The three-Test series, which, it was announced on Tuesday, will be played in Cape Town due to Covid-19 issues, has been long-awaited.
The Springboks have only been able to play one Test, earlier this month against Georgia, since their Rugby World Cup triumph in Japan in 2019.
The Lions have pushed ahead with the tour when many felt the better option was to delay it for a year in the hope Covid-19 issues might have eased.
But both sides have moved the naming of their sides forward by 24 hours.
Furlong said while their games against the South African franchises had been easy wins, the Stormers reminded them at the weekend of what to expect, especially in the forward contests.
"That kind of scrum and maul dominance is so ingrained in the Springbok DNA. It's a huge challenge for whatever forward pack and substitutions are selected," he said.
"It's [also] one of the great things about playing Test series' in South Africa. I think the lads will be up for it.
"Who wouldn't be up for it? You know you're up against a passionate [nation] that takes pride in their work and art at scrum time.
"Yes, we've played the franchise teams mostly, but they still take massive pride in their scrum, and they are still big men. It's been tough, and it's been a good workout for us.
"We've been trying to get on the same page very quickly, to get the feel of the scrum," he said.
Furlong did not expect the lack of Test rugby in the last two years to be an issue for the home team.
"I know they had a few issues with Covid and self-isolation there, but look at the squad they have.
"They have the bones of a World Cup-winning front row, and we all know what they did there. They have players that didn't play against us in the SA A game who will come back in.
"They are very dangerous operators," he said.
"It's going to be big boy rugby at a big stage, and you can feel that around the place. You can feel that it's a big week and it has a lot of importance on it," he said.