Under Pressure: Extreme Injection Pumps
As the heart of any diesel’s power-making puzzle, the injection pump can never be overlooked. Whether you’re talking mechanical P-pumps, high-pressure common-rail pumps or even HEUI pumps, they’re all the vital middle man in a system that relies on highly-pressurized fuel in order for the engine to work its compression-ignition magic. Increase that pressure and you add power. Increase both volume and pressure and you make really big power. In the far corner of diesel motorsports—where the 2,000 to 3,000hp engines live—injection pumps can get pretty wild. Everything from highly modified factory-based pumps to exotic units machined from a solid chunk of billet-aluminum are employed, along with multiple high-pressure pumps being the norm on high performance common-rail Cummins, Duramax and Power Stroke mills.
Below, we’ll give you a taste of the baddest of the bad in diesel injection technology. From the infamous mechanical “Sigma” pump to the multi-CP3 combinations that’ve made 2,500hp common-rail engines possible, the following technology is what’s bolted to the top sled pullers and fastest drag racers in North America.
Mechanical Pumps
The “Sigma”
Also known as the $10,000 injection pump, the Sigma pump is a plunger-style, inline mechanical pump similar in design to the Bosch P7100 found on the 5.9L Cummins that powered Dodge Ram 2500s and 3500s from ’94-’98. However, instead of making use of 12mm plungers (what you’d find in a Bosch P7100), the Sigma came with 16mm plungers right from the factory. These massive plungers facilitate a much quicker injection rate (i.e. more fuel being injected quicker), which leads to better engine efficiency and, ultimately, horsepower. Although truck pullers have been using Sigmas for more than a decade, breakthroughs in billet engine blocks, head-flow, camshafts and turbo technology in recent years has allowed more of their fueling capabilities to be realized. This factory, cast-aluminum 16mm Sigma offered by Columbus Diesel Supply can flow up to 1,600 cc of fuel, although most engine combinations start out using 950 to 1,100 cc. To put things into perspective, per Bosch Motorsport, a stock Bosch P7100 with 12mm plungers flows just 135 cc.
The Billet Mack Daddy
Columbus Diesel Supply’s 17mm billet Sigma pump is the big daddy of the injection pump world. The pump body is machined from high density billet-aluminum and incorporates 17mm plungers, a special grind camshaft and other proprietary internals (such as delivery valves and holders, control sleeves, pump vent and governor, among other components). Matched with the right injectors (typically triple-feed designs and International or John Deere based) and airflow (big single or two-stage turbo arrangements), a 17mm Sigma can support in excess of 3,000hp. While the 16mm version of the Sigma can be found in some drag racing applications as well as on a lot of Super Stock pulling trucks, the tractor world is where you’re most likely to spot one of these billet 17mm bad boys hanging off the side of an engine. Let’s just say you know it when you see it.
Scheid Diesel 14mm & 16mm P8600s
Scheid Diesel is also in the business of building competition-ready P-pumps. The Bosch P8600-based pump shown above enables the company’s record-setting Cummins-powered dragster to pump out 2,500hp and run six-second quarter-miles at more than 220 mph. Also widely used in Pro Stock pulling trucks, its highlights include 14mm plungers and barrels, a custom grind cam and an adjustable timing gear. All vital moving internals are coated with a friction reducer for smooth operation and optimum durability and—depending on the application—the pump can be configured with an RSV (“Ag”) governor that allows full fueling up to 7,000 rpm! Scheid’s 14mm pump flows a maximum of 1,100 cc, but if that’s not enough Scheid also offers a 16mm version, which is rumored to be capable of flowing more than 1,500 cc.
12-Cylinder Pumps
When one plunger per cylinder isn’t enough, there’s always a 12-cylinder P-pump! Originally used on Deutz 12-cylinder F12L714 engines, a few modified versions of these pumps were in use along the truck pulling circuit roughly a decade ago. Requiring two injection lines per injector, they were known to deliver torrents of fuel in an extremely short duration and make some pretty good power. However, they proved to be fairly temperamental (we’re told stuck plungers were a common issue) and, ultimately, technological breakthroughs in single plunger pumps ended up killing them off.
13mm P7100s
Capable of supporting in excess of 1,400hp, P7100-based pumps that utilize 13mm plungers and barrels are hot-ticket items both at the drag strip and in Limited Pro Stock pulling classes. Occasionally, you can even find them on some freakishly-fast street trucks. Even though it was feeding a highly abused, 250,000-mile 12-valve 5.9L Cummins, the 13mm pump pictured above still supported a 1,237rwhp, 2,114 lb-ft effort on the chassis dyno.
Common-Rail Pumps
Quintuple CP3 Duramax: 2,570HP (Fuel)
While the old game of utilizing huge injectors to make big horsepower is the same between mechanical and common-rail injection, today’s high-tech common-rails require multiple high-pressure pumps in order to make it happen (1,200hp+). In the case of Wes Kusilek’s Super Stock Duramax, the engine’s injectors are so big that five modified Bosch CP3s are needed to maintain rail pressure. On the engine dyno—and in conjunction with a 5.25-inch inducer Pro Stock tractor turbo from Columbus Diesel Supply feeding boost into the Wagler Competition Products DX460 Duramax—the one-off, five-pump CP3 arrangement provided for 2,570hp to be produced at 4,900 rpm (and 2,854 lb-ft of torque at 4,600 rpm).
Triple CP3 Cummins: 2,571RWHP (Nitrous)
In order to get nearly 2,600 hp to the wheels, it takes some serious fueling, a whole lot of air and in Shawn Baca’s case, an extra kick via N2O—even though his ’06 Dodge Ram has cleared an insane 2,375rwhp on fuel alone in the past. While the triple XP CP3s from Industrial Injection seem to have no problem keeping up with a set of injectors that are likely somewhere between 500 and 800-percent over stock, the engine is being fed air via a massive two-into-one triple turbo arrangement composed of three 106mm chargers. With turbos sized this big, it takes considerable engine rpm to keep them in their happy place. As a result, Baca’s deck-plated, 6.7L Cummins-based engine regularly sees 5,000 rpm. To keep the CP3s from overspeeding, they’re underdriven via massive pulleys from Beans Diesel Performance.
Triple CP3 Duramax: 1,680HP (Fuel)
In the photo above, you’re looking at a billet-aluminum triple CP3 gear drive bolted to a marine Duramax engine put together by Wagler Competition Products. On the engine dyno, and thanks to a set of 250-percent over injectors, the aforementioned triple-CP3 configuration, a Bosch stand-alone ECM, a 98mm turbo from Precision Turbo & Engine and Wagler’s done-up cylinder heads and water-to-air intercooler intercooler, the engine cleared 1,680hp and 2,400 lb-ft of torque. For utmost durability at this power level, a brand-new LML block was used (the strongest Duramax block ever cast by GM), along with an internally balanced billet crankshaft, competition girdle, billet main caps, steel connecting rods, forged pistons and a dry sump oil system.
Dual CP3 Duramax: 1,600HP at the wheels
Thanks to combining the forces of two 12mm stroker CP3 pumps with a set of 250-percent over injectors (along with a triple-turbo arrangement), the LB7-powered crew cab GMC Sierra owned and driven by Mike Graves of Hollyrock Customs has blasted through the quarter-mile in 9.55 seconds at 149 mph. At 7,000 pounds and that trap speed, his full interior ¾-ton is sending at least 1,600hp to the ground. What’s even more is that the high-powered, dual CP3-equipped GMC is backed up by a Limitless Diesel Performance-built Allison 1000 transmission and not a 47/48 swap.
High-Pressure Oil Pumps
Dual HPOP 6.0L Power Stroke: 1,870HP (Fuel)
Exotic injection components aren’t reserved solely for mechanical or common-rail systems, as this dual high-pressure oil pump arrangement on a HEUI-fired 6.0L Power Stroke shows (HEUI standing for hydraulically activated electronically controlled unit injector). Adding a belt-driven HPOP to the equation has paid big dividends for extreme 6.0L builder and avid competitor Jesse Warren of Warren Diesel Injection. This engine, equipped with a sizeable compound turbo configuration and a set of proprietary 760 cc injectors, has pushed the HEUI platform close to 1,900hp on the engine dyno.
