It made 560hp. And what are you saying here anyhow? That it didnt make 90hp and 100tq more than this 340?
The 418 used the same intake, same size 750 carb, and same size headers as this 340. We left a lot on the table with the 418, but that was the plan, shoot for the broad torque curve and not worry so much about the "peak" numbers. If we want to max it out and make it less streetable, a SV intake, 950 carb and 1 3/4 headers would get that 418 over 600hp
And yes I CAN make a 340 with 550hp and still be streetable. Streetable to ME means you can still run your power brakes and Not have to tune it all the time. On the edge, sure but not the ragged edge.