If you're like us, you've looked at quite a few gasoline- powered rides and thought "that thing would be so much cooler, if it had a diesel in it!" Well, we're here to tell you that it can be done. Diesel engine swaps are becoming more and more common, and while we're starting to see more Power Stroke and Duramax conversions, by far the popular engine of choice is the B-series Cummins.
There are many advantages to swapping an '89 to '98 1/2 5.9L 12-valve Cummins engine into your vehicle. They're everywhere, so they're a cheap engine to buy (especially the '89 to '93 VE-pump versions-although the '94 to '98 1/2 models can produce more power) and parts are easy to find. They're also utterly simple. While newer computer-controlled diesels require multiple computers and a bird's nest of wiring to make them perform properly, the older mechanical engines require two, maybe three wires to make them run. They also have an almost unlimited horsepower potential, a strong aftermarket backing, and a variety of transmission choices.
6BT VS 4BT
Sometimes there are situations where a six-cylinder Cummins 12-valve just won't fit. If you're looking to perform a Cummins swap on a Jeep, small pickup, or a car, the 5.9L engine will probably be too long, too tall, and too heavy. But there is hope. Cummins also made a 3.9L four-cylinder version of the 12-valve called the 4BT. This engine has the advantage of being much shorter, and about 300 pounds lighter than it's bigger brother. The most common applications for these engines were 1-ton bread vans, and box-style delivery trucks.
Fitting The Cummins
OK, so while you're searching for either a four- or six-cylinder Cummins, it's time to think about all the other aspects of getting the diesel engine to fit. The six-cylinder version weighs in at about 1,100 pounds, and is 35x23x31 inches (length x width x height-not including the turbo), while the 3.9L four-cylinder weighs in at about 800 pounds, and is 30x23x31 inches. To simplify matters, we've split this section up into different aspects of the build you'd need to concentrate on.