|Originally posted by SLOWnSTEADY:|
Motor is the 4.6L from a 1999 Eldorado Touring Coupe (the 325hp version)
You mean 300hp.
The northstar's "easy performance tree" has been picked clean. If you want more power, you have to be willing to work for it. Cams, custom intake, custom headers, custom nitrous install... you get the custom picture.
If you've got the money and the time, build your own intake (manifold). There wouldn't be any down time on your car until you swapped it on.
Headers would be tough to do in car, and you'd have the problem of the exhaust crossover to deal with.
Nitrous is the cheapest and easiest.