Let's dig into the details of the lost wheel on the No. 23 and why the jackman wasn't wrong to drop the car when he did. The stop on the right side goes reasonably well but where things go wrong is when the left front wheel is pulled and the key to the chaos happens as the wheel nut separates from the the socket on the pull.

One storyline that didn't get much attention at Indy is the fact that @keselowski and the No. 6 group were really close to an upset based on the overcut strategy that they were on towards the end of the race.

It all started with this strategy discussion at the end of Stage 2. They pitted with 57 laps to go and decided to hold for fuel to fill up the car as much as possible to let them get close to the end of the race.

The fueler was likely plugged in for around 14 or 15 seconds which should have allowed them to get the fuel cell pretty packed.

The fuel battle between @BubbaWallace and @WilliamByron was incredibly close and some started fairly early in the race.

@charlesdenike and @JRHouston20 decided to hedge as early as lap 53 and held the car an additional second for fuel on that stop while the 24 went on tires. Byron has an elite pit crew and that means that going on tires meant that their stop was completed in just 8.4 seconds and with how these dump cans flow that could be as much as two less gallons of fuel in exchange for track position.

The battery issues in the No. 2 and the No. 21 and the disqualification of the No. 43 at Martinsville are likely all related.

Let's talk about weight at Martinsville and what happened to those cars. Let's start with the basics of what makes a car race well at Martinsville and discuss some concepts of the physics of a race car.

The first thing we need to consider is lateral stability which in its simplest explanation is a gauge of how well a car stays in a straight line.

The No. 19 of Chase Briscoe was hit with a large penalty for modification of a single source supplied
part under the following sections of the rulebook:

-Sections 14.1.C&D&S: Overall Assembled Vehicle
Rules
-Section 14.5.8.A: Spoiler

Let's dig into the details of the parts. Cup series cars are required to run a 7″ x 60″ spoiler face (F) on a tall spoiler base (E) for superspeedway races which is shown on the bottom half of this illustration.

We saw that pit crew members from @JoeGibbsRacing had tablets that would light up in green as a car reached its fuel fill target to tell the driver and fueler that the car can take off.

Let's dig into how this works and how they choose the time when it should change colors. In this video we see a fuel only pit stop on the No. 11 of Denny Hamlin in the Duels last night.

Due to the distance of the race being so short, the car does not need a full fill of fuel so teams try to predict exactly how much fuel to add in order to maximize track position.

NASCAR has added torque sensor details to the rule book.

Ramping up testing with torque sensors is a significant step towards possibly allowing new engine types which could potentially lead to a new OEM.

Let's get into the details of how it all works and what it means. A very simplified way to explain a torque sensor is that it is like a mobile dyno because the sensor is mounted on the driveshafts/axles leading to the wheels which allows it to calculate a torque output figure at the wheels.

The car that Kendrick Lamar used on stage last night at the Super Bowl half time show is a real Buick Grand National.

Let's dig into some of the details and see where it came from and how it was modified. My search for the car started with this great story from @WaterSlicer that gave me a hint of the car being for sale in Riverside, CA at some point.

wired.com/story/true-sto…

Kendrick Lamar owns an authentic 1987 Buick GNX.

GNX stands for Grand National Experimental and only 547 were built. Kendrick owns number 191.

He is deeply ingrained in Grand National lore and has even mentioned internal GM build codes for the GNX in the past. From a post announcing the purchase of his GNX:

"make you realize the only thing that matters in life is that original paper work. that TL2 code"

T2L was an internal GM RPO code that marked a Grand National destined to be turned into a GNX.

Listening to Actions Detrimental and feel like @dennyhamlin might need a whiteboard for a technical explainers to @jareddallen and @TravisRockhold.

Here is a good illustration to add to his explanation on why Xfinity cars can get close and pass but Cup cars can't. If you look at the car when they're far apart, you can see how the air comes off the spoiler of the leading car and and also how the following car can get air under the splitter. The cars will be somewhat comparable in how they perform in these situations.

I do not see a way that having the lifter system installed could have any impact on the right rear droop so I don't believe that it played any role in the LaJoie flip.

Calling it an air jack is incorrect as this is a lifter system that can temporarily increase damper length.

https://twitter.com/AlanCavanna/status/1826297700926574970

I know that the air jack terminology was used on the segment segment in the show but it is incorrect and will cause confusion if people keep repeating it. It's best to refer to it as a damper lift system or shock lift system..

https://x.com/SiriusXMNASCAR/status/1826332484960727443

There have been a lot of opinions on the moves by Austin Dillon on the last lap but best way to analyze them is to look at the actual data so let's dig into his last two laps in a quick thread.

Orange = Lap 407
Blue = Lap 408 In order to get an understanding of what we're looking at we'll start with Dillon's moment of impact with Logano.

If you look on the chart on the right you'll see that Dillon was moving at 105.2 mph and had 30.9 degrees of steering to the left at the moment marked.

The right front wheel on the No. 17 was not fully tight which resulted in the wheel riding at an angle on the hub and eventually snapping. Let’s dig into how that happens.

https://twitter.com/ekanerva/status/1764399108234584301

During a tire change, the wheel has holes on the back of it that need to seat on drive pins that are on the center of the hub around the snout.

Ever wonder what all those buttons and knobs on a race car's steering wheel do?

The steering wheels in our Lexus RC F GT3s have a over a dozen functions and are the command center for our drivers. Let's dig into some of them and how they're used during a race. The top of the steering wheel features three knobs:

TCS: Sets the level of traction control intervention.

GEAR: Sets the mapping for the gearbox and adjusts throttle blip.

ENG: Sets how the car responds to throttle input dependent on a driver’s preference and conditions

Checking out some pit lane stats for Trucks at Kansas and just like in Cup, having that first pit stall is an advantage for driver time on pit lane.

Having an open in or out also appears to be an advantage.

Here are top 15 drivers based on average pit lane time: An experienced driver in the first pit stall can be a huge advantage. The gap from 1st to 2nd is 0.74 seconds but the gap from 2nd to 3rd is only 0.01 seconds.

5th place is over a second behind best.
15th place is over two seconds behind best.

Looking at average driver time on pit lane during the Darlington race last year and out of the 10 fastest drivers only one didn't have an opening either going in or coming out of their pit stall.

The first stall has a huge advantage but openings are helpful even down the line. Those top 10 fastest drivers on pit lane from last years Darlington spring race marked on the pit stall chart.

Here is a comparison of a legal splitter stay versus the illegal one that resulted in a penalty for the No. 3 car based on the photos released by NASCAR.

You can see the two nuts that are bonded to the turnbuckle which resulted in the penalty.

https://twitter.com/NASCAR/status/1654888431397339142

There appears to be epoxy applied at these two joints in order to bond the nuts to the turnbuckle. This would allow the nuts and turnbuckle to move as one assembly instead of having the nuts jam against the turnbuckle to hold it in place.

Hamlin versus Larson lap time differentials during the race so far.

You can see that that Hamlin's car rolled off the truck with a better setup but Larson's car got a lot closer after the first set of adjustments. Hamlin versus Larson lap times from Lap 11 to Lap 38.

Hamlin pit stops so far.

Blue = Driver time to pit box
Red = Pit stop time in box
Orange = Driver time out of box The numbers.

If you've ever taken a peek at engine bay of a Lexus RC F GT3 and wondered what's inside the large carbon fiber box on top, you'll be pleased to learn that it houses individual throttle bodies that are mounted to the cylinder heads of the 2UR-GSE V8 race engine. The carbon fiber trumpets that lead to those ITBs can be seen clearly in this side view photo from TGR.

We can absolutely dig into the fire of the No. 4 at Darlington and explain some of the possibilities and contributing factors. Thread incoming.

https://twitter.com/MilestonesMotor/status/1566999602519330817

To understand what contributes to these fires we have to go back to one of the driver cooling fixes that were done to lower the temperature of the footwell/pedal box which is directly beside the rocker box and where the exhaust comes off the car.