Electric Fan Conversion (E-Fans)
Applications - Various Cummins, Power Stroke, Duramax
Engine power drawn by the factory mechanical cooling fan is power that can't be transmitted to the tires. Electric fans replace the mechanical cooling fan and are spun by electric motors, not your engine. This allows you to reclaim the energy required to spin a mechanical cooling fan. While a set of e-fans will not help you set any land speed records, the gains are respectable and the additional fuel economy should help pay for the upgrade in the long run. Additionally, e-fans are often an upgrade to your truck's factory cooling system. It's worth noting that this upgrade does not add horsepower/torque to the engine, it simply reduces parasitic loss.
Problems may arise if you don't select fans that are rated to match the cooling requirements your engine demands, especially while towing. Not all e-fans on the market are created equally, so size according to your application. Expect small power increases and noticeable increases in fuel economy. Manufacturers claim up to 30 horsepower.
Kits are available for most Power Stroke, Cummins, and Duramax engines. If you tow a lot during the hot summer months, make sure the fans you select are rated for that. Some "universal" fans will work fine for daily driving, but won't pull enough air to keep a loaded down truck cool. Your best bet is to get an electric fan kit that is designed specifically for your truck and that meets your airflow requirements.
Performance Diesel Injectors
Applications - Most Cummins, Power Stroke, Duramax diesels
Upgraded injectors is where performance can reach new levels. Factory injectors are sufficient up to a certain power limit, at which point they reach their maximum potential. There are a variety of aftermarket injectors available that are optimized to various levels of performance. Enhanced spray patterns, improved atomization, fuel flow rates, and higher injection pressure limits are amongst the makings of a performance oriented injector.
Most injector swaps will require supporting modifications for both protection and to get the most from the upgrade. Depending on the performance level, you'll want to research lift pumps, injection pump modifications, and head studs for your application. You're also likely to see higher EGTs, so large injectors are best matched with a corresponding turbocharger upgrade.
Diesel injectors are measured using one of three common methods, the use of which will vary by application.
• By flow volume in cc (200cc, 250cc, etc).
• By flow volume in LPM (liters per minute; 30 LPM, 40 LPM, etc).
• By the number of holes x size of the holes (6 x 16 = 6 holes @ .016" each).
Applications - Various Cummins, Power Stroke, Duramax
Aftermarket camshafts are a relatively rare upgrade for streetable trucks, but available for many applications. So much power can be revealed with other mods that it makes a camshaft swap seem like a waste of time. However, if you happen to have your engine tore down and are stuffing in performance parts, a new grind can change the manners of your turbodiesel. And if you're interested in going all out for competition reasons, a performance cam is something you should consider.
Since turbodiesels are forced induction engines, they perform best with camshafts that utilize high lift, long lift durations, and very little to no overlap between the power and exhaust strokes. While the OEM camshafts perform adequately, a custom grind may unleash power and broaden the engines power band.
A cam upgrade often requires stiffer valve springs, and if increased lift is desired, machining and/or new pistons may be required. Depending on the the cam profile, some street-ability may be lost. An aggressive cam can greatly improve performance in the mid and upper rpm range, but this often comes at the expensive of torque at the low end, which is obviously preferred for towing and everyday driving. Gains will vary considerably depending on the entire setup, and there are too many variables to predict estimated torque and horsepower improvements, which will range from slight to substantial.
Bosch CP3 Pump Upgrades
Applications - 6.6L Duramax, 2003 to 2007 5.9L Cummins, all 6.7L Cummins
The Bosch CP3 injection pump provides fuel pressure to the common rail on 6.6L Duramax, 2003-2007 5.9L Cummins, & all model year 6.7L Cummins engines. Upgrading the pump for higher rail pressures can increase the power on stock trucks, while highly modified trucks will need to consider CP3 upgrades to maintain fuel pressure under load.
An upgraded CP3 pump can increase common rail pressure, which creates better fuel atomization as it is injected. A high flowing CP3 also maintains fuel pressure on engines with large, aftermarket injectors (performance will suffer on the top end if you can't maintain rail pressure). Additionally, an upgraded pump (or pumps) builds maximum pressure sooner, creating better throttle response and low end performance. For those who want to run extremely large injectors for competition purposes, twin CP3 kits are also available. Using a pair of injection pumps also reduces the load on each individual pump, increasing pump life.
50 to 200 horsepower gains can be expected, depending on how your engine is set up. Manufacturers also claim increased fuel mileage on stock trucks as a result of the improved fuel atomization. CP3 upgrades are applicable to all Duramax engines, 2003-2007 5.9L Cummins, and 2007.5 - present 6.7L Cummins. Running large injectors will almost always require a CP3 pump upgrade in order to get the most from your setup. Contact a dealer to find a pump that fits your needs.
Power Stroke HPOP
Applications - All 7.3L & 6.0L Power Stroke diesels
The 7.3L and 6.0L Power Strokes use a HEUI (hydraulic electronic unit injection) injection system. An HEUI system uses pressurized engine oil to create the fuel pressure necessary for atomization. Oil is pressurized via the HPOP (high pressure oil pump) and routed to the body of each injector. The HPOP can operate at pressures as high 4,000 psi in the 6.0L Power Stroke. The system is significantly different than the standard injection model since fuel is pressurized in the injector body, i.e. there are no high pressure fuel lines. While some scenarios, such as running larger than stock injectors, will require a new HPOP, even stock trucks can benefit from an upgraded unit.
Upgrading the HPOP increases the pumps efficiency, maximum pressure, and oil flow capacity. This translates into higher injection pressures, better fuel atomization, and support for larger injectors. Stock trucks can also benefit from an upgraded pump. If you plan on running larger injectors or aggressive programming on your 7.3L/6.0L Power Stroke, you will benefit from an HPOP upgrade. Manufacturers suggest up to a 100 lb-ft torque increase on tuned trucks. Actual gains will depend on the application and supporting mods.
VP44 Injection Pump Upgrades
Applications - 1998.5 to 2002 MY 5.9L Cummins ISB
The VP44 injection pump is a distributor style radial piston fuel pump. It is found on 1998.5 - 2002 5.9L Cummins diesels. In 2003, the Bosch CP3 pump replaced the VP44 when the Cummins was updated with a common rail injection system. Since more fuel is more power, many companies have engineered upgrade kits for the VP44 so that it can provide enough fuel pressure/volume to support significantly more horsepower. If you are looking for big numbers from your 98-02 24v Cummins, you may consider upgrading the pump for additional fuel pressure & flow.
Increasing fuel pressure improves atomization, a key ingredient to performance and fuel economy. An upgraded VP44 also has a higher flow capacity, meaning that it can keep up with larger injectors and tuning. Expect an upgraded to pump to be re-manufactured (so that it is "like new"), re-calibrated, and have a larger head unit. Parts are available to upgrade the pump on your own, but we'd highly recommend that the pump only be disassembled, rebuilt, and modified by a qualified technician. Expect to pay a hefty core charge when upgrading, as this is what keeps the market moving.
Failure to install a high flow lift pump (FASS, AirDog, etc) may result in premature pump failure. Rear wheel gains for most upgraded VP44s are in the 50 - 100 horsepower range and up to 270 lb-ft of torque. As with all upgrades, actual gains may vary considerably.