745kW diesel-powered hot rod truck aims for 300km/h
It all started 12 years ago, this business of reaching 300km/h in a 5-tonne truck called Diesel & Dust, and setting a new world speed record with a naked lady perched on top of the radiator.
A friend called Tshwane business owner Henk Vryenhoek with news of a 1,000hp (745kW) Detroit D90 V12 engine. The 18.1l two-stroke diesel engine hailed from a dump truck and comes standard with two huge turbochargers and two superchargers. Besides the 1,000 horses, peaking at 2,700rpm, about 3,700Nm of torque is also on tap.
Just the ticket then if you want to go ridiculously fast in a truck. And Vryenhoek had a number of land speed records in his sights.
“I bought the engine and started looking for the ideal donor body, chassis and gearbox. I eventually got hold of a 1966 Kenworth D900 chassis and cab,” he says.
Next Vryenhoek, a long-time car collector and customiser, acquired an Allison 6000 Series six-speed automatic gearbox, which was salvaged from a bus.
The two huge, old-school turbochargers, hailing from the 1980s and making do without modern tricks such as variable vane technology, take their merry time to start spinning, so the truck is not suited for quarter-mile runs.
Too high
A fire appliance’s high-speed rear differential was added, as was a Kenworth air braking system, with drums at all the corners. The 20-inch Bridgestone truck tyres were the tyres with the highest speed rating Vryenhoek could source (120km/h). For the actual speed record runs, the rig will be fitted with Boeing 747 Dunlop aircraft tyres.
The team still faced a major challenge with all the parts sourced: if they ran a traditional suspension set-up, the truck would sit too high off the ground. And that’s not ideal if you are barrelling along at 300km/h.
So the truck was chopped and zeed — customiser jargon for mounting the body over the chassis beams, not on top of it. And the Kenworth cabin was chopped by 150mm.
“The speed record was always the main aim, but I also wanted to give it a unique styling finish. The designs of my cars are heavily influenced by aircraft paraphernalia, so I envisaged a truck version of a Model T hot rod, with some aircraft bits added. So we included authentic rocket launchers from an Impala fighter plane on the sides, a collection of four fuel drop tanks at the back and a four-point aircraft seat-belt system for the cabin,” says Vryenhoek.
The team aimed to have the truck finished for the Cars in the Park exhibition in August 2013, working through the night. But tragedy struck the night before Diesel & Dust would make its debut and run for the first time: team member Charles Terry suffered a fatal heart attack.
“It was a very tough day for us,” Vryenhoek says. “Charles played a pivotal role in this project. Together with craftsman Con van der Kolf and welder Liep Bronkhorst, with the support from my entire team at Gigantic Earthmoving, this dream was turned into a reality. Losing Charles was a heavy blow, but we carried on regardless, in his memory.”
The next stop would have been the 2016 Speed Week meeting at Hakskeen Pan, Northern Cape, in preparation for the attempt at the speed records. But the event was cancelled, and Diesel & Dust has since been unable to run at high speeds.
That is set to change in 2020, with Diesel & Dust scheduled to have a crack at the SA speed record for trucks in September, with a target speed of 192km/h. Vryenhoek will pilot the truck for this run.
“If all goes according to plan, we’ll have a crack at the 200mp/h [320km/h] barrier in the first half of 2021, with a professional driver behind the wheel,” says Vryenhoek.
For that run Diesel & Dust will have those Boeing 747 tyres, as well as a parachute system to help the 5-tonne machine slow down after the high-speed runs. The gearbox ratios will be changed to allow for that higher top end.
“We are running our project, which is 100% self-funded because we want to do things our way and not the sponsors’ way, in conjunction with the Bloodhound world speed record attempt.
“We’re obviously not in the same league as Bloodhound or competing with them ... they are aiming for 1,600km/h and they’ve spent vast amounts of resources and money to achieve this. For us it’s more a case of our shared passion for automobiles and engines and speed, in support of this momentous occasion,” says Vryenhoek.
As is often the case with such projects, it’s a work in progress. The huge turning circle would make an oil tanker giggle uncontrollably, so the chassis will soon be shortened by a metre. A more aerodynamic, custom-made rear panel will fit over the back section, vastly improving airflow at high speeds. Specialised aeronautical rivets are also on order to further improve airflow.
Then there’s the curious case of the naked lady mascot perched on the radiator. Rolls-Royces are adorned with the famous Spirit of Ecstasy ornament sculpture on the bonnet; Jaguar has a leaping cat.
“It doesn’t represent any specific brand like the Spirit of Ecstasy does. She doesn’t have a specific name either. I just liked her proportions, and her pose seemed spot on for Diesel & Dust. In the sixties, when the truck was originally made, bonnet ornaments were a big fashion statement, so it’s kind of an essential finishing touch,” Vryenhoek says.
That’s Diesel & Dust. A 1,000hp hot truck that looks like it was driven straight off a Mad Max movie set.