Motorsport.com has obtained a copy of the proposed modifications for next season. Some of the highlights include:
1. Testing policy – An update to the National Series testing policy which would allow drivers returning to the sport following a medical absence to have an extra test under the discretion of the sanctioning body.
2. Spoiler Size – For non-superspeedway events, the spoiler height will be reduced from 3.5 inches to 2.375 inches, further reducing downforce.
3. Mandatory Roof Hatches at Superspeedways – Roof hatches will remain optional at other race tracks.
4. Energy Absorbing Material added to the toe board in the driver’s cockpit – NASCAR-approved toe board will be mandatory at Superspeedways.
5. Frame Changes – In an effort to restrict movement of the rear axle during competition, NASCAR is mandating change to the main frame assembly, truck trailing arm crossmember assembly, track bar mount and truck trailing arm on rear suspension, arm spacer and pinion angle shim.
6. Restrictor Plates – For superspeedways, the initial restrictor plate hole size will decrease from 57/64 to 7/8 inch.
See more at Motorsport.(10-14-2016)
UPDATE: A further reduction of downforce and the implementation of additional safety developments highlight the 2017 NASCAR premier series rules package announced by sanctioning body officials on Friday at Kansas Speedway. Aerodynamic adjustments similar to those in place for races at Kentucky Speedway and Michigan International Speedway in 2016 form the framework for the 2017 performance platform. However, slight modifications to the overall base package have been made. According to officials, the 2017 race package will include:
‘ Rear spoiler dimensions for all non-restricted events will be 2 3/8 inches x 61 inches. Current spoiler dimensions are 3 1/2 x 61; for the Kentucky and Michigan races, the dimensions were 2 1/2 x 53 inches.
‘ Splitter measurements for the 2017 package will be the same as those for the 2016 Kentucky and Michigan races, with a 3-inch reduction in the outboard (side) areas;
‘ A tapered rear deck fin;
‘ Net rear steer setting of zero.
The aero changes are the next evolution of the platform first rolled out for select events in 2015. Mandatory for 2016, those changes reduced downforce (the pressure exerted on a vehicle as it moves through the air) from 2,700 pounds to approximately 2,000 pounds. The 2017 package is expected to reduce downforce by approximately 500 pounds, landing in the 1,500-pound range. Safety enhancements, which include strengthening the interior driver compartment, will be mandatory for superspeedway events at Daytona International Speedway and Talladega Superspeedway and optional at the remaining venues for 2017. The aero package for superspeedway races at Daytona and Talladega will remain unchanged, although there will be a decrease in restrictor plate size (from 57/64ths to 7/8ths of an inch) to combat increasing speeds at the two tracks.(NASCAR.com)
