Ford believes its cars go into the NASCAR Sprint Cup season-opening Daytona 500 with a crucial advantage as the FR9 engine's cooling system appears to be coping better with this year's rules package than rival motors.
Technical rule changes, designed to limit the tandem-racing that prevailed at restrictor-plate tracks last year, have made engine cooling more critical than ever in NASCAR's biggest race.
With a smaller and higher opening for the radiator, a lower pressure on its relief valve and a lower rear bumper, cars are unable to push each other for as long as before, some even struggling to do so for a full lap before overheating.
In the closing stages of Thursday's second qualifying race, five-time Cup champion Jimmie Johnson pushed eventual winner Matt Kenseth until overflow started to erupt from underneath the hood of his Hendrick Chevrolet.
"We were right there on edge," said Johnson. "Even without pushing, we're right there on edge. And that's fine design by NASCAR. They don't want us to be able to connect and stay connected for long. But it keeps me worried all day long to see my gauges flash at me."
Although race day ambient temperatures are expected to drop between six and eight degrees celsius relative to Thursday's Duel races, Ford engine builder Doug Yates is confident of having a cooling advantage. A Yates Ford powered Trevor Bayne to victory in last year's Daytona 500.
"It seems like we are definitely doing a better job than our competitors in the cooling area," said Yates. "We saw last year with this engine that it does a really nice job.
"In a perfect world I think we would prefer the weather to be hot like it was earlier in the week. Who knows what we will get [on Sunday] with the rain coming in and everything. Either way, there is kind of a delta there and an offset between us and our competitors right now that we seem to enjoy and hopefully can keep pressing forward on and keep that for a while."
Ford-powered cars have been strong throughout the Daytona week, with Roush Fenway duo Carl Edwards and Greg Biffle claiming a front-row sweep in qualifying, then their team-mate Matt Kenseth winning Thursday's second Duel.
Three-time Daytona 500 winner Jeff Gordon, who drives a Hendrick Chevrolet, reckons being able to run at the front of the pack will be key to keeping temperatures under control. He said cooling may dictate how aggressively he races.
"Everybody is dealing with it," said Gordon. "What it does is it makes it that much more important to be in those first four or five positions. And even then, we looked at the data from the #48 car [Johnson] and their stuff was pretty hot, too, before he started pushing.
"So, it's just going to weigh more into our strategy for the race and how aggressive we're going to need to be when they drop the green.
"We're starting 16th so we know we're in a vulnerable position right from the start of the race of either being in the conserve mode or go into a high-risk type of situation where you've got to be super-aggressive."
Weather forecasts show a 50 per cent chance of rain for the start of the race and a steady 40 per cent for the reminder of the afternoon. Kenseth won the last rain-shorted Daytona 500 in 2009.