IndyCar insight: The Indianapolis Motor Speedway road course with Graham Rahal

IndyCar insight: The Indianapolis Motor Speedway road course with Graham Rahal

IndyCar

IndyCar insight: The Indianapolis Motor Speedway road course with Graham Rahal

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Rahal Letterman Lanigan Racing’s Graham Rahal raced Indy Lights and tested an IndyCar on the old-spec IMS road course. Then he helped redesign some of the corners and has now tested on it once more. RACER editor David Malsher asked him what we should expect from the inaugural Grand Prix of Indianapolis. (RIGHT: Paul Webb/LAT photo)

 

RACER: What were you looking to do to improve the circuit?
Graham Rahal: Well first of all, as the MotoGP guys pointed out, the surface was really slippery, far more slick than even a street course, which surprised me. But when they asked me what I thought needed doing, I just felt there was an opportunity to make Hulman Boulevard – the back straightaway – significantly longer, and there was an opportunity to increase braking zones for more passing which means tightening up the corners. The corner at the end of the back straight was just a progressive left-hand turn that just required you to stab the brake and roll in.

The goal should have been, in my opinion, to make it IndyCar’s fastest road course, in keeping with what Indianapolis Motor Speedway is, but it won’t be that way because we’re not using Indy (oval) Turn 1. I wanted to use it, backward like F1 used to. I was doing 192mph down the back straight, the fastest these cars go on a road course so with a tow and with push to pass, I think you could have gone into it 10 lengths back and made a pass into (road course) Turn 1. It would have been awesome.

But it’s still good, right?
Yeah, absolutely. I think the corners are sharper, creating bigger brake zones. The idea was to make the circuit an American-style temple of speed, rather than the more European-style course that you find at Road America, Mid-Ohio, etc. I love those, don’t get me wrong, but with passing and “The Show” being the premier consideration, I didn’t think that would work well for the fans. By doing what they did, building up the dirt mounds, it allowed them to get the fans even closer, so that’s the idea here. We don’t want you in the grandstands because that will feel detached; we want you on the hillsides at the best passing places, up close to the excitement.

Having said that, though, one of the most impressive places you’ll see an IndyCar all year will be into Turn 1 (BELOW). For whatever reason, however they ground the surface on the oval, there’s a phenomenal amount of grip there. You could brake so late it was ridiculous.

Sounds like people will be in a bit of a dilemma regarding wing settings: minimal for those two long straights or more wing for the twisty sections.
Yeah, that’s going to be interesting. One of the reasons that the Sao Paulo track was so good was that you always had to trade off – the straights were so long, you had to trim out, remove downforce. I remember last year, we were puzzled: I was fastest in the practice session, fastest in the warm-up but we were asking “What the hell happened in qualifying?” when I ended up mid-grid even though I put a good lap together. Well it turns out that I was gaining a second through the infield because we had so much downforce, but I was losing a 1.5sec down the three straightaways.

So I think you’re going to find something similar on the GP Indy course: you can’t afford to put too much wing on the car because it’s going to be too draggy in a straight line. But I think we could have emphasized this even more if Turn 1 from the oval had been our final turn onto the front straight. Having said that, the turn from the oval Turn 2 into the infield isn’t as Mickey Mouse as the MotoGP guys had it, but it’s not as good as it could have been.

Still, overall I think they’ve done a good job, because you’re still hauling ass down the front straight, and like I said, you’re braking so late for the first turn. It’s cool, and on the red tires it should be amazing.


 

How hard is it when you go to a new circuit like that? On the positive side, there is some runoff – it’s not like learning a new street course, where you’re confronted by concrete walls as you learn. But that track is very flat, so I’m assuming it’s hard to pick out reference points for braking and turn-in, etc.
It’s very flat, you’re right, and the way it was designed before, you were looking for turn-in points and because you’re so low down, all you see is grass! It was tricky and the first few laps are a bit of an exploration, but once you reach IndyCar level, the drivers are pretty good at learning which way the course goes, and after a handful of laps you’ve got the basics down. Then it’s searching for the best lines.

At Barber, me and Oriol [Servia] were watching the footage and we were both saying, “Heck, I don’t even know where to go in this corner, because everyone’s taking their own line.” Indy will be different, a little more simple than Barber because the corners are a bit more 90-degree, simpler to understand. We did that on purpose. With a wide track like Indy, there’s going to be a hell of a lot of passing when the tires fall off, whereas on your traditional road courses, like Barber or Mid-Ohio or Sonoma, you can be a second a lap slower than the guy behind you and still hold him off with careful car placement.  

Will there be more push to pass available to you?
Well that’s up to the series, but there should be because if there’s a time to put on a great show, it’s when we’re on ABC, and it’s when we’re trying to build up enthusiasm among local fans for a race where we’re lapping 80 or 90mph slower than we will be for the “500.”

So what’s the final turn onto the front straight like now?
Well I’m not sure of the speeds, but it’s going to be a progressive right-hand corner, so it should allow you to follow the car in front quite closely so you’ve got a run into the first turn. The straight will be the length of Indy pit lane plus another couple hundred yards, I suppose, so it’s not massive but the main thing is it’s going to be wide so there’s plenty of opportunity there. I mean, the starts and restarts are going to be ridiculous because it’s so wide.

And can you go around the outside into Turn 1?
Yeah, without a doubt, because there’s so much grip there. And that puts you on the inside for the left-hander that follows. Seriously, until the open test, no one had any idea about it. All I can say is that it should be a very good track for what we do, which is put on some of the best racing in the world. I really believe that.

Is it going to show up which is the best engine, Honda or Chevrolet?
Yeah, that will definitely play a role and thankfully for us, Honda has been very stout. We’ve all been pretty impressed; from the Barber test, to St. Pete, Long Beach and then Barber again, they seemed to me to be doing a fantastic job.

Given the long straights and then the major brake zones, I assume you’re going to be experimenting with gearing quite a bit.
Yeah, when we first ran there, we had gears long enough but I’m not sure we had the right ones for getting out of the tighter corners. Thankfully in IndyCar, that’s all open so we can experiment a bit. But then remember how exposed Indianapolis Motor Speedway is. All those things that apply to the oval regarding wind direction have a pretty significant impact on the road course, too. As you’re coming back to the oval Turn 1, the tailwinds – or otherwise  – will help or hurt you, depending on wind direction and what you’ve decided to run in the gearbox. The same kinda experimentation you do in Indy 500 practice will be applied there, and there’s still going to be an element of luck if the wind changes direction at the wrong time during qualifying or during the race. Not sure that’s true of any other road course we go to. Typical Indy – throws us a curve ball!

(Follow RACER’s coverage of the GP of Indianapolis and the Indy 500 all month on Twitter @RACERmag and @MarshallPruett, and on Facebook.)

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