Q: I am curious to know why current IndyCar drivers “snake” along the straightaways when running solo. Do current tires have a lot more stagger with the right-rear tire’s diameter? Does the Dallara IR18 create a lot more dirty air (that bounces off the walls) that today’s drivers are trying to avoid than older Indy cars? During Arie Luyendyk’s 1996 record qualifying run, he didn’t come away from the walls nearly as much as today’s drivers do.
Here’s a link to Arie’s record run.
Loren
MP: It’s the suspension setup to help the cars turn left. Rather than hold the wheel firm and fight its natural tendency to turn left down the long straights, drivers let the car turn and in doing so, reduce friction/scrub that would otherwise slow the cars on the straights. They then turn to the right to get setup for the proper line to carve through the corner. If you’ve ever had a shopping cart with a wonky wheel that made it want to pull to one side, it’s a fight it to make it go straight down the aisle. Same exact principle here where, while running solo, it improves speed if you avoid the fight.
Q: Could Stefan Wilson’s height made him more vulnerable to injury than, say, a driver that is 5’9″?
Jim
MP: According to one Indy 500 star who I spoke with, the answer is yes. To fit their helmets below the aeroscreen, the tallest drivers — ones with long torsos — must hunch forward into something that looks like the letter C while making their seats. That curvature creates an issue in some crashes where the built-in bend creates a weak point for the energy to exploit.
Q: Perhaps I’m mistaken, but I believe that in most racing series those behind the scenes are doing everything they can to eliminate weight from the cars to make them lighter, and therefore faster, without compromising rules and safety. Is this true in IndyCar?
All of these cars are identical spec-wise, so I presume that they are all likely to be pretty much the same weight. If that is true, as I watched Graham Rahal lack the speed to make the 500 during qualifying, I was wondering if he was possibly being handicapped by his body weight relative to the other drivers.
For example, Santino Ferrucci at 117 pounds is hauling around approximately 70 lbs less than Rahal, who weighs in at approximately 189 lbs. I know that the RLL team was way off the mark compared to other teams, but could this weight variance have been a factor in Graham not even being able to outqualify his own teammates (who weigh in between 130-154 lbs)? Maybe I missed it, but I heard nothing mentioned nor did I read anything about the extra weight being a factor in the speed.
Duke, Buckeye, AZ
MP: It’s informally referred to as the “Danica rule.” She was indeed the lightest driver in the field during her full-time IndyCar career, and the series back then did nothing to equalize its drivers until enough complained and a ballast system was adopted.
Drivers are required to get to IndyCar’s scales within 15 minutes after the end of the first practice session at each event to get weighed, and with that official number in place, crews then add or remove ballast to make sure a Graham isn’t at a weight and performance disadvantage compared to Jack Harvey by bringing everyone up to the same minimum weight. There’s a limit, of course — the series won’t ask teams to ballast everyone up to make a 250-pound driver equal, because there’s only so much room for ballast at the leading edge of the tub.
Q: Regarding Callum Ilott and the change to the car, you wrote:
“My guess is there was something wonky happening with the floor/underwing while at speed. Callum said they did torsional rigidity tests and found no issues. His main complaint was the erratic handling, which, in the absence of a broken shock, sounds like a non-linear aero issue. Listen to the good crew chiefs, and they’ll tell you that some floors are problematic. That’s my guess here, and as for the chassis, I’m not sure what will happen to it. I feel confident in saying Ilott will pass on using it again…”
That is great insight, and it made me wonder why, in the era of a chassis that is a decade old, it requires desperate moves like it was 1993-95 IMS vibes.
If it’s an aero/undertray issue, why would a team swap out an entire car instead of attempt a simple undertray replacement first? Did JHR try that along the way first? I get variances in manufacturing can create issues for a component but seems a drastic change to dump the entire car in this era.
Full disclosure: I’m also old enough to barely remember a Duracell/Marlboro livery, but that was desperation at its finest and honestly I think we can all agree Harvey’s “buzzer beater” may be the closest to that that we have seen in nearly 30 years.
Am I missing any other attempts that smacked of a Hail Mary between those two?
Ed, Westfield
MP: Not sure why the floor swap wasn’t tried sooner, and by the time the poop hit the fan, making smallish changes seemed like a waste. They did the big change and helped themselves by doing so. There were a few head-scratchers from Ilott’s team during the opening week of practice.
Jack’s got balls, which I’ve never questioned. Happy for him, and happy for Graham with his surprise chance to avoid his dad’s fate in 1993. Kyle Kaiser dropping Fernando Alonso in 2019 is the all-timer of the modern era, I’d say.
Q: During Indy qualifying, the tires seem to fall off quite a bit over four laps, which makes sense as they are being pushed to the limit. In race trim, tires also fall off over the course of a stint — just not as rapidly since the speeds/forces are lower. Curious to know just how much greater the degradation is when at the limit. If a new tire is 100/100, how much is left after a four-lap qualifying run? How much is left after a full green-flag race stint?
Wesley, Summerville, SC
MP: Main difference here is the absence of comfy downforce in qualifying in order to make all that extra speed. There’s barely enough downforce on most cars to get them through the corners and as a result, they’re sliding and scrubbing a lot more than they would in race trim with all that downforce piled on to extend their life by avoiding the scrubbing and grating that takes place in low-downforce trim.