A Dart block provides a bulletproof...
A Dart block provides a bulletproof foundation for this radical Ford small-block. The block’s massive main structure secures a 4.00-inch stroke Eagle crankshaft riding on Clevite bearings. Note the contoured profile of the Eagle crank’s counterweights to reduce windage. Rods are Eagle 6.125-inch H-beams.
Tony Bischoff and BES Racing Engines are names familiar to those who follow our annual Engine Masters Challenge engine building competition. Bischoff and his expert crew at BES Racing Engines have come to the competition since 2003, and in the process earned the championship no fewer than four times. Coming into the 2011 AMSOIL Engine Masters Challenge, the recent changes to the competition format seemed to be tailor-made for an organization like BES Racing. For the first time the competition was divided into two categories: Street and Xtreme Street. The build rules for the Xtreme class presented the opportunity for competitors to really bring on the heavy-hitting hardware and make serious power. Making serious power happens to be just what BES Racing does best.
The wild 441-cube Ford small-block examined here was BES Racing’s weapon of choice, and judging from the 913 peak horsepower produced, it proved to be as effective as it was deadly to the competition. For Bischoff and crew, it was all in a day’s work, since this is the very type of engine the shop builds on a routine basis. Bischoff tells us: “We build a lot of these engines using that particular cylinder head. It’s a good combination for us and I thought it would do well in the contest.” Of course, building it for the competition required a unique development process, though the basic parts combination relied on components that were well proven.
The Ross Pistons feature an...
The Ross Pistons feature an inboard pin boss that helps create a very rigid piston skirt, providing a big advantage with short compression heights. The design also allows for a much shorter piston pin, which reduces weight.
Bottom End Beef
The build started with a Dart block with the bore size machined to 4.180 inches, and other than the basic machining prep and bushing the lifter bores for .904-inch lifters, there was little to do here. Dart’s block comes with all the beef and strength needed for reliability at high power levels, with revised oiling and a massive bottom end structure. For Bischoff, it is the right choice when targeting high power output. A 4.00-inch Eagle 4340 crank with Eagle’s Armor Coating fills the crankcase, providing a displacement of 441 ci. The crankshaft was indexed at BES Racing, and other than a minor detailing it was used without modification. Eagle was also the source for the connecting rods, with Bischoff selecting their lightweight 6.125-inch H-beam rods, which were also treated to Eagle’s Armor Coating process.
BES Racing selected a set...
BES Racing selected a set of Total Seal rings in a .043/.043/3mm configuration. The ring set includes Total Seal’s unique Gapless Top rings, resulting in what Tony Bischoff tells us is one of the best compression-sealing engines he has ever built. The second ring features a Napier face profile to aid in oil control.
Filling the bores is a set of Ross pistons, which feature the modern inboard pin boss design. As Bischoff tells us, the major advantage here is strength: “These really work well with the short compression height stuff. They have a rigid skirt and pin boss, because they put those support struts in there. They seem to make more power because they are that much more rigid.” The pistons were cut for a .043/.043/3mm ring package, and Bischoff opted to go with a set of Total Seal rings. The ring set featured a gapless top ring, a configuration that Bischoff has not used frequently in the past, but as he tells us, the results were impressive. Bischoff relates: “It was the best sealed motor I have ever built.” To complement the top ring, the Total Seal second ring featured a Napier-style face, which definitely improved oil control.
With the small dish pistons, the final compression ratio worked out to 14.5:1, though Bischoff believes the engine would have benefited from even more: “I think we left a little on the table with the compression ratio, and the engine could have made a little more power with more compression. The ratio was just left where we started at, and I was happy enough with the numbers when we dyno’d it that we just left it there.” We questioned Bischoff further about where he sees the point of diminishing returns with compression ratios on this type of engine. He explained: “On the dyno, with the kind of octane fuel we were running [VP Racing Fuel Q-16], typically you will see the power keep increasing right up to 17:1, however, on the racetrack it may not show up because most of the time you can’t control the temperatures as well, and the cylinder-to-cylinder variations can get further off. So, it may not run any better down the racetrack with that much compression, but it will dyno better.”
The block was bushed in the...
The block was bushed in the lifter bores for a set of Jesel .904-inch roller lifters, and fitted with oil drain standpipes. In fact, there was very little oil entering the lifter valley due to external drain back from the cylinder heads.
Roller cam bearings for a...
Roller cam bearings for a 55mm journal were fitted to the cam tunnel, allowing a large-journal custom roller cam to be used. The large journal allows for a much more rigid camshaft, reducing deflection and torsional twist for more accurate valve motion. The larger lobes also provide a smoother profile.
To save weight with the long...
To save weight with the long valves used by these Edelbrock heads, Bischoff went with Victory titanium valves measuring 2.250 (intake) and 1.600 (exhaust) inches.
The custom COMP roller delivers...
The custom COMP roller delivers a moderate 252/262 degrees duration at .050, however, working with a monstrous rocker ratio of 2.0/2.08:1 the valve lift is a lofty .940 inch. The cam was ground on a lobe separation angle of 112 degrees and was installed on a 107-degree intake centerline.
BES Racing sized the CNC ports...
BES Racing sized the CNC ports specifically for this application. The modified port profile was simply done as a variation of their standard drag racing port design on the Rottler CNC software. Note the offset in intake port position relative to the O-rings, resulting from skewing the ports outward for a straighter shot from the intake manifold.
The cylinder heads were the...
The cylinder heads were the key to making the kind of power this engine delivered. The Edelbrock Glidden SC-1 heads are a true race casting, with tremendous flow potential. CNC ported by BES Racing, the heads deliver a peak of 440 cfm intake, and 300 cfm exhaust.