Before the diesel enthusiast mantra was “Cummins swap the world”, the Perkins diesel engine was the engine of choice. In case you’re not familiar with the Perkins engine, F. Perkins Limited was established in June of 1932. The company’s first diesel engine was the four-cylinder Vixen, which made its debut that year. In October 1935, Perkins became the first company to hold six diesel speed world records. Sales were strong and, by the time of World War II, the company made two series of engines, the P4 and P6. Fast forward to 1998, and Perkins becomes a subsidiary of Caterpillar. The rest is history.
The reason I mention the Perkins engine is because the 1941 Dodge WD21 we are featuring today is powered by a 1963 six-cylinder Perkins diesel displacing 354 cubic inches. That in itself is cool, but add on the compound turbos, custom exhaust manifold, and a maximum boost of 14 psi, and it is off-the-charts cool.
“The diesel was naturally aspirated until I put the first turbo on,” quips truck owner, Paul Lasota. “Then one day, a good buddy of mine walked up to me with a turbo in his hands and said, ‘you know what you need to do with this’, so now there are two.”
It’s What’s Underneath That Counts
According to Paul, “the truck is a 1941 one-ton WD21. It’s a California truck that came from the factory with dual wheels and a flatbed. As you can see, it has been heavily modified. It still sits on the original ‘41 frame and uses the factory front axle. The Cab and front end sheetmetal are original.”
Paul says the previous owner built the custom box, but the rest of the design and fabrication was done by him. “I purchased the truck in 1985, but I never had time to do a lot of work to it. Between family and work obligations, it has only been during the last ten years that I really went to town on it.”
The engine is coupled to a Silver Sport Transmission’s (SST) TREMEC TKX five-speed, and the differential is a Dana 60. The combination has hit the dyno and delivers 90 horsepower and 360 lb-ft of torque at the rear wheels.
This is a truck, and as such one would expect a heavy-duty leaf spring suspension. Not quite. Underneath is a front and rear four-link suspension with airbags. Steering duty is handled via GM Power steering through a late-model steering box, with hydroboosted power brakes. Clamping force is applied by Wilwood twin-piston front calipers on the front and Ford drum brakes on the rear.
“The four-link and the airbags make the drive a lot more comfortable, the original suspension was like driving with no suspension. I almost needed a kidney belt for long drives,” Paul says.
Grab Another Gear
When asked why a TREMEC TKX transmission, Paul has this to say, “I did start searching around for what I could put in the truck for a standard transmission, and I could not really find anything that would work the way I wanted. Then I talked to Gene at SST one day about it. He was hesitant at first because of the Perkins diesel, as SST doesn’t have a bell housing to match it. It took some convincing, but I did explain that I currently had a small-block Chrysler 727 bolted to the Perkins with an adapter plate for the transmission and torque converted, so the SST Chrysler kit should work, he did finally agree.
“The first thing I did when I got the SST kit was test fit the bell housing and flywheel. I was happy they both fit. I was off to a good start. There were some challenges fitting it all in the truck, but at no time did I ever have the feeling that this is not going to work. I did have to modify a crossmember, make a new rear transmission mount, build a remote shifter and get a new driveshaft. The trickiest part was making the remote shifter. That took some serious thought and some consulting with a couple of good friends of mine. The original shifter position came up in the middle of my seat, not so good.”
When asked why he decided to build this truck, Paul has this to say, “the only thing I can come up with is, just for the fun of it. I have never done a build like this and everything had to be designed from scratch, so it challenged me. The truck is unique, and I will admit that I love the attention it gets at shows.”
Let’s See Yours
Do you want to see more Reader’s Rigs? Well, so do I. If you would like to share yours, I want to hear about it — I can never get enough. And if you want to see more trucks built by you the readers, click here. Finally, if you want to see your rig here, send a few pictures of your rig showing the engine, interior, and exterior, along with all of the pertinent information, and I’ll make you internet famous. You can send your submissions to [email protected].