufflers are not OEM, but rather high-flow performance mufflers. I asked Ford Racing that question before I bought mine (of course, it took forever to get through to them and actually talk to someone). Tubing is also 1/4" bigger than stock.
That's the same answer I got from Arvin Industries (they make them for Ford).
I paired mine up with an MRT catted H-pipe, and it is a real nice set-up.
They were an upgrade for me in terms of size, but I believe the 99+ tips are 3.0" stock already, if so they would look the same for you. They are slash cut. These are them just after I put them on while I was still adjusting the tips, but you should get the idea.
anyone know what kinda mufflers these things are? like chambered, straight through? anybody know what kinda hp if any they make, ive been thinking about these because they gotta have great fit and quality and its a pretty good price too
I'd suspect the mufflers are chambered, though it's hard to know, as the system is pretty rare, so there aren't a lot of discarded ones that can be cut open to confirm...
Ford Racing claims that the catback provides increased flow of 7 - 10%. I don't know what sort of hp that translates to, maybe 1-3?
The tips are the same as the stock ones (99+), the fitment is perfect and it's stainless steel, which is nice. Overall, it's OEM quality. Judge for yourself what that means...