The famously bumpy Sebring short course is the closest that teams can come to simulating a streetcourse surface, since the others are necessarily temporary tracks, and today’s test there was the fourth and final sign-off test run by IndyCar for the new universal-aerokit-equipped IR12.

Honda’s official 2018 car tester Oriol Servia shared seat time with James Hinchcliffe in the Schmidt Peterson-run machine, while Scott Dixon drove a Chip Ganassi Racing car. In the Chevrolet camp, the Bowtie’s 2018 tester Juan Pablo Montoya shared his Penske car with newly crowned champion Josef Newgarden, while Spencer Pigot used an Ed Carpenter Racing machine.

Servia, who was already enthusiastic about the new car following superspeedway, short-oval and roadcourse testing said that drivers and teams would find the 2018 car hugely demanding on street courses, and thereby achieve one of IndyCar’s prime objectives.

He told Motorsport.com: “Well first of all, the test went well and we did everything we were supposed to. Actually I think it went even better than IndyCar hoped because we wanted it really hot to make sure that the cooling for the engine, electronics and brakes was good enough. And s***, it was hot! It was 97degF even as I left the track at 5.30pm so in the middle of the day it was over 100. And everything worked fine.

“But the car – yeah, it was a real handful, and that’s good! It’s the most difficult we’ve found anywhere in these four tests, and man, it was so loose. So loose. And that’s what the good drivers wanted, right?

“It’s going to make the teams have to find totally new setups. The streetcourse setups for the last three years will not work at all with this car, so everyone’s going to have to go back to the drawing board to make this car work.”

Servia confirmed that the straightline speed improvement over the current car was noticeable both in the cockpit and from a fan’s viewpoint.

“After I handed over to Hinch, I walked around the track as a spectator, and let me tell you, the cars are visibly faster on the straights – which is very good. Like I told you last week, the last three years with all this drag from the manufacturer aerokits, the cars looked slow on the straights.

“This car – it’s how it should be. At the wheel, you feel it sliding around under braking, and it’s so loose on power-down out of the corners. The drivers are going to have to work again, and learn how to be progressive on the throttle.”

Pigot, who becomes Ed Carpenter Racing’s fulltimer in the #21 car next year, after one-and-a-half seasons as the team owner’s road/street course driver, echoed Servia’s enthusiasm.

“Everything that Montoya and Servia have been saying about the car is true,” he told Motorsport.com. “It’s very different from the 2017 car – less grip, you’re working the steering wheel more, sliding around a lot more, the brake zones are a bit longer, the power-down is less straightforward.

“You’re definitely having to modulate the throttle to prevent wheelspin, and I don’t just mean in the tight corners, either. As you accelerate through second and third, the rear of the car is getting lively.”

The 2015 Indy Lights champion said the challenge of the new car was no greater than that of the 2015-’17 cars, but its demands were very different.

“I don’t want to disrespect how it was to drive the previous car – that was challenging too,” he remarked. “But this is challenging in a different way, and it’ll take a different approach to things. The G-forces are a bit different but I didn’t notice it in my neck specifically; I noticed it more through the wheel; you can feel there’s less steering load.

“It’s funny though, because although the car’s less planted, it’s not less physical to drive, because you’re having to work the wheel more, turning left and right multiple times throughout the corner.”

Pigot agreed with Servia’s synopsis that the straightline difference between last season’s car and this one was very noticeable.

“Yeah, you definitely feel there’s much less drag,” he said. “It’s pulling harder and keeps pulling, and at the end of the straight you definitely feel it’s moving pretty quick.”

The 23-year-old said that although the car was a bit of a culture shock from what he’d gotten used to over the past two seasons, he felt that teams will make the cars a little more docile over the course of a season.

“The team was obviously getting used to the car, and over the course of the day they made it a little bit easier to handle,” he said. “At the start of the day the rear was sliding on entry as well as exit, so we made some gains. And there’s more to go: it’s great to have the Manufacturer Test Days before the end of the year for us to learn it a bit better.

“But you’re not going to change the car’s basic behavior – it’s going to wake people up a bit! Especially on a track that’s ‘green’ before we’ve laid rubber down, I think it’s going to be a pretty big handful. But that’s great; it’s exciting.”

Video footage from the Sebring test was uploaded to YouTube by "Lanky Turtle":