It always comes down to the individual and what you want, what you can afford and what's available. To me the 60s style engine built with todays products is what is desired by me. With that said their are a bunch of new engines that would be cool in a Cobra. Ford's new 5.0 is 430 HP right out of the box and if you look on YouTube some have already made it look and sound like and engine of the 60s with the quality, fuel economy and durability of 2010. Ford makes a bolt on supercharger with warranty that takes it to 600HP+. I'm a bit old school and just had a Keith Craft build me a all aluminum 496 FE (681HP) for my new Cobra. The cool things about Cobras....make it your project and what you desire in a Cobra...bottom line..they all are cool!