High Roller's FE
By Bob McClurg
*Reprinted from Ford High Performance June 1998

Perhaps the title of this piece might be a bit misleading. Believe it or not, Carroll Shelby's all-aluminum, 427-428 style, Medium Riser engine block (released in the winter of 1997) wasn't built with huge profits or volume sales as its primary objectives. Rather, it was built out of sheer necessity.

True, Shelby's 427-428 FE re-pops do specs out at a rather pricey $5,000 a piece (Old Shel has sold close to 50 blocks now), while his aluminum alloy 427 Medium Riser cylinder heads (introduced in late 1995) retail for around $1,850 a set. Neither is exactly what you would call inexpensive in this day and age of mass-produced, high performance engine hardware. But then, when you have problems keeping either item on the shelf (and have a sizeable customer back order list to boo), you evidently must be doing something right.

Sound Logic, Behing an Even
Sounder Product
"The reason we built these parts is because cast iron 427 FE engine blocks and good cylinder heads were becoming difficult to obtain," says Shelby Enterprises FE engine project director Mike Le Fevers. "At the inception of Carroll's "Cobra Continuation Series" program, we located a few new/old stock (N.O.S.) cast iron 427 FE block still required approximately $1,000 to $1,200 dollars worth of finish machine work. By the time we were ready to assemble a stock stroke 427 FE short-block, we had approximately $5,000 invested."

A Beauty Of A Big-Block
From the outside, these blocks look for all the world like any other FE, albeit all done up in nice, shiny aluminum. The reality of coarse is that other than being dimensionally the same from the outside, as well as sharing basic FE engine hardware (i.e.: cranks, pistons, rods, bearings, cams/valve train components), the "CS" inscribed aluminum alloy FE block is entirely another "animal."

One of the most noticeable differences are the three main "ribs," which are an inherent design feature on the most, if not all, aluminum alloy aftermarket performance V-8 engines like a Keith Black, Donovan, JP-1, Rodeck, or Arias. These ribs not only shore up the top end of the engine (providing extra rigidly to the cam and lifter valley areas), they also effectively help control block stress or warpage from extreme heat buildup.

BADDER THAN BAD
As a part of Shelby Enterprises ongoing R&D program. Carroll Shelby dictated that this block be taken to the limit, and quite possibly beyond. As such, Le Fevers and company have embarked on a "Monster FE" engine-building program following Shelby's dictates. Would you believe a 526-cubic-inch, all-aluminum FE? Well, believe it!

"What we have done is bore the block out itself, and installed a larger diameter sleeve." Le Fevers went on to explain that the bore centers on a standard-bore 427 measure 4.630 inches. They have bored this block to accept a sleeve size of 4.625 inches (leaving .002 inches between the cylinders), and that's big! "You're lucky if you could slide a piece of tin foil between the bores," laughs Mike. "What we're doing is verifying the integrity of this block by conducting this program."