The team is currently holding sixth in the constructors' table, but Aston Martin closed the gap to 15 with a good double finish in Singapore last weekend, and Haas and AlphaTauri are both just 18 points behind.
The Swiss outfit opted not to fast track the new wing for Singapore because of the obvious risk of damage, and it has just two examples in Japan for Valtteri Bottas and Zhou Guanyu.
Given Friday's sessions being lashed by rain, the team opted not to risk an accident and started the day with the old wing.
However Bottas was given the new one for his final two runs on a drying track in FP2, allowing the team to gather some preliminary data.
Both drivers will run it from the start of what is expected to be a dry FP3 on Saturday. The revised design features new wing elements as well as a different attachment to the nose structure.
The team will bring its last batch of updates of the 2022 season to the next race in the USA.
On Thursday Bottas indicated that he hoped to see some gains in high-speed corners, and that was validated even in the limited running he did on a damp track after switching to it during the session.
"It definitely gave us a bit of stability in the high-speed," he said when asked about its performance by Autosport.
"That's what I felt, which is what it needed to do. Obviously, we're missing quite a few sensors, because of the wet conditions.
"So we can't, aero number wise, measure that much. But feeling-wise, it was like it should be.
"At least we got the delta in the balance, like how much it changes in the weather, etcetera, so we can estimate a little bit for tomorrow. But it should hopefully be quite straightforward."
Bottas acknowledged that it was good to see new parts still coming through the system.
"It definitely would have been nicer to have it earlier, but better late than never. And I think also we have something coming for Austin. But it's also the case that whatever we find this year, I think it's going to benefit us next year.
“So it's not just this year's car development, it's also the future. So yeah, hopefully it works. Correlation has been good [this year], so there's been no issues."
Alfa Romeo boss Fred Vasseur is confident that the wing will generate some performance, adding: "It's a decent step forward.
"And also we have to consider that we will carry over some parts for next year, so it's an ongoing development even for the next season.
“Suzuka is the right place also to introduce it. I think it made sense to do Singapore with the old ones, and to turn the page after Singapore.
“We are expecting some smaller updates for the next race, and then I think it will be done for the season.”
