Ok, I have avoided getting into this conversation in the past, but I might as well go ahead. Here goes:
Yes, you are correct, my header will/does make more power than any other headers currently manufactured for the Duratec. It is not because my tubes are longer, it is because my tubes are the "proper length" to create active exhaust scavenging which makes power. The current headers for the Duratec are not even close to the proper length to create exhaust scavenging. They may allow exhaust to flow better than the stock manifold, but not like a properly tuned header.
So why don't the manufacturers make properly tuned headers? Believe it or not, this is a problem for most of the automotive industry, not just the Duratec. I believe there are very few manufacturers that actually understand header tuning. Even if they do, there are other factors to consider.
DONT BLAME THE MANUFACTURERS!
Let me give you 2 scenarios to help illustrate what I am talking about
Scenario #1 THIS DOES NOT HAPPEN
Consumer says to Manufacturer
-Please build me a header that is tuned for maximum power with no compromises
-I don't care if I have to remove the engine to install it
-I don't care if I have to modify some things to install it
-I don't care if it requires special tuning for the O2 sensor to operate correctly so far downstream
-I don't care if the header costs $1,000
Scenario #2 THIS IS EXACTLY WHAT DOES HAPPEN
Consumer says to manufacturer
-Please build me a header that is shiny
-Please build me a header that is cheap
-Please build me a header that is easy to install
-Please build me a header with a cool name
-I refuse to pay more than $400
BOTTOM LINE...the manufacturers are building the headers that consumers are asking for. You cannot run a business otherwise. The reason why I dont go into the header business myself is because of the above reasons. No one is going to pay $1,000 for a header that requires modifications and takes an entire day to install and will require special tuning. They are going to take that $1,000 and put it toward a turbo kit.
Thus endeth my rant.
If someone thinks they can manufacture this header and overcome the above obstacles, please PM me, I will be very interested.