Jeff Purvis

Common Type

1. Speedway : Speedway or Intermediate tracks make up the bulk of the NASCAR schedule. Those are defined by any track greater than one mile in length, with the exception of both Daytona and Talladega.
2. Road Course : Road course tracks are not typical ovals. In fact, they aren’t ovals at all. Road courses add right turns into the mix, with longer courses that often wind through the surrounding scenery. Circuit of The Americas, Road America, Watkins Glen and Sonoma are the road courses the Cup Series currently visits. The Charlotte Roval and Indianapolis Road Course are a combination road course/oval track.
3. Short : Short tracks are less than 1 mile in length – count Martinsville Speedway (.526 miles), Bristol Motor Speedway (.533 miles) and Richmond Raceway (.75 miles) in that category for the Cup Series.
4. Superspeedway : Daytona International Speedway (2.5 miles) and Talladega Superspeedway (2.66 miles) are the only two tracks NASCAR defines as "superspeedways." Both are humungous ovals, and both have used restrictor plates in the past (and currently tapered spacers) to keep the speed of the car in check.

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Accupredict Track Types

Flat

Flat Tracks feature minimal banking, making them unique in NASCAR. These tracks require drivers to rely more on skill and precision rather than speed. Key examples include Martinsville, New Hampshire, Phoenix, and Richmond. Performance on flat tracks is typically influenced by a driver's ability to handle tight turns and maintain consistent lap times.

Front and backstretches range from 0° to 9°.

Turns range from 7.5° to 14°.

Large Oval

Large Oval Tracks include tracks that do not fit neatly into the traditional oval categories but share similarities with larger, more challenging circuits. These tracks offer a mix of speed and technical driving. When first developed, the Accupredict Tracks in this category included Atlanta (prior to the 2021 reconfiguration), California (Auto Club Speedway prior to its reconfiguration to a Short Track), Chicagoland (now defunct), Michigan, Las Vegas, Kansas, Kentucky (now defunct), and Texas. These tracks require a blend of strategic racing and high-speed performance.

Front and backstretches range from 5° to 12°.

Turns range from 17° to 24°.

Road Course

Road Course Tracks are unique in NASCAR, incorporating both left and right turns, as well as elevation changes and technical sections. This diversity demands excellent car handling and driver skill. Prominent road courses include Watkins Glen and Sonoma. Road courses challenge drivers with a combination of speed, precision, and adaptability.

Restrictor Plate

Restrictor Plate Tracks are designed to reduce speeds and increase safety by using restrictor plates to limit engine power. These tracks, such as Daytona, Talladega (and now also Atlanta), are known for high-speed pack racing and frequent lead changes. Success on restrictor plate tracks depends on drafting skills, strategic positioning, and the ability to avoid multi-car accidents.

Front and backstretches range from 0° to 5°.

Tri-Oval is 18°

Turns range from 28° to 33°.

Steep

Steep Tracks have significant banking, allowing for higher speeds and better grip in the turns. This banking helps cars maintain higher cornering speeds, making races on these tracks particularly thrilling. Notable steep tracks include Bristol, Dover, and Darlington. Drivers' success on steep tracks often hinges on their ability to handle high-speed turns and maintain control under intense conditions.

Front and backstretches range from 2° to 9°.

Turns range from 18° to 30°.

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Track Size Types

Intermediate

These courses are 1 to 2 miles (1.6 to 3.2 km) long, particularly 1.5 miles (2.4 km). Early in NASCAR history, this size was rare. By 1990, only five existed. Two - Marchbanks Speedway (1.4 miles) and Trenton Speedway (1.5 miles) - were demolished, leaving Charlotte Motor Speedway, Atlanta Motor Speedway, and Darlington Raceway. Most others were built after 1994, often called "cookie cutter" tracks due to perceived similarities.

In 1992, Charlotte added lights for night racing, now common at these tracks. Intermediate tracks typically have moderate to steep banking. Most modern tracks used in NASCAR balance high speeds with good sightlines, especially 1.5-mile tri- and quad-ovals.

Intermediate tracks were designed for stock cars. They remain a key part of the NASCAR racing calendar.

Mile Oval

A 1-mile (1.61 km) oval is common in oval track racing. Exact measurements can vary slightly. Most are flat-banked, except for Dover.

Historically, many 1-mile dirt ovals were used by stock cars and champ cars until the early 1970s. These tracks often originated from harness racing and were called "Fairgrounds" tracks, like Arizona, California, and Michigan State Fairgrounds. The Milwaukee Mile, originally for horse racing, is the oldest oval race track.

Only three 1-mile tracks remain on the NASCAR calendar: Phoenix, Loudon, and Dover.

Road Course

NASCAR road course tracks are unique, as they incorporate both left and right turns, unlike the traditional oval tracks. These tracks typically range from 2 to 4 miles (3.2 to 6.4 km) in length. Early in NASCAR history, road courses were less common, but they have gained popularity over the years.

Notable NASCAR road courses include Watkins Glen International, Sonoma Raceway, and the Charlotte Motor Speedway Roval. Watkins Glen and Sonoma have been mainstays in the NASCAR calendar, providing challenging layouts with elevation changes and technical turns. The Charlotte Roval, introduced in 2018, combines elements of the traditional oval with an infield road course, offering a unique hybrid experience.

Road courses require a different skill set, emphasizing braking, handling, and precision. These tracks add variety to the NASCAR schedule, challenging drivers with diverse racing conditions. Road course races often feature strategic pit stops and tire management, making them exciting and unpredictable events in the NASCAR season.

Short Track

A short track is an oval less than one mile (1.6 km), often 0.5 miles (0.8 km) or shorter. Drivers usually start their careers on these tracks, nicknamed "bullrings" for their short length and fast action. Professional NASCAR races on short tracks often cover 500 or 400 laps. Many have lights for night races.

Short tracks are crucial for NASCAR's feeder series. Three are in the Cup Series: Bristol, Martinsville, and Richmond. Tracks with potential for future Cup races include Iowa Speedway (built in 2006), Nashville Fairgrounds Speedway (used until 1984), and Memphis Motorsports Park (hosted Busch Series races until the 2000s).

Street Circuit

A street circuit uses temporarily closed public roads in cities or towns for racing. Temporary facilities like paddocks and grandstands are installed for the event and removed afterward. The track surface is often bumpy with limited grip, and run-off areas are usually non-existent, making mistakes costly.

The Chicago Street Course, a 2.140 mi (3.444 km) circuit in Grant Park, is a prime example. Hosting the NASCAR Cup Series and Xfinity Series, it debuted on July 1–2, 2023. Initially a conceptual track on iRacing, it became a real-life circuit with roads closed days in advance and reopened within two weeks post-race. It is scheduled to host races again in 2024 and 2025.

Superspeedway

A superspeedway is an oval track of 2 miles or longer. The most famous are Indianapolis Motor Speedway and Daytona International Speedway, both 2.5 miles. Built in 1909 and 1959, they host the Indianapolis 500, Brickyard 400, and Daytona 500.

Talladega Superspeedway, 2.66 miles, holds the fastest stock car speed record. Daytona and Talladega use restrictor plates to reduce speeds due to steep banking.

Other NASCAR superspeedways include Michigan International Speedway, Auto Club Speedway, and Pocono Raceway. Auto Club and Michigan are similar to intermediate tracks; Pocono and Indianapolis are long, flat tracks.

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Track Shape

D-Shaped Oval

The tri-oval shape, conceived by Bill France, Sr. during the planning of Daytona, became popular during the construction booms of the 1960s and 1990s. It provided fans with superior sightlines, allowing an angular perspective of cars approaching and moving away, unlike traditional ovals that required fans to look back and forth like a tennis match. The tri-oval shape prevents the need to "lean" to see oncoming cars and creates more forward sight lines. However, modern tri-ovals are often called "cookie cutters" due to their nearly identical shapes and racing styles.

A variation of the tri-oval is the "D-shaped oval." Similar to a tri-oval, a D-shaped oval has a straight backstretch but features a long, sweeping frontstretch, giving it a layout resembling the letter D. This shape originated with Michigan International Speedway and Texas World Speedway, built in the 1960s. Initially used for superspeedways, this design now appears in some short tracks as well. For instance, Richmond Raceway was rebuilt in 1986 from a 0.542 mi stadium oval to a 0.750 mi D-shaped oval. The Iowa Speedway, explicitly designed as a D-oval, opened in 2006 and is another famous example of this layout.

Egg-shaped Oval

An egg-shaped oval has non-parallel straights, resulting in curves with different radii. These tracks, often with unique shapes, flat corners, and hard braking zones, produce driving characteristics similar to road courses. Darlington Raceway, the most famous example, was built this way to avoid disturbing an existing minnow pond. Other tracks may share these irregular features, enhancing the driving challenge.

Paper Clip Oval

A typical oval track consists of two parallel straights connected by two 180° turns. While many ovals follow this symmetrical design, asymmetrical tracks like the "paper clip" oval are also common.

The paper clip oval is a sub-classification of the traditional oval shape. It features two long straights connected by two sharp, tight-radius turns, resembling a paper clip. These tracks are challenging, with little banking, making the turns slow and tight to maneuver. This layout is classic for short tracks and some mile ovals. Most short tracks are paper clips, but some 1-mile tracks also have this shape.

Quad-oval

The tri-oval shape, conceived by Bill France, Sr. during the planning of Daytona, became popular in the 1960s and 1990s. It provides fans superior sightlines, allowing an angular perspective of cars approaching and moving away. This design eliminates the need for spectators to look back and forth, as required by traditional ovals, and provides more forward sight lines. However, modern tri-ovals are sometimes called "cookie cutters" due to their similar shapes and racing styles.

A quad-oval is a variation of the tri-oval, featuring a "double dogleg." It offers similar sightlines and layout, with the key difference being that the start-finish line falls on a straight section rather than along a curve. This shape has become a signature for Speedway Motorsports, which owns all major quad-ovals in the United States. The Calder Park Thunderdome in Melbourne, Australia, is also a quad-oval, though often referred to as a tri-oval since its opening in 1987. Rockingham Speedway is a unique case, as it can be interpreted as a D-oval, tri-oval, or quad-oval, with its asymmetrical front line featuring two faint kinks and the start-finish line next to the second kink.

Road Course

NASCAR road course tracks are unique, as they incorporate both left and right turns, unlike the traditional oval tracks. These tracks typically range from 2 to 4 miles (3.2 to 6.4 km) in length. Early in NASCAR history, road courses were less common, but they have gained popularity over the years.

Notable NASCAR road courses include Watkins Glen International, Sonoma Raceway, and the Charlotte Motor Speedway Roval. Watkins Glen and Sonoma have been mainstays in the NASCAR calendar, providing challenging layouts with elevation changes and technical turns. The Charlotte Roval, introduced in 2018, combines elements of the traditional oval with an infield road course, offering a unique hybrid experience.

Road courses require a different skill set, emphasizing braking, handling, and precision. These tracks add variety to the NASCAR schedule, challenging drivers with diverse racing conditions. Road course races often feature strategic pit stops and tire management, making them exciting and unpredictable events in the NASCAR season.

Rounded-off Rectangle

A typical oval track consists of two parallel straights connected by two 180° turns, usually labeled as four 90° turns. While many ovals follow this symmetrical design, asymmetrical tracks are not uncommon.

The "rounded-off rectangle" is a unique but now uncommon track shape. It resembles a rectangle with two long straights, two short straights, and four separate turns. Unlike traditional ovals with two continuous 180° radii, this shape has four distinct 90° curves, featuring "short chutes" between turns one and two and between turns three and four.

Homestead-Miami Speedway was originally designed as a rounded-off rectangle and called a "mini-Indy." However, its 1.5-mile length and sharp corners made it noncompetitive, leading to a reconfiguration into a traditional oval. Indianapolis Motor Speedway remains the only major track with this layout. These tracks are avoided due to poor sight lines, slow corners, and dangerous impact angles, though they are used by private manufacturers' test tracks. The only major short track with a rectangular layout resembles a rounded-off square with nearly identical straights and turns.

Rounded-off Triangle

A typical oval track consists of two parallel straights connected by two 180° turns, usually labeled as four 90° turns. While many ovals follow this symmetrical design, asymmetrical tracks are not uncommon.

The "rounded-off triangle" is a rare layout in oval courses. Unlike traditional ovals, this shape features three distinct, widely varying turns. Pocono Raceway is the prime example, with its unique triangular design, often described as an oval that drives like a road course. This layout is popular outside the United States, offering a unique challenge compared to typical oval tracks.

Stadium Oval

A typical oval track consists of two parallel straights connected by two 180° turns. Although most ovals have two radii curves, they are often labeled as four 90° turns. While many ovals follow a traditional symmetrical design, asymmetrical tracks are not uncommon.

A sub-classification of the traditional oval shape is the "stadium" oval. Unlike the paper clip oval, the straight sections are relatively short compared to the curves, making it closest in form to a circle. The curves usually have high banking, offering a unique challenge.

Tri-oval

The tri-oval, conceived by Bill France, Sr. during the planning of Daytona, became popular during the construction booms of the 1960s and 1990s. Its design offers superior sightlines, allowing fans in the grandstands an angular perspective of the cars approaching and moving away. This eliminates the need for fans to look back and forth like in traditional ovals, providing more forward sight lines.

A tri-oval resembles an isosceles triangle with rounded corners. The backstretch is typically straight, while the main straightaway, housing the pit area and grandstands, features a "tri-oval" curve, often considered a fifth turn. This skewed main stretch enhances visibility for spectators. Most tri-ovals place the start-finish line at the apex of the tri-oval curve. However, tracks like Talladega and Walt Disney World Speedway have the start-finish line on the straight between the curve and turn one. Despite their advantages, modern tri-ovals are sometimes called "cookie cutters" due to their nearly identical shapes and racing styles.