Inside Haisley Machine’s New Billet-Aluminum Block Cummins—And How It Turns Out So Much Power

If you’ve been to a truck pull over the past 15 years you’ve likely noticed an innumerable amount of vehicles wearing a Haisley Machine sticker. There is a reason for this. From Limited Pro Stock to Super Stock, the company has built a name for offering high-horsepower, championship-caliber engines with rock-solid reliability. At the heart of the Haisley name is its owner, Van Haisley, the man who—along with his son, Curt—brought the sleeved and deck-plated 6.7L Cummins to the diesel world. Coined the “Super B,” it was an engine platform that could be campaigned an entire season without the need to worry about anything other than oil changes. Eventually however, the outer limits of what the OEM Cummins block could handle were exceeded.

Like other engine builders, Van turned to an aluminum block for improved strength—but not one that would be outsourced. Starting with a billet-aluminum forging, the crankcase was machined in-house and according to Van’s precise specifications. In development for five years, Van nonchalantly campaigned the new aluminum block in his Super Stock truck, Rock Hard Ram, in 2022. Now, after an entire season of validation—where the engine regularly saw 6,700 rpm and 150-psi of boost—Van’s customers are lining up for the latest and greatest Cummins platform on the market. In a recent visit with Van in the pits, he gave us the lowdown on his new aluminum block program, along with all the other exotic parts that make his Super Stock engine so special.

Retiring The Deck-Plate Super B

Before we had the mega-horsepower machines we have today, Super Stock competitors were running factory, cast-iron blocks—and they lived on the edge with virtually every pass they made. Shortly after the release of the 6.7L Cummins, an engine that came with thicker cylinder walls than the 5.9L thanks to its siamese cylinder bores (and that was readily available vs. the scarce billet block availability at the time), Van decided to make the 6.7L block the foundation for the Haisley Machine Super B program. For added reinforcement, a bedplate was utilized to tie the main caps in with the lower portion of the block and the block’s water jackets were filled with concrete. The block was also machined to accept ductile iron sleeves and fitted with a 1-inch thick deck-plate to limit cylinder bore distortion.

Now that you know that, you should know this. In every Cummins block, there is a horizontal oil passage in very close proximity to the number 2 main bearing. This oil passage is the weakest link within the OEM block and is where most blocks crack due to high-horsepower and excessive cylinder pressure. When Van’s Super B engines began to creep beyond the 3,000hp mark, block failures were beginning to surface. “If you watched your data logger close, you would see a 10-psi drop in oil pressure,” Van told us. “And upon teardown the factory horizontal oil passage across the number 2 main bearing was usually found to be cracked.” Though Van and the Haisley team were able to get by with externally tying the block together, the time to switch to a stronger block was fast-approaching.

Machined from a giant chunk of forged-aluminum, Van’s new billet-aluminum block is void of any internal oil or water passages (the block is fed oil externally), which makes the block significantly stronger than the factory Cummins version. The aluminum block is wider as well, with considerably more meat down the side of the block. Last but not least, Van also designed the block to accept two additional head fasteners. Over-engineered? Maybe. But if 3,500-plus horsepower is to be survived night after night for an entire season and then some, over-building is highly welcomed.

Van Haisley has been an avid diesel truck puller for nearly 40 years now, having gotten his start with a turbocharged 6.2L back in the 1980s. You likely know him best for driving this cut-tire monstrosity in the Super Stock class, although it isn’t the first version of “Rock Hard Ram.” The fiberglass second-gen body sits atop a Barker Machine and Fab tube chassis, and Van has piloted it to countless wins over the years—including at Pulltown USA, the National Farm Machinery Show, and the Scheid Diesel Extravaganza. Here (circa 2012), a cast-iron block, deck-plated Super B Cummins was being campaigned.
In this shot, you can barely make out the billet-aluminum block behind the water-to-air intercooler piping—and that’s if your eyes aren’t drawn to the massive atmosphere turbos or the Sigma pump creeping around on the opposite side. Within the aluminum block, a billet Winberg crank swings six billet rods that benefit from ARP bolts. Forged-aluminum Ross Racing pistons with Total Seal rings bring compression to 12.0:1. For optimum combustion sealing, both the block and head incorporate fire rings.
Haisley’s billet block is made from an aluminum forging from the 6061-T6 family, an aluminum alloy that is precipitation-hardened for added yield strength but that is easy to machine. “The machinability of aluminum is why we went with it,” Van told us. And although this block is lighter than cast-iron, we didn’t go with aluminum for the weight savings.” For reference, one of Haisley’s Super B cast-iron blocks filled with concrete tips the scales at 400 pounds. The solid aluminum block weighs in at 290 pounds.
On top of eliminating the factory oil passage issues with its solid block, Haisley left significant meat on the bone to ensure exceptional strength was on hand. “We added a quarter inch of material on each side of the block vs. stock,” Van said. The increased width lends itself to improved head gasket sealing. The stock cylinder bore spacing was retained, as was the block’s ¾-inch pan rail thickness.
For added holding strength for the head gasket, Van designed the block with a provision for a 27th and 28th head fastener. This was done by incorporating a boss at the front and the rear of the crankcase. And on top of the extra fasteners, 9/16-inch diameter ARP head studs are employed for plenty of clamping force.
It might be a surprise to some, but due to the strength provided by the sheer diameter of a 9/16-inch head stud, ARP 2000 material suffices in this wild, 150-psi of boost environment. With fasteners this beefy there is no need for Custom Age 625+ material like there would be in a 12mm stud diameter, for example.
Up above the aluminum block rests a billet-steel 12-valve cylinder head from Wagler Competition Products. In the Super Stock field, where limitless air is on the table thanks to as many as four turbos being allowed, a done-up, CNC-ported 12-valve head like this remains the weapon of choice. Van’s is graced with an SMT roller rocker assembly, complete with billet steel rocker stands and a one-piece valve cover. Jesel roller lifters ride on a billet-steel camshaft ground to Haisley’s specs, and Van tells us the valvetrain has no problem handling 6,700 rpm.
At the front of the block, a billet front timing gear cover from Keating Machine accommodates a Sigma injection pump. The front cover, which is made from ½-inch thick aluminum, also features an auxiliary drive location for the fuel pump and a -12AN oil port provision which feeds an external catch can.
In the world of mechanically injected Super Stock engines, the Sigma injection pump is the most coveted. But why is that, exactly? Thanks to its use of helix plungers, injection timing advances as rack travel increases. No other plunger-style mechanical pump that we know of does this. And that doesn’t even take into consideration the plunger size, which is 16mm. By comparison, the plungers in a factory Bosch P7100 measure 12mm.
A French company which was eventually bought out by Bosch, Sigma produced a variety of six-cylinder, eight-cylinder, and 12-cylinder injection pumps. The six-cylinder version present on Van’s Cummins is shown here, which is an original, 16mm, cast-aluminum case Sigma. Incredibly, Van told us production for these pumps ended in 1967. Needless to say, they are hard to find. In fact, the last-known region of the world where you could still locate one was South Africa, and it was typically bolted to some type of military equipment.
The 16mm Sigma sends fuel to billet-body, triple-feed injectors from Wimer Fuel Injection & Turbo. The high-flow John Deere-based injectors are designed for Pro Stock tractors and sport 5-hole nozzles, which Wimer produces in-house. This kind of nozzle production capacity has led to major breakthroughs in injector technology in recent years, perhaps most importantly the ability for near-perfect distribution on top of the piston.
To support the Sigma, a Waterman Racing fuel pump is put to work. The gear-driven pump flows a whopping 700-gph. Below it, you’ll find a dry sump oil pump from Peterson Fluid Systems. Van’s 8-stage dry sump oil system provides for 160-to-165-psi worth of oil pressure leaving the line and roughly 130-psi after a hot run. Schaeffer racing oil courses through the Cummins’ external veins.
On top of working closely with Wimer Fuel Injection & Turbo on injector combinations, Van enlisted the Pennsylvania-based company to furnish the engine’s triple turbos. Dual Holset HC5A-based chargers sit out front and act as one giant atmosphere unit in Van’s two-stage arrangement. Identical in size, both HC5A’s make use of billet ball-bearing center sections for utmost durability. Not only do they easily support 3,500 hp (or more), but their size means they enjoy higher rpm (as mentioned, Van has pushed the engine to 6,700 rpm).
Hidden from view is an HX82-based high-pressure turbo, which also comes from Wimer Fuel Injection & Turbo. It too boasts a billet ball-bearing center cartridge. The T6 primary charger hangs from a Steed Speed competition 12-valve exhaust manifold. Also notice the wastegate plumbing. Through external wastegating Van is able to limit peak drive pressure to roughly 135 psi, while peak boost pressure checks in at 145 to 150 psi. This favorable drive-to-boost ratio of less than 1:1 aids both turbocharger and engine longevity.
Sandridge Custom prides itself of producing low volume, high-quality components for truck and tractor pullers—and the performance of its products speak for themselves. The water-to-air intercooler system in Van’s truck revolves around the use of this piece, which cools the twice-boosted, 600-degree F air leaving Van’s turbos down to 100 degrees F prior to entering the head. Dropping air temps this much calls for 100 pounds of ice consumption per hook, as well as the water-injection system kicking in 1.5 gallons of water.
Despite Van assuring us the horsepower output of this new Cummins is “not enough,” we have little doubt it impresses on the engine dyno. But even with obscene levels of horsepower potential you still have to be able to apply it to the track. Despite the benefit of four-wheel drive, the cut tires aboard Rock Hard Ram have their work cut out for them. “On these Super Stock motors, the physical limits on horsepower are our tires on the track,” Van tells us. A full pass might last just 12-to-14 seconds, but with most trucks unable to go full-send until half-track peak power can really only be applied for the last few seconds.
So what do you do when you’re traction-limited, you have to drive your way to a win. More than in any other class, drivers in the Super Stock field have to know their trucks inside and out—and know precisely when to pour on their power. Luckily, because they can’t truly go full-throttle until half-track (or better) most sled operators allow the Super Stock trucks to run out to 330-plus feet, and sometimes even 380 feet, to put on a show. And quite a show it is. If you’ve yet to experience the thrill of a Super Stock storming down the track you’re missing out on the best show on dirt.
As with any brand-new engine programs, Van and team Haisley did have a few growing pains last year. “We had lifter issues early on,” Van tells us. “We ran a 60mm cam instead of a 53mm, and by shoving the lifter further into the block they weren’t getting adequate oil.” After a few ruined roller packs, the problem was solved in-house and Van now pressure-feeds the lifters. This bump in the road was the exact reason for Van’s campaigning the lone billet-block engine in 2022. “I told my customers I’d run mine on kill last year and see what happens,” Van said. With the aforementioned issue addressed, followed by an entire season of trouble-free hooks, you could say the billet Super B is ready for production.
Speaking of being vetted and ready for production, more than a dozen Haisley customers are poised to run the new billet-aluminum block Cummins in 2023. Among the growing list of takers is Carl Butler (Ranch Hand), Jon Bair (Grin-N-Bair-It), Justin Gearhart (Cream Of The Crop), Cody Hastings (Against The Grain, shown), and Jon Woskob (Rollin’ Coal). When we spoke with Van back in November, Haisley Machine was already knee-deep in turning them out. “I have eight more done in the shop at the present time,” he told us. “We also have six more in the works and then we should have another three blocks in our possession by Christmas.”
Time for a 15-year rewind, when figures like 1,300, 1,400, and 1,500 were big horsepower numbers in truck pulling. Some will remember, but many more don’t know that Haisley Machine customer, Shane Kellogg, debuted the deck-plated Super B engine at the 2008 Scheid Diesel Extravaganza. Shane would pull out the win in the Super Stock class—not bad for its first hook! “After that [2008] we realized we needed to modify the girdle to better strengthen the main cap area,” Van told us. Fast-forward to 2022-2023 and the OEM cast-iron block-based, Super B engine program is coming to a close in favor of the billet-aluminum block discussed in this article.

So, What’s The Secret To Making 3,500+ HP?

With the structural and survivability side of the power-making equation figured out (at least for now), Van can focus on finding more—and with any luck, usable—horsepower. According to him, the magic to unlocking more horsepower comes from good cylinder head flow and ever-advancing injector and injection pump technology. “There is no magic in camshafts,” he tells us. “Once you get a cam in the right zip code, you can really only gain 5 hp one way or the other.” On top of cutting-edge cylinder heads and injection components, good airflow via turbos and air temperature are a big part of the power-making puzzle. Van tells us that for every one degree you drop your intake air temps below ambient you gain 10 hp on a Super Stock engine. Needless to say, with the 500-degree drop in intake temps we alluded to earlier, a massive volume of dense, boosted air makes its way into Van’s engine.



Haisley Machine

Keating Machine

Peterson Fluid Systems

Ross Racing Pistons

Sandridge Custom

Wagler Competition Products

Waterman Racing/Aeromotive Inc.

Wimer Fuel Injection & Turbo

Winberg Crankshafts


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