With a fairly compact combustion...
With a fairly compact combustion chamber, the pistons didn't require much of a dish to hit 11.3:1 compression, even with the mighty 4.25-inch stroker crank.
Operating the modified lifters is a custom COMP camshaft that was ground with an eye on increasing cylinder pressure and closing the intake valve quickly-to fool the engine into thinking it has more compression than it really has. "Typically on stock and street high-performance stuff, these things run the cams really retarded. They run them at about 120 degrees lobe separation. Unfortunately, for the contest, the tightest lobe separation cam core we could get was 108. We would have liked to get a cam even tighter than that, so we only tried one cam. I suspect there could be more score there. To make a cam like we wanted, we would have had to buy a core out of round stock, and it's about a six-week wait period and about a thousand dollars." BES said they have tried different cams in their street engines but they tend to be milder since the factory ECU doesn't care for anything too radical. Fortunately in this case the team had an ACCEL DFI system, and team member Richard Kolb was there to tune it.
BES has run the DFI system in the past and has been extremely pleased and comfortable with it. The operation of DFI begins with a crank position signal provided by an MSD flying-magnet crank trigger. The signal is received by a VR (variable reluctance) pickup, but DFI also has the option of using a Hall effect sensor as a trigger. Baseline tables generated by inputting the basic engine design (including cubic inches, ignition system type, batch or sequentially fired injectors, rpm range) are then used to get the engine up and running. Wideband oxygen sensors then allowed Kolb to monitor the engine's performance and adjust the tables for maximum performance in real time. Rockett Brand 91-octane unleaded gas was then sent through 46 lb/hr injectors to get burned in the chambers.
Team members John Lahone,...
Team members John Lahone, Tony Bischoff, Richard Kolb, and Brad Nagle stand proudly with their creation minutes after being crowned the Engine Masters!
The job of burning the gas fell to a custom dual ignition system built with ICE Ignition components and put together by BES team member Brad Nagel. Since the Hemi is designed for dual spark plugs and the crew wanted to use the high-output 10-amp ICE system, they constructed a system using two distributor bodies mounted on a common shaft and driven by a belt coming off the camshaft. Innovative? You bet. Tricky to build? Definitely. But BES is known for thinking outside the box.
It is that outside-the-box thinking that has lead BES engines to absolutely dominate the NMCA ranks and being a multitime winner of the Engine Masters Challenge. Bischoff and his team have proven once again that when thrown into any kind of race, they have mo' skill and mo' knowledge, and their engines definitely make mo' power.
You can see the beefy cross-bolted...
You can see the beefy cross-bolted mains with ARP main studs clamping the bearings in place. The old truck crank shed almost 10 pounds on its way to a new, more aerodynamic design.
Not an off-the-shelf part....
Not an off-the-shelf part. With one dizzy running clockwise and the other counterclockwise it was a simple matter of reversing the firing order on the cap and routing the wires correctly to make it run. Maybe not so simple, since they had to cut the distributors up, make a common rotating shaft, build a bracket system, and phase them together so they would actually be in sync.
The new Hemi blocks are as...
The new Hemi blocks are as stout as they have historically been, and are built for abuse. Aiding in controlling the forces trying to rip them apart, the late-model Hemis are all internally balanced. The standoff pipes shown are actually oil drain tubes Bischoff installed to drain oil way down south, avoiding windage.
The K1 H-beam rods are top...
The K1 H-beam rods are top quality and though they look thin, are more than capable of handling the 700 horses the engine produces. The Ross piston forging was also compact and light, yet incredibly stable under load.