Insight: How a 100-Year-Old Technical Paper Helped Take Acura to Rolex 24 Win

by John Dagys (Sportscar365) HPD President David Salters reveals his company's solution for an oil dilution dilemma in the build up to the GTP class debut...There were a number of unknowns heading into January’s Rolex 24 at Daytona for competitors in the reborn IMSA GTP category. With brand-new prototypes running a new hybrid powertrain on new Michelin tires and with a new renewable fuel from VP Racing Fuels, there was not much that manufacturers and teams could lean on from past WeatherTech SportsCar Championship seasons.

One of the wrenches thrown into the mix was the introduction of an 80 percent blend of renewable fuel, to be used exclusively in the GTP class, that inadvertently led to an oil contamination issue inside the powerplants.

While each LMDh manufacturer dealt with the challenge in different ways, Honda Performance Development, Acura and Honda’s U.S.-based motorsports arm, went back into the automotive archives, with a technical paper that was written 100 years ago, to help solve a 21st century issue.

HPD President David Salters tells the tale: "The fuel supplier did a brilliant job to move heaven and earth and get the fuel here but of course we were all running late (because of supply chain challenges). We started testing the fuel in November and we found some issues with oil dilution.

"This fuel is brand-new, it didn't really exist in the world before. What were we going to do about it?

"We noticed that we were getting quite a lot of fuel in the oil. Normally you might expect 1 or 2 percent and this was ten times more than that.

"But one of the guys who leads our development (Jason), went away to get the books out and understand what causes oil dilution.

"These days it doesn't happen very often but it used to happen a long time ago when fuels and lubricants were very different. The quantities we get now are minuscule. In the early days of new stuff, like a new fuel now, you got quite a lot.

"We actually found a paper that was 100 years old. A group at a university had modeled the equilibrium status of how fuel and oil interact.

“So we did loads of classical sums and we were able to use a 100-year-old paper with 21st century measuring equipment and we were able to figure out how the oil and fuel would reach an equilibrium state.”

"We kept it at a manageable proportion and we understood how much oil we needed to change to keep it the right way and then we've since done other things where we're able to reduce it,” Salters explains.

"At Sebring we had it all under control. We just kept learning and we're still learning. We’re now working with the oil supplier, who now knows a bit more about it on how to deal with it, and we can change some of the running conditions so we don't put as much fuel in the oil.

"We've done the engineering and now it's more-or-less under control now. We don't have to do anything special anymore."

Salters, who was one of the proponents for a switch to a renewable fuel, praised IMSA’s adoption of the new blend, even if it created some initial headaches in the critical weeks leading up to the season opener. READ MORE