Erebus Motorsport's Australian-developed version of the M159 V8 Supercars engine will debut in both team Mercedes-Benz E63 AMGs at the September 12-14 Wilson Security Sandown 500 if Tuesday's test at Queensland Raceway is successful.
The 5.0-litre double overhead cam V8 will be fitted to Lee Holdsworth's E63 AMG, as it was the first time the engine ran in a test session in July.
That version wasn't judged ready to race and went back to Erebus Motorsport's Yatala engine shop for more revisions and refinement. Those changes have now been made and the team is confident of a green light for the opening event of the Pirtek Enduro Cup.
The new engine would be a vital performance boost for the team, which broke through for its first V8 Supercars win at Winton in April through Holdsworth and more recently has clamed a series of top 10 results via his team-mate Will Davison.
Holdsworth will partner with Craig Baird and Will Davison with brother Alex in the three-event Pirtek Enduro Cup, which also includes the October 9-12 Supercheap Auto Bathurst 1000 and October 24-26 Castrol EDGE Gold Coast 600.
"The intention is to have the engine in both cars for Sandown," confirmed Erebus Motorsport CEO Ryan Maddison.
"But we still need to go through validating it. It's just a battle against the clock to make sure we have got exactly what we need."
The team took over its engine maintenance and development from German supplier HWA for 2014 and has been working steadily toward its own version of the M159 since then.
These days Erebus General Manager V8 Ross Stone bases himself out of the engine shop, emphasising just how important the program is, although Craig Kirkwood is in charge of development.
Erebus commenced dyno tests of the development engine before the Darwin Championship races, while the first internal local part flowed into the cars at the Townsville event, where a lighter flywheel debuted.
The developments are searching for better response and power across the rev range, while fuel economy progress is also understood to have been made.
"We are very happy with the overall performance characteristic of the (M159) engine, the peak performance is definitely there," Maddison said.
"Other teams have been able to perform better than us not because they have a higher performance engine, but because they have better driveability off the corners.
"So that's the main focus for us, being able to work with what we have to achieve driveability. That's an easy way of saying it, but that encapsulates a lot of work."
Erebus is conscious the engine needs to be right before going in the cars because it will render much of the data collated since the team's 2013 debut out of date.
"The moment we change it (the engine) we effectively have fresh information we are trying to gather to make the chassis and engine work together again," explained Maddison.
"All in all that's what we are hunting at the moment. It is a pretty comprehensive package to achieve drivability that works for us, everything from air coming in right through to air going out. Tip to tip basically."
Maddison was coy on just how competitive the fuel economy of the local engine would be. It's a crucial factor given there has been a deficit to the pushrod Ford and Chevrolet engines in the Falcon and Holden Commodore.
"Until we have the final spec I would be guessing," he said. "We have relative fuel economy now far better than where we were at 12 months ago. We made another leap over summer, but I can't tell you 'yes I have seen the numbers and I am comfortable with them'.
"But obviously that has been part of the chase as well."
Holdsworth has been given the continued responsibility to test the engine because he has been part of the Erebus development program since the team joined the V8 Supercars Championship in 2013.
Erebus will not have spare locally-developed engines for Sandown, but will add an inventory as the season goes on.