I think the '03 Cobra's factory ratings are very modest. All you modular guys probably know that when you strap a blower on a 4V it makes crazy horsepower. I'll bet money the '03 makes a helluva lot more than 390 at the crank. Because even with stock heads and intake the Cobras can make well over 400 RWHP with modest boost. I think Ford is keeping the factory ratings down to lower the cost to insure a Cobra and to avoid '99 Cobra incident. The hot ticket when it comes to modulars is definitley forced induction, and contrary to popular belief, the modulars are very strong even with the stock shortblock. They are stronger than most of the newer 5.0's ('93-'95 weren't as strong as the older engines). The modular engine family's potential is now starting to be realized and this is only the beginning. You can find every you'll ever need to know about the modular engines here
www.seanhylandmotorsport.com/modsquad.html