Seems Ford is set to release a new 5L engine for the Mustangs in 2011.
Alloy including block, 4 valves per cylinder, developing a claimed 412 HP with variable valve timing and capable of spinning to 7K - sounds like a nice package.
Not sure on the engines dimensions but its got to be smaller than the current 5.4L crop of motors.
Perhaps a crate motor option for those now in research mode.
Article and pics below, as found on FFR site -
http://www.windingroad.com/articles/...ter-v-8-power/
Cheers