http://www.stangtv.com/features/pri-...d-new-z2-head/

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At this year’s Performance Racing Industry show, Ford Racing was showing off something that many 4.6 fans will be very interested in. An all new 5.3 crate short-block, that is based on the 4.6 architecture, and is compatible with two, three (SOHC), and four-valve (DOHC) 4.6-liter heads.
The engine features a solid and proven foundation, and according to Ford Racing’s Mike Delahanty, is ready for just about anything. “If you want the biggest possible modular 4.6 based engine you can build, whether you want to go NA, power adder, or go crazy, this is it. The idea is you can use this as the foundation to build an engine for anything from a mild cruiser, up to something that can go racing.”
•Built from all new parts, not remanufactured
•Based on BOSS 5.0 modular block (4.6 architecture)
•94 mm bore
•5.3-liter displacement
•Eagle forged H-beam rods
•Eagle forged stroker crank
•MAHLE forged pistons with three-valve cylinder head compatible valve relief
•Compatible with two, three, or four valve 4.6 heads, including Trick Flow
•Compression ranges from 9:1 to over 10:1 depending upon cylinder heads
This engine takes the hassle out of getting a properly machined, and built 4.6 liter based engine, and is a solid foundation for a variety of builds, capable of taking just about whatever you can throw at it. “We’ve done the hardest parts, machining the block, bearing clearances, etc. The buyers get to do the fun parts,” said Delahanty.
We can see this in a variety of street and racing project cars in the very near future. Ford Racing’s Jesse Kershaw says that this engine should be available late in the first quarter, or early second quarter of 2015, pricing details haven’t been released yet