Cummins 4BT Information Archives | Big Bear Engine Company

The Beginner’s Guide To Twin Turbos

By Featured Writer Mike McGlothlin How many of us still call a tissue a Kleenex or have that one relative who refers to every type of soda as a “coke?” We’ve all generalized words in our lives, and in most instances it’s harmless. But within the automotive world—and especially in the diesel realm, where turbochargers…

By Featured Writer: Mike McGlothlin For truck lovers, off-roaders, sled pullers, drag racers, and rat-rod builders alike, there is an undeniable glamor factor associated with a Cummins swap. Whether it’s a 4BT, 6BT, or a late-model common-rail engine, the promise of improved fuel efficiency, endless low-end torque, and million-mile durability is the ultimate selling point.…

How To Test and Service Your Cummins Injectors

By Featured Writer: Mike McGlothlin Despite how durable the mechanical fuel injectors are in the ’89-’02 5.9L Cummins engines, they’re still a wear item. That means that even though this ultra-simple, single-shot injectors are known to last 400,000 miles or more, eventually they’ll need to be serviced. Whether the owner notices a change in performance,…

By Featured Writer: Mike McGlothlin On any internal combustion engine, compression is what makes the world go ‘round. For diesel engines, where compression is often at least double what you see in a typical gasoline engine, it means everything. Not surprisingly, being down on compression means you’re down on power—and that can’t happen when you’ve…

VE Pump Versus P-Pump: Inside The Most Popular 4BT and 6BT Cummins Injection Pumps

By Featured Writer: Mike McGlothlin Distributor style vs. individual plunger, VE pump versus P-pump (P7100). This is a common comparison for anyone new to the 4BT or 6BT Cummins game. The truth is that both engines have employed versions of either Bosch injection pump over the years. As for the 4BT, the VE pump is highly…

4BT Vs. 6BT Cummins: Which Is The Better Swap Candidate?

By Featured Writer: Mike McGlothlin There’s no question that diesel swaps have become commonplace in cars, trucks, and off-road culture in recent years, and the Cummins name is at the top of the most desirable candidates you’ll find. But of the six-cylinder or four-cylinder B-series variety, which mechanical-injection power plant is a better choice? For…

Outer Limits: How Much Horsepower Can You Make With The 4BT Cummins?

By Featured Writer: Mike McGlothlin Thanks to sharing much of its mechanical makeup (and even some of the exact same hard-parts) with its big brother, the 6BT, the 4BT Cummins can support a substantial amount of additional horsepower. Exactly how much remains to be seen, as specific parts combinations vary from application to application. However,…

How (and Why) the 4BT Cummins Is So Popular

By Featured Writer: Mike McGlothlin If it fits, it ships—but if it outperforms, outruns, and outlasts everything else at the same time then it’s probably worth having. We’re referring to the 4BT Cummins, of course. With its packageable dimensions, abundance of low-rpm torque, overland-friendly fuel efficiency, and decades-long durability it’s become a household name in…

What a great end to the week here at Big Bear Engine Company. We just finished up a build cycle of 18x 4BT (3.9 L) and 6BT (5.9 L) Engines. Take a look at a few pictures of the finished product before final packaging.

Skid Steer History and Future Market Share

Skid Steer History Back in 1957, brothers, Cyril and Louis Keller were approached by a local turkey farmer who had a problem. Could they think of a way of a way to get all of the turkey crap out of his barns in a more efficient way than the cumbersome front loader machine that they…

Best Axles for an Off-Roading Jeep Equipped with a 4BT

Let’s talk about axles... If you’re into off-roading in a Jeep you might be pretty much up-to-speed when it comes to axles and which are the best to use - or are you? For the uninformed, all wheeled vehicles have axles and they’re used for steering, driving, and braking, so they’re pretty important. The axles…

The Best Turbocharger for the 4BT and 6BT Engine

When looking at more horsepower and torque for a Cummins 4BT or 6BT Performance mod you are definitely going to want to focus on a larger turbo or setting up a twin turbo situation. For the laymen out there, a turbocharger compresses the air flowing into the diesel engine, squeezing more air into the cylinder,…

Different Types of Motor Mounts One of the last steps before dropping in a Cummins 4BT or 6BT into an automotive swap is making sure the engine fits snugly in-between the motor mounts. Motor mounts act as both a buffer between the engine and the chassis as well as fastening the motor to the vehicle.…

How to Properly Research and Buy a Cummins 4BT Crate Engine

When you’re on the hunt for a Cummins 4BT, the process can be overwhelming. With so many different variants of this engine being produced, a vast amount of information (and opinions) is available about what the best engine is for your particular budget, project and timeframe. The good news is there are options for every…