Originally Posted by Muffnbluff
D'oh, I missed it!
That's awesome you get to work with stuff like that. So are the headers really as good as Ford claims when they say people won't even need to look to the aftermarket because the stock ones are so good?
Keep in mind I only saw prototype headers, but they are typically as nice or better than production parts since they are lower volume and not outsourced.
I will say that they aren't as good as the OEM headers on the S85 M5/M6s, and if the S65s are of similar design (haven't seen a set up close, yet) they aren't as good as them either.
The S85 headers are incredible with the cats removed and a properly shaped/sized cone inserted, honestly I think they are the nicest OEMs I've ever seen on a car. V10 M5/M6s with this primary and secondary cat delete with an otherwise stock exhaust regularly walk on (hard) full S.S. exhaust cars with no cats in the Gulf. All else equal, even software (and they even swapped complete exhaust systems on two otherwise identical M5s to compare) same result with both cars. Major props to BMW for that. The 63 manifolds are truely garbage by comparison.
Anyway, yes they can and will be improved on. 70-80% of overall power gained from a LT design vs OEM log (which have come a long way in the last decade even though they aren't pretty) comes from the collector design. Definite improvements to be had in this dept. Also this motor needs 1 3/4" primaries and aftermarket 300cpi high flow cats or off-road mids will always gain vs an OEM 500-600cpi met. cat.