2.1 CLUTCH, FLYWHEEL, FLYWHEEL SHIELD Flywheel and clutch meeting SFI Spec 1.3
or 1.4, three-disc maximum, and flywheel shield meeting SFI Spec 6.2 mandatory.
Maximum depth of flywheel shield: 8 5/8-inches (21.9 cm). Clutch must be
manually operated by driver's foot: Electronics, Drag Racing 7 16.05.03
pneumatics, hydraulics, or any other device may in no way affect the clutch
system. Throwout bearing must release all fingers, levers, stages, etc.
simultaneously. Staged or variable release clutches of any description
prohibited. Clutch/bell housing exhaust filter mandatory. See General
Regulations 2.3, 2.5, 2.6, 2.8.
2.2 DRIVELINE Anti-blowback device mandatory. See General Regulations 2.1.
2.3 DRIVELINE COVER Each end of driveshaft must have a full 360-degree cover of minimum 1/16-inch (1.6 mm) steel or 1/8-inch (3.2 mm) aluminum. Rear cover must surround the coupler. Front cover must surround the driveshaft from the back of the reverser to the end of the splicer sleeve in the area of the driver's legs. All covers must be securely mounted to frame, suitable crossmember, reverser or third-member.
2.4 REAREND Aftermarket full-floating or live axle assembly mandatory. Maximum (numeric) gear ratio 4.30 for screw-type supercharger equipped; 4.58 for Roots-type supercharger equipped cars.
2.5 TRANSMISSION OEM or OEM-modified transmissions prohibited. Transmission limited to 2 units (3 forward speeds). Overdrives prohibited. Final drive ratio must be 1:1. Clutch hold-down device recommended on all cars. Reverser mandatory. Automated shifters and/or timertype shifting devices prohibited, each individual shift must be a function of the driver. Air shifter bottles must be stamped as meeting DOT 1800 pound (124 bar) rating, must be permanently mounted (hose clamps or tie wraps prohibited).
2.6 TRANSMISSION SHIELD A one-piece ballistic shield covering all units mandatory. Must meet SFI Spec 4.1. See General Regulations 2.13.