NASCAR issued a bulletin to teams with updates to the 2016 Sprint Cup Rule Book. Most are clarifications or updates as opposed to anything new.
Among the items listed:
— Teams may change the radiator during Speedweeks at Daytona. The radiator may be changed after completion of the 150-mile qualifying races and must be completed before the final practice for the Daytona 500.
— Teams must use the same rear end differential assembly at all events except: All road course events, events at Martinsville Speedway, the Daytona 500, the Sprint Showdown and the Sprint All-Star Race. If the rear end differential assembly is changed before a race at any other event, the team will have to start at the rear of the field.
— NASCAR listed how many sets of tires teams are permitted for races. Teams will be allowed one fewer set of tires than last year at seven venues, representing 11 races. Those events are Daytona 500 (nine sets of tires for race), Phoenix (nine), Bristol (nine), Richmond (10), Coca-Cola 600 (12), Charlotte fall race (10) and Michigan (eight). NASCAR is allowing teams to have an extra set of tires compared to last year for races at Atlanta (13 sets this year) and Kentucky (10 sets).
— NASCAR listed the tire codes for the first 12 Cup events this season. There will be new left- and right-side tire codes for races at Atlanta Motor Speedway, Las Vegas Motor Speedway, Phoenix International Raceway, Auto Club Speedway, Texas Motor Speedway, Richmond International Raceway, Kansas Speedway and Dover International Speedway. The changes are related to the low downforce package that debuts this season. Tracks that will have the same tire code in Cup are Daytona International Speedway, Talladega Superspeedway, Martinsville Speedway and Bristol Motor Speedway. The tire codes for other tracks have not been set.
— NASCAR listed the pit road speed limit for each track. The pit road speed limits are:
Atlanta Motor Speedway (45 mph)
Auto Club Speedway (55 mph)
Bristol Motor Speedway (30 mph)
Charlotte Motor Speedway (45 mph)
Chicagoland Speedway (45 mph)
Darlington Raceway (45 mph)
Daytona International Speedway (55 mph)
Dover International Speedway (35 mph)
Homestead-Miami Speedway (45 mph)
Indianapolis Motor Speedway (55 mph)
Kansas Speedway (45 mph)
Kentucky Speedway (45 mph)
Las Vegas Motor Speedway (45 mph)
Martinsville Speedway (30 mph)
Michigan International Speedway (55 mph)
New Hampshire Motor Speedway (45 mph)
Phoenix International Raceway (45 mph)
Pocono Raceway (55 mph)
Richmond International Raceway (40 mph)
Sonoma Raceway (40 mph)
Talladega Superspeedway (55 mph)
Texas Motor Speedway (45 mph)
Watkins Glen International (40 mph)