Our drivers on the challenges of COTA, importance of teamwork and unchanged mindsets...
Lewis enters this weekend's race in Austin, Texas, with a 67-point lead in the Drivers' Championship. But, his mindset remains unchanged and he's taking it one step at a time.
"As a team, none of us are saying how cool it would be if it happened this weekend or the next, we're not focussing on ifs," he said.
"We're focussing on making sure that we deliver. There's still 100 points available. We can just never be complacent in life, and in a Championship as intense as this.
"We expect Ferrari to punch back hard here this weekend, so we can't be relaxed in any way, shape or form.
"We've got to make sure we come here and raise the bar again. So, I'm definitely not thinking this weekend, how's it going to feel if we do the job.
"Because I've got to do the job and that just adds more pressure and you don't need more pressure.
"So, focussing on making sure that I drive the best that I've driven all year long and we get the car where we need to get it. Nothing is a given."
Valtteri believes the team has found extra motivation this year thanks to the more intense competition with Ferrari and Red Bull, which has helped push us even further.
"I think especially when things get tougher and when the competition gets tougher, like this year... half of the year we didn't have the quickest car, we were not the best team," Valtteri admitted.
"But we have been able to improve the car step by step, all the time. Learning from every mistake we have done, learning from every weakness of the car to make it better in all areas.
"It's not a massive jump in terms of performance or team work, it's just fine details, getting those right race by race.
"The only way to make that happen is teamwork. The team has stayed united. At no point has there been panic.
"I think the extra motivation came from the competition. For sure, the team needs leaders to make that happen, but we have been able to work together as a team with good spirit and the key for us has been to really make sure we set the goals for ourselves that we want to target.
"For the other teams, it is easier for them as the goal is to beat us, and that's their motivation. But, we need to raise our bar even higher.
"That is teamwork. Every human needs to be able to work together. At the factory, in the race team, me and Lewis. We need to be able to work together for the same goal and put the energy in the same direction."
While Lewis isn't focusing on potential Championship glory, if he does win the title, it'll be his fifth Drivers' crown in F1.
That'll move him equal with the great Juan Manuel Fangio, who claimed two of his five Championships with the Silver Arrows (in 1954 and 1955). What would that mean to Lewis?
"Imaging myself driving some of those cars back then? I have driven some of those cars," Lewis replied.
"I've had a go in Stirling Moss's car, some of the Silver Arrows they had, around the old Monza circuit, for example, with Sir Stirling, which is pretty intense.
"Fangio is always... he's like the godfather of the drivers' sport for us. He's the godfather for us.
"One of the greats from the beginning and will always be admired in the sport.
"It is crazy to think that I'm embarking on a similar number of championships that he had."
Valtteri's determined to end this season on a high, after a tough first half of the year, which has left him out of contention for the Drivers' Championship.
He believes he is performing better this year than he did last year, and already has his sights set on his 2019 targets.
"My goal is to be stronger and one day things will come together. Definitely the first half of the year is extremely important to collect as many points as possible.
If the gap is not big, we are going to be fighting for sure, hopefully until the end. This year, the way things went, the points gap became too big.
"And here we are, but I do understand the name of the game in this sport. I think performance-wise, every race this season I have been able to perform better than last year.
"That's what I'm trying to continue to keep doing. I am learning all the time, and I am very keen to be better next year and hopefully bring good results."
Lewis loves spending time in the USA and also has a strong track record at the Circuit of the Americas, with five wins from the six races it has hosted.
He enjoys the challenge that COTA presents drivers with, but also likes the spectacle of the event itself and the enthusiastic fans who attend.
"They don't make tracks really like they did in the olden days," Lewis explained. "The older circuits that you'd go to, you'd dream of going to, watching the legends drive there.
"So, some of the new tracks aren't really that good but this is one of those that is. It's got great character and from day one when we arrived here, there was a massive crowd that came who I'm sure, at least half of them, probably were new to the sport which was great.
"So, it had the impact it was meant to have, and I think every year it's kind of been growing. Just driving the track is a massive challenge and also you can actually race here.
"You can follow which is one of the downfalls of some of the circuits. I think that's really why I've enjoyed it a lot because I've had the chance to have races here, real races.
"And obviously there is that great sporting heritage here and people are genuinely super enthusiastic about sports, no matter which sport it is.
"And the last race here that we had, the whole spectacle, I think, was probably the best of the whole year, the whole build-up and everything I thought was great. It's great to celebrate the culture wherever you go."