a. The minimum wheel base will be 103”-inches with a maximum wheelbase of 105”-inches.
b. Frames fabricated using square tubing must be a minimum of 2”-inches x 2”-inches or approved rectangular magnetic steel with a minimum material thickness of .083”-inches.
c. Frames fabricated using round tubing must be a minimum of 1.75” Outside Diameter magnetic steel tubing, 4130 Chrome Moly or DOM with a minimum material thickness of .083”-inches.
d. Rear bumpers that are stubbed may only extend a maximum of 8”-inches beyond the frame. Any stubbed rear bumper that extends further than the maximum of 8”-inches must be formed and directed 8”-inches toward the front of the car.
e. External rub rails will not be permitted.
f. All cars must be equipped with a tow hook and/or strap for the purpose of towing.
g. All battery supports and/or mounts must be secure and braced in two (2) horizontal positions and one (1) vertical position.
h. Any frame built on or after January 1st, 2006, must have the builder’s unique serial number plate prominently attached to the left side roll cage upright. The plate must be welded in place. All characters on the plate must be a minimum of ½”-inch in height and the serial number must not exceed 8 characters.
B. Roll Cage
a. All cars must have a roll cage fabricated from a minimum of 1-1/2” outside diameter with .065”-inch thick seamless magnetic steel tubing.
b. The side roll bars and/or door bars must extend into the door panels.
c. A minimum of three (3) 1-1/2” outside diameter bars .065”-inch in thickness must be utilized on the left side of the car in the door area.
d. Any of the bars that are utilized for the top portion of the roll cage, including, but not limited to the front and rear hoops, the top hoop and the uprights, must extend a minimum of 1”-inch above the driver’s helmet.
e. All new frames and/or roll cages built on or after January 1st, 2006 an additional vertical side brace is required on the left side in vertical alignment with the steering wheel.
C. Driver Side Intrusion Plate
a. A minimum 1/8″ (.125”) thick magnetic steel intrusion plate on the driver’s side door bars is mandatory.
b. Approved installations:
i. Welded plates- Individual plates between door bars are permitted but must be weld around the perimeter of each opening. Minimum area covered is 16inches by 26 inches.
ii. A minimum of 16” x 26” plate bolted to fabricated 1/8” (.125”) magnetic steel tabs, welded securely to the chassis, using a minimum of eight (8) x 3/8” Allen button head bolts. A minimum of three (3) fabricated 1/8” (.125”) magnetic steel tabs and 3/8” Allen button head bolts required across top of the intrusion plate, a minimum of three (3) fabricated 1/8” (.125”) magnetic steel tabs and 3/8” Allen button head bolts required across the bottom of the plate, and one (1) fabricated 1/8” (.125”) magnetic steel tabs and 3/8” Allen button head bolt in each in the middle front and middle rear of intrusion plate.
iii. A minimum of 16” x 26” plate bolted to a minimum of six (6) approved-design door bar clamps using the included 12 x 1/2” Allen button head bolts per the manufacturer’s specification. A minimum of three (3) approved-design door bar clamps and the included six (6) x 1/2” Allen button head bolts required across top of the intrusion plate and three (3) approved-design door bar clamps and included six (6) x 1/2” Allen button head bolts required across bottom of intrusion plate. Vendor and part number must be clearly labeled on part.
iv. Current approved-design door bar clamps (as of December 1, 2018) – in order of submission:
1. Bicknell Racing Products – Part Number: BRP 954
2. Wehrs Machine & Racing Products – Part Number: WM397
3. Allstar Performance – Part Number: ALL4198
D. Weight and Ballast
a. The total weight of the car with the driver will be:
i. A minimum of 2,350 lbs. as weighed on the track scales for a car with any engine block.
ii. There will be a 1-pound per lap burn off for feature events only. (Does not apply to DIRTcar sanctioned events)
b. Additional added weight(s) up to 50 lbs. must be positively fastened by two 2½-inch, minimum grade 5 bolts with a minimum of two (2) weight clamps. Threaded rods will not be permitted. All weights must be painted white and clearly labeled with the car number on it.
c. Additional added weight(s) must be securely attached to the frame below the body decking.
d. Frame is defined as the steel welded structure only.
e. Any part that moves or is not a fixed component to the steel frame structure may not be used for any additional weight attachments.
f. Additional added weight(s) attached to the rear bumper and/or outside the frame will not be permitted.
g. Any car that loses any weight/ballast during an event may be subject to a penalty.
h. Pellet-type and/or liquid-type weight/ballast will not be permitted.
i. Driver operated weight adjustment, ‘weight jacking’ devices will not be permitted.
j. The scale(s) used for the event, provided by the series or the track will be considered the official scales for the event.
k. Scale(s) will be available for all teams to verify its car weight and determine the scale weight.
l. In the event of a car not meeting the required overall weight, Officials may allow a car to re-weigh up to (2) two additional times by removing the car from the scale(s) and repeating the weighing procedure. If a car is allowed to re-weigh the overall weight of the car recorded during the final weighing procedure will be the “official” weight of the car.