SCORE Journal - The Official Publication of SCORE Off-Road Racing
Issue link: http://read.uberflip.com/i/631836
powerful engine, so using the HR35TT made perfect sense." Well, maybe. Turbocharging remains a rarity in off-road racing. The comparative complexity of the plumbing for a turbo system versus virtually none for a naturally aspirated engine makes its implementation less than ideal for most teams – and you certainly don't want any of that plumbing to shake loose during a jump or over rocks. The smooth asphalt ovals at Indianapolis and Daytona are worlds away from Baja. And then there's the heat to deal with. "Heat management was the biggest challenge in the Ridgeline race truck," says Proctor. "The turbos make a lot of heat and we had to design some very specific airflow solutions to make sure the system kept its cool." Those solutions included running a front-mounted radiator and a hood scoop for system's intercooling heat exchangers. The truck also featured a rear-mounted carbon fiber scoop to hold the rest of the component coolers, while the tinwork inside the front fenders included mesh to enable even greater cooling airflow to the engine compartment. For the record, the engine uses a pair of BorgWarner Turbo Systems electronically actuated turbochargers. Boost levels – the amount of pressurized air the turbos generate and force into the engine to enhance horsepower – will vary among races, but around 8 psi was the max for running in the SCORE Baja 1000. "It wasn't as much boost as many might assume, which helped with heat management, but it was more than enough to really make the truck fly," says Proctor. "As a matter of fact, our data showed the engine often ran below the expected thermal levels during many sections of the race, while performing as expected under sustained periods of boost. The heat management system was designed for it." Honda Performance Development naturally had a stake in the Ridgeline's success at Baja and, led by engineer Matt Niles, supported it with a three- member chase team during the race. Before that, extensive testing was conducted by Honda and Proctor's team, because the dirt, dust, silt and other off-road elements were never considered when the HR35TT was originally designed. "It's hard to describe how well the engine pulls," said Proctor. "It is calibrated to deliver the power where it's needed the most, which means we don't have to alter our driving style to accommodate turbo lag or anything like that." While there was plenty of time with the engine itself, precious little time had been spent in the completed race truck before the SCORE Baja 1000 started. "We only had about 150 test miles on it before rolling up to the starting line," says Proctor. "There were many people who thought a turbo truck was questionable in such a tough race and we were about to confirm or shatter that myth. I knew the truck would be good, but I didn't realize how good it could be right out of the box – it totally exceeded our expectations, while surprising a lot of WHILE THE EXTERIOR OF THE RIDGELINE MIMICS THE 2017 MODEL, THE INTERIOR IS ALL BUSINESS FOR SCORE CLASS-2 RACING. 0102 SCORE JOURNAL