They are extremely small. Ford needs to pull their collective heads out of their collective asses and put some more cubes into the car, which I think they will do shortly (5.0 is the rumor). The '03 Cobra is no slouch, though even with a tiny 4.6. The 4V heads LOVE the boost, and with just a headers--back exhaust, pulley change, and couple other bolt-ons they'll lay down mid-upper 400s (rwhp) on the dyno. Stock is about 350-370rwhp (SAE).