Home » How Teams Try To Win NASCAR’s Strangest Trophy At One Of Its Toughest Track

How Teams Try To Win NASCAR’s Strangest Trophy At One Of Its Toughest Track

Marinsville Nascar
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There are plenty of storied tracks on the NASCAR schedule, but perhaps none more so than Martinsville Speedway. It is the only track that has been on the schedule every year since the inaugural season of the NASCAR Strictly Stock Division, which evolved into the Grand National Series and is now known as the Cup Series.

The first NASCAR race at Martinsville Speedway was won on September 25, 1949 by Red Byron who finished 3 laps ahead of Lee Petty to bring home a $1,500 ($19,935 in 2024) payday. Since then, the speedway has been visited 237 times by NASCAR’s national touring divisions; 150 Cup, 41 Xfinity and 46 Truck. 

Vidframe Min Top
Vidframe Min Bottom

Rookies are often warned about coming to Martinsville for the first time. It is one of the trickiest ovals on the schedule, and a place where the cream truly does rise to the top. The 10 winningest cup series drivers at Martinsville are as follows; Richard Petty 15, Darrell Waltrip 11, Jeff Gordon 9, Jimmie Johnson 9, Rusty Wallace 7, Dale Earnhardt Sr 6, Fred Lorenzen 6, Cale Yarborough 6, Denny Hamlin 5 and Geoff Bodine 4. Hendrick Motorsports, the winningest organization in Cup Series history, owns the record at Martinsville with 28 wins. Since returning to the Xfinity Series schedule in 2020, the six races have been evenly divided between powerhouse teams Joe Gibbs Racing and JR Motorsports with three wins apiece. 

Martinsville Clock

Since 1964, victory at this historic track comes with one of the most coveted trophies in NASCAR, a grandfather clock. H. Clay Earles, the original owner of the circuit, wanted a trophy that would stand out and wouldn’t just sit on a shelf collecting dust. He figured that a grandfather clock would be something that the driver’s family would enjoy as well. To this day, the winning driver from each Martinsville race takes home a Ridgeway Fremont Grandfather clock. Much to the chagrin of my roommates, I am fortunate enough to have one of these clocks in my living room thanks to our 2021 win with Noah Gragson. It is easily my most prized possession.

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What Makes Martinsville Speedway So Unique

Often referred to as “The Paperclip”, Martinsville Speedway can best be described as two drag strips with a U-turn at both ends. The 0.526 mile (0.84 km) short track consists of two 800 ft (244 m) straightaways connected by the sharpest, and second flattest, corners of any oval on the NASCAR calendar. 

Martinsville Speedway features 12 degrees of banking in both of its 202’ (57m) radius corners. For comparison, Bristol Motor Speedway is also 0.5 miles in length but the corners there have a radius of 242’ (m) and feature progressive banking going from 24 degrees at the apron up to 28 degrees at the wall. The 1-mile paper clip layout of New Hampshire Motor Speedway features corners with 5 degrees of banking but with a radius of 450’ (m). The long and short of it is that Martinsville Speedway presents a unique set of challenges for teams and drivers that aren’t seen anywhere else on the schedule.

Martinsville Speedway represents everything that makes NASCAR short-track racing great. At a track this small it is impossible for the drivers to get away from one another, leading to a lot of full-contact racing. If the entire field was lined up bumper to bumper, it would cover 24% of the length of the entire track. 

The flat, sharp corners make this a predominantly one-groove racetrack with drivers wrapping their line tightly to the curbs on the inside of each corner. Unlike road course curbing, however, these curbs are tall (almost 10” or 25cm) and steep. Any contact with these curbs will push the driver up and out of the groove and likely damage the nose of the vehicle.  

How To Race It

Nascar Xfinity Series 2023: Nascar Xfinity Series Call811 250 April 15
#48: Parker Kligerman, Big Machine Racing, Big Machine Racing Spiked Chevrolet Camaro/Barr VIsuals

There are three traditional lines that you will see drivers take around the paperclip. The first is simply wrapping the curb all the way around the corner. If a driver’s vehicle is perfectly balanced and they are somewhat by themselves on track this is the approach you will see them try to take. A nice simple, rounded corner with a centered-up apex and the left front tire planted right next to the curb.

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Second, and most common, you will see drivers take a “diamond” line, or in road racing terms a double apex. If the car has a lot of turning ability it will often be perceived by the driver as being very loose on entry and exit of the corner. Taking this line allows drivers to manage an oversteering vehicle as it straightens out their entry and exit phase of the corner while the car has enough rotation to quickly pivot in the middle. A tertiary benefit of this approach is that it protects the driver from being overtaken. Entering shallow makes it difficult for the trailing car to out-brake them and get to their inside. Exiting low and straight gives them a better launch to help them pull away from said trailing car. You can see a rough example of this line in a screenshot from the Driver61 YouTube channel where he is describing a right-handed corner.

Double Apex
Screenshot: Driver61

The third, and least common line is the late apex. This line asks the least of the vehicle in terms of cornering as it takes the widest arc and still provides for a straight launch out of the turn. The downside is that it leaves a driver overly exposed to trailing cars getting to their inside on corner entry and is thus rarely seen when racing in traffic, which at a short track is almost always.

Because of the single-lane nature of this speedway, track position is at a premium and passing tends to get a bit physical. Drivers tend to treat passing here the same way F1 drivers approach Turn 1 of a Grand Prix where the first one to the apex is the victor. You will see a lot of late lunges as the overtaking driver attempts to brake as late and shallow as possible in an effort to get any amount of overlap on the car ahead of them before they reach the corner. If said overtaking driver gets a bit greedy on entry and misses the corner, they will most likely make contact with the defending driver’s left rear and potentially send them spinning. See below as Ryan Truex (red and white #19) unsuccessfully attempts to make this move on Sam Mayer (black and white #1) during the 2023 Xfinity Series spring race.

GIPHY via NASCAR

If the defending driver manages to get into the corner ahead the overtaking driver you will likely see what we call in short-track racing “rooting and gouging,” or more bluntly just purely forcing your way next to them. Applied properly, the overtaking driver can use their bumper to upset the defending car mid-corner and force them up slightly out of the racing groove. This slight upset will unsettle the defending car as its driver attempts to apply throttle leaving the corner and provides an opportunity for the overtaking driver to slip to their inside. Once position has been established on the inside of the defending driver, the overtaking driver will try to run the diamond line to try and force the defending driver up and out of the groove in order to complete the pass. You can see below as Brandon Jones (yellow #19) applies this move to take the lead from Ty Gibbs (black #54) on a late race restart during the 2022 Xfinity Series fall race.

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It is often said in short-track racing that if the right side of your car is beat up you’re moving forward and if the left side is beat up you were in the way.

Such physical racing leads to a high frequency of cautions, followed by aggressive restarts. Drivers in the outside lane of a restart will be doing everything in their power to force their way back into the inside line. Drivers in the inside lane will be doing whatever they can to prevent these drivers from finding a spot in line. If you see a driver get caught up in the outside lane this is referred to as being “hung out to dry” as they will slowly lose ground to drivers on the inside until they can finally find themselves a spot to get in line.

It’s All About The Brakes

A distinct inflection point for Cup Series racing at Martinsville can be seen at the introduction of the Next Gen car. In the 44 Cup Series races from 2000 through 2023 there was an average of 12.8 natural cautions per race. In the 4 Next Gen races there has been an average of just 3.5.

The Next Gen car introduced wider tires, and therefore a larger contact patch, bigger brakes, as well as a 5-speed transmission that allows Cup Series drivers to shift during the lap at most tracks. This combination has been significantly detrimental to the quality of the racing product at these tracks once lauded by fans. Having a larger contact patch gives the drivers more grip which makes it harder to nudge other vehicles out of the way. The added grip also means it is less common to see drivers make mistakes. Better brakes made for a shorter braking zone, which makes it more difficult for drivers to out brake the car in front of them. With the ability to downshift in the corners, it is easier for drivers to recover from a mistake or contact. Adding all three of these together means that overtaking has become borderline impossible without significant contact or a tire advantage.

The unique nature of the speedway means that teams have to get fairly creative in order to make a vehicle handle properly. Braking and acceleration are the name of the game at Martinsville. Twice per lap, drivers will accelerate up to roughly 120mph (193 kmh) before immediately braking down to 55-ish mph (88 kmh). 

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In simple terms, any moving object has what is called kinetic energy. The amount of energy can be calculated by one half of the object’s mass (weight) times the square of its velocity.

Formula

The kinetic energy dissipated by a car’s braking system in one lap at Martinsville Speedway is enough to power the typical American home for roughly 17 minutes. And that’s just in ONE lap. The stop-start nature of a lap around this track means that weight reduction is of utmost importance. Teams will go to extreme length to reduce weight right up to the minimum allowable amount and it is not uncommon to see cars be disqualified in post-race inspection for not meeting minimum weight, as Brad Keselowski was after the 2022 Fall Cup Series race.

During the truck and Xfinity races this weekend, which happen at night, you will notice very early in a run that the vehicle’s brake rotors are glowing bright orange. In a typical 21 second lap, drivers will spend almost 9 seconds with their foot on the brake pedal, and dissipating that much kinetic energy creates a ton of heat. NASCAR Rule 14.15.1.3-A mandates that brake rotors must be made of only magnetic cast iron or cast steel. For cast iron or steel to produce this distinctive orange glow it must be heated to roughly 1,600 F (870 C). 

Glowing Rotors

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While the actual braking loads and total peak heat generated is less than you would find at a road course or at somewhere like Pocono Raceway, the frequency of deceleration is what makes this place so tricky from a mechanical standpoint. With the straightaways only being a mere 800 ft in length, there is only about six seconds between braking events. At most other tracks there is a long straight following each hard braking zone which gives everything time to cool down. At Martinsville, there is no break for the brakes and drivers must be careful not to abuse their vehicle or they will struggle to make it to the end of the race.

With this much heat being generated, teams must take careful consideration when it comes to cooling the tires and brakes. Excess heat will cause the tire pressures to increase above their optimal range and lead to decreased grip at that corner. It can also cause the brake fluid to boil if the brake caliper temperatures are not controlled. Drivers will refer to this as the brake pedal feeling “long”. Once the fluid starts to boil it becomes easier to compress and therefore generates less clamping force at the brake rotor. In extreme cases, brake heat can actually cause the bead of the tire to begin melting and unseat itself from the wheel rim, sending the driver out of control and into the wall.

From the NASCAR rule book, you can see a typical front brake cooling assembly with one hose going to the tire bead, one to the brake caliper and one to the wheel hub. Each hose is allowed to have one fan installed in it to draw in more air flow. Teams are also allowed to apply tape to the openings of these ducts in the nose of the vehicle. More tape (less opening) equals less cooling but more downforce and less drag. The teams must make an informed calculation on how much cooling area they want open. This calculation is influenced by the air temperature as colder incoming air means more heat removed from the braking system. 

Brakes 1 The rear brake cooling assembly features air inlets on the rear side window with ducts directing air flow to the underside of the car. Again, see below from the NASCAR rule book.

Brakes 2

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The rear brake cooling assembly features air inlets on the rear side window with ducts directing airflow to the underside of the car. Again, see below from the NASCAR rule book.

If you’ve ever taken an on-ramp too fast and felt yourself flung to one side of your car you have felt lateral force. This lateral force (or centrifugal force) acts upon a vehicle at its center of gravity (CG). The CG height is essentially the average height of all the weight of the vehicle. A higher CG means more roll and vice versa. When building a Martinsville car, teams will do everything that they can to reduce the weight of components higher in the vehicle so that they can add weight to lower components or place ballast weight as low as they can. In 2021, former Trackhouse crew chief Travis Mack was penalized for a ballast infraction found in pre-race inspection. NASCAR stated that “the No. 99 Chevrolet was found with ballast outside of the approved container.” Allegedly, the team had filled the left side jack post with lead.

Moment Of Interia

The final challenge from a setup standpoint is getting the vehicle to be able to launch off the corner without spinning the wheels. A soft rear suspension allows for maximum weight transfer to the rear wheels on throttle. This will, obviously, take weight off of the front wheels during acceleration, reducing turning ability late in the corner. The same weight transfer applies in reverse under braking with a soft rear suspension transferring more weight onto the front wheels getting into the corner. This will make the vehicle want to oversteer on corner entry. The lighter load on the rear wheels during braking also makes the driver susceptible to experiencing wheel hop. For more on this phenomenon, you can read this except from my piece about Circuit of the Americas.

Stock cars pitch forward heavily under braking meaning that the rear wheels are very lightly loaded. Because the rear wheels are connected to the engine and drive line, they will not lock under braking like the front tires will. Instead of lockup, drivers can experience “wheel hop” which is significantly worse. Under braking the rear tires are subjected to simultaneous opposing forces. The brakes and contact patch are trying to stop the wheels from rotating while the drive line and are trying to keep them rotating. If these forces become imbalanced the drive shaft and axles will begin to twist in a similar manner to a sway bar. When rear traction finally breaks, the drive line will snap back to its natural state and wheel hop begins. In this instant the drive line of the car is acting like an undamped torsion spring causing the rear wheels to literally hop up and down, making the vehicle impossible to control. See below

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The Damn Pit Wall

If a driver manages to survive these numerous challenges presented while racing in Martinsville, it can all come unraveled on pit road. If you are new to this series, here is a refresher on curved pit lanes from my piece about Phoenix Raceway. If you’ve been following along, feel free to skip ahead:

Pit road speed in NASCAR is calculated based on a time over distance formula, not instantaneous speed. The pit lane is divided up by a series of timing lines and a driver’s rolling time is measured via the transponder in each section. At each track there is a declared pit road speed and drivers are given a 5mph buffer above that before receiving a penalty. For example, if the pit road speed limit is 45mph, drivers and teams will try to run 49.9mph down the pit lane. For the sake of simplicity let’s just call it 50mph and assume that the timing lines are 100 feet apart. Under these conditions it would take 1.36 seconds or longer to cross this section legally. Anything under that time would result in a penalty.

There are certain tracks on the schedule like Phoenix, Bristol, and Martinsville where the pit lane has a corner in it and is not straight from pit entry to pit exit. This makes the time over distance calculation a lot more interesting. NASCAR places the timing loops on the pit wall. If pit lane is curved, then cars will travel along a path longer than the one between the timing loops because they are on the outside of the pit lane. This means that even if the car is still travelling at 50 mph, the pit lane timing system would register it at several miles per hour slower. Teams will gather data on how much further this radius is in the path of travel versus the distance between timing loops and bump up the RPMs and speed to match the further distance.

The math is elementary but the execution can be a bit tricky. If the driver accelerates too early before the curved section begins, they will likely receive a penalty. Ditto for not slowing down quickly enough when the pit lane straightens out. The driver must also be careful to keep the vehicle traveling on the path along which this higher RPM was calculated. Teams will give their driver a visual reference for where to place the car to maintain this path. You can see that there are white hash lines towards the outside of the pit lane. If the team calculated the higher RPM for the car to have its left side tires on the hash marks, the driver could easily earn a penalty if they take the corner too sharply and run with the left side tires, for example two feet inside of the hash lines.

A curved pit lane also creates challenges for the pit crew as well. Per the NASCAR rule book, “Crew member’s feet and/or pit equipment must not touch the pit road surface before the vehicle is one pit box away from its assigned pit box or the equivalent marked distance.” When a car is coming around a corner it can be difficult for the pit crew to time their jump off the wall. This penalty can be negated by the crew member getting back onto the pit wall before beginning service on the vehicle. While this will avoid a penalty it will slow the stop down significantly and result in a loss of track position. Chase Elliott’s jack man, TJ Semke, famously avoided this penalty at Martinsville in 2020, ultimately saving their race and their season as Elliott was able to advance to the Final 4 where he won the championship. Clearly, it pays to know the rules.

You can see here how blind the pit crews might be when it comes to spotting their car coming down the pit lane.

Pitlane
Photo: JR Houston/23XI

Unlike most pit lanes on the NASCAR schedule where drivers in the first pit stall can accelerate carefree off of the pit lane, at Martinsville Speedway the actual end of pit road is far enough away that drivers can speed if they aren’t careful. The distance from pit stall 1 to the P12 timing line means that a driver leaving this stall will already have accelerated significantly by the time they reach the final timing segment from P12 to PO. This issue appeared in both Cup Series races last year and saw both Ryan Preece, stall 1 Spring race, and Martin Truex Jr, stall 1 Fall race, receive speeding penalties and ultimately took both of them out of contention for the win. 

pit stalls
Screenshot: NASCAR

Additionally, the corners of pit road are slightly banked like the actual track surface. This presents a unique challenge for tire carriers and changers alike if the driver comes to a stop on the far-right hand side of their pit box. A tire placed improperly can start to roll away on its own. Don’t be surprised to see someone get caught with an uncontrolled tire penalty this weekend. 

Pit Lane Image
Photo: Author

This weekend three drivers and teams will overcome all of these challenges and take home the coveted grandfather clock. Thanks for coming along for the ride. Grab a hot dog and enjoy the show.

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Leo T.
Leo T.
1 month ago

That’s the most comprehensive article about a track I’ve read in a blog. Thanks so much for explaining!

MikeInTheWoods
MikeInTheWoods
1 month ago

Aedan, I had no idea that there was so much engineering going on in NASCAR. My son is going to tour UNC Charlotte next week to see if he wants to pursue motorsports engineering. I’m going to make sure he sees this article.

TOSSABL
TOSSABL
1 month ago

In he decades I’ve lived an hour or so from the track, I’ve never heard of the Grandfather clock: that’s a neat footnote. Once again an interesting and informative article about something which I did not think I cared about.
I’ll second the ‘thanks Aedan’

Hiram McDaniel
Hiram McDaniel
1 month ago
Reply to  TOSSABL

My dad was a member of one of the numerous volunteer fire departments around Martinsville, and one of their fundraisers was working in the she of the concessions stands. 6 hours or so of 10-12 volunteers would net them a decent percentage of the profits. I spent many, many Sundays in my youth roaming around Martinsville Speedway.

The clocks were built in Ridgeway VA, which is where the track is located. Although now much of the production is moved offshore, Ridgeway Clocks has been in business since 1926, grandfather clocks have been their primary product since the early 1960s.

Squirrelmaster
Squirrelmaster
1 month ago

Very informative. I’m not really a NASCAR fan, but reading articles like this give me much greater appreciation for the series. Also, as an engineer, I’m all about the technical details. Thanks Aedan!

Totally not a robot
Totally not a robot
1 month ago
Reply to  Squirrelmaster

Same here. I think I can count with my fingers the number of minutes I’ve spent watching NASCAR. But Aedan’s technical articles are completely my jam and they help me appreciate NASCAR from a technical perspective.

Michael Beranek
Michael Beranek
1 month ago

Great stuff! Not many people understand that NASCAR is, despite appearances, the most sophisticated form of racing. It’s all in the details.

Amberturnsignalsarebetter
Amberturnsignalsarebetter
1 month ago

awesome article Aedan!

Jack Trade
Jack Trade
1 month ago

Fascinating – thank you Aedan! As a relatively-long-time NASCAR fan, I find the more I learn about it, the more I enjoy it.

Is the preferred curb-hugging line a relatively new thing, made possible by better suspension tech/tires compared to the good ole days? Or was it just that there was less margin for error then?

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