This unofficial utility based on the 2015 rules will help you class your vehicle. Select your base class and any modifications that apply. To see what base class your vehicle belongs in, see NASA-X Classes.

BTM = Base Trim Model
OEM = Original Equipment Manufacturer

Base Points

No additional points NO POINTS
* Add 7 Points +7
** Add 14 Points +14

Tire Points

DOT-approved R-compound tires: BFG R1S, Goodyear Eagle RS AC (auto-cross), Hoosier A7, Hankook Z214 (C90 & C91 compounds only), Hoosier Wet DOT (if used in dry conditions) +22
DOT-approved R-compound tires: Hoosier A6 +17
DOT-approved R-compound tires and those with a UTQG treadwear rating of 40 or less not listed otherwise in these rules: BFG R1, Goodyear Eagle RS, Hankook Z214 (C71, C70, C51, C50), Hoosier R7, Kumho V710 +10
DOT-approved R-compound tires: Hoosier SM7 +9
DOT-approved R-compound tires: Hoosier R6, Hoosier SM6 (note: Continental Tire Sportscar Challenge EC-Dry tires (225, 245, 275) OK) +8
DOT-approved R-compound tires: Toyo Proxes RR, Hankook TD +7
DOT-approved R-compound tires and those with a UTQG treadwear rating over 40 (examples: Maxxis RC-1, Kumho V700, Michelin Pilot Sport Cup & MPS Cup 2, Nitto NT01, Pirelli PZero Corsa, Toyo R888, Toyo RA-1, Yokahama A048, etc.) +6
DOT-approved (non-R-compound) tires with a UTQG treadwear rating of 120-200 (examples: BFG g-Force Rival, Toyo R1R, Dunlop Direzza Sport Z1 Star Spec, Bridgestone Potenza RE070, Kumho Ecsta XS, Yokohama Advan A046 & Neova AD08, Hankook R-S3) +2
Non-DOT-approved racing slicks +30
DOT-approved (non R-compound) tires


Weight Reduction Points

• Maximum of two hundred and fifty (250) lbs. of added ballast — All ballast must be of solid material (no fluids or shot pellets) and safely secured in any location on the vehicle approved by NASA technical inspectors. The preferred method is to use at least one (1) 3/8-inch grade-5 bolt, two (2) “fender” washers and a locking nut system for every fifteen (15) pounds of weight. NO POINTS

OEM jack and spare tire removal NO POINTS
Floormat removal (required) NO POINTS

Engine/Drivetrain Points

(Increased Displacement %) = ((Current Discplacement) / (OEM Displacement) -1) * 100

Added dry sump oil system +7
Added and motor is lowered from OEM/BTM location+14

Naturally Aspirated +3
Forced Induction +10

Non-OEM/BTM, deleted, or modified/ported throttle body +2
Independent throttle bodies +4

4 Cylinder +1
6 Cylinder +2
8 Cylinder +3
12A and 13B Rotary +2
Other Rotaries +3

Non-OEM/BTM or modified carburetor, fuel rail, fuel injectors, fuel pump(s), and/or fuel pressure regulator +2
Fuel pump only if using OEM/BTM fuel and timing maps, sensor inputs and ignition timing NO POINTS

Replacement pulley for OEM/BTM supercharger or replacement of any pulley that affects OEM/BTM supercharger speed +4
Modification of the OEM/BTM air intake/box, air filter location, air piping to the turbo/supercharger/intercooler/throttle body/carburetor, or hood/fascia/fender air inlet(s), outlets, or vents +1
Air filter upgrade (without modification of the air filter housing or air intake system) NO POINTS
Aftermarket boost controller or modification/alteration of OEM/BTM vacuum lines that serve to function as a boost controller +4
Aftermarket or modified wastegate actuator, wastegate, or vacuum lines that serve to control the wastegate actuator function or increase peak boost +3
Added aftermarket intercooler +7
Non-OEM/BTM or modified intercooler +4
Water injection system +6

Modification or porting of the exhaust manifold +2
Aftermarket or modified header +2
Non-OEM/BTM or modified exhaust piping, resonators, or mufflers downstream from the header, exhaust manifold, or turbo +2
Removal, upgrade, or modification of catalytic converters +1

Non-OEM/BTM sequential (semi-automatic) or dog-ring (non-synchromesh) transmission (includes altered gear ratios) +7
Upgrade number of forward gears in transmission or altered gear ratios +3
Final drive ratio modification +3
Added paddle/electronic shift +3
Added limited slip differential or welded/locked differential +3
Changed or modified limited slip differential (or welded/locked OEM/BTM LSD) +1
Added traction control +3
Relocation of engine/transmission between 1 and 10 inches of the OEM/BTM location +7
Modification/upgrade from a fixed to a floating rear axle +3
Modification/upgrade/replacement of flywheel or torque converter with any lightened or non-OEM/BTM part +1
     (note: balancing/resurfacing a stock flywheel is still +1)

Modified or non-OEM/BTM replacement camshafts, rocker arms, push rods, or cam timing gears (for one or more) +6
Valve size change, modified, ported or polished OEM/BTM head (other than simple shaving of the head only) +6
De-stroked engine +4
Replacement pulleys (other than for supercharger) +1
Non-electrical fan removal +1

Suspension/Brakes/Chassis Points

Non-OEM/BTM shocks/struts/dampers with an external reservoir or more than two ranges of adjustment +10
Non-OEM/BTM shocks/struts/dampers with a fixed reservoir without a connecting hose OR with shaft diameter 40mm or greater +7
Non-OEM/BTM or modified/re-valved shocks/struts/dampers +3

Non-OEM/BTM, modified, or relocated brake calipers and/or brake caliper brackets +2
Brake duct addition or modification, including electric fans (water sprayers are illegal) NO POINTS
Non OEM/BTM brake pads and rotors NO POINTS
Brake lines, boosters, proportioning valves, and master cylinder modification or replacement. NO POINTS
Emergency brake removal NO POINTS

Non-OEM/BTM or modified coil springs, leaf springs/spacers/brackets, or torsion bars +2
Conversion of torsion bar/leaf spring suspension to coil spring and strut/shock suspension +2
Add, replace, remove, or modify anti-roll bars or end links +2
      (swaybars may have spherical joints on the end links and/or relocation of the mounting points without point assessment)
Replace or modify control arms or RWD/AWD rear trailing arms +4
Relocation of front suspension mounting points +6
Relocation of rear suspension mounting points +6
Changing the mounting orientation/design of the OEM/BTM shock and/or spring perch to invert them +1
Using the alternate control arm mounting location on cars equipped OEM/BTM with multiple choices +6
Changing the orientation or design of an OEM/BTM mounting point or pick-up point of a control arm for a panhard bar trailing arms +1
Replaced or modified K-members that change the location of the lower control arms +8
Tubular K(cross)-members that do not change the location of the lower control arms +2
Bump steer kits or shimming of the steering rack +2
Alteration of ball joints/dive angles +2
Add panhard rod or Watt’s link +4
Replace or modify an OEM/BTM panhard rod or Watt’s link +2
Add torque arm +4
Replace or modify an OEM/BTM torque arm +2
Increase in track width greater than 4 inches +6
Non-OEM/BTM rear trailing arms on FWD vehicles +1
Non-OEM/BTM rear control arms on FWD vehicles +1
Metallic replacement suspension bushings (Heim joints/spherical joints) +3
Add front lower stress/arm brace +1
Add front strut tower bar +1
Add rear strut tower bar +1
Add a third (or more) attachment point to front or rear strut tower bar +1
Add or modify other chassis stiffening devices or fabricated parts +3
Non-OEM/BTM driver/cockpit adjustable sway bar or suspension settings +4
Seam or stitch welding of the body/chassis +5

Rollbar/Cage Points

One or more bars that penetrate the front bulkhead/firewall +2
One or more bars that are welded to the chassis anywhere farther than 6″ from the end of one of the above 6 or 8 listed tubes where it terminates at a plate +6


No-Points Modifications
  • Rolled fender lips
  • Flared fenders
  • Sun/moonroof removal and cover roof hole.
  • Battery replacement/lightweight battery/dry cell
  • Air bag removal
  • OEM/BTM jack and spare tire removal
  • Floor mat removal (required)
  • Wheels, studs, spacers, wheel bearings replacement/upgrade, hub modification/replacement, all with less than 4 inches of total track width gain, also axle modification or replacement (unless otherwise assessed points above).
  • Simple camber, caster, and toe adjustment by any method that does not alter suspension mounting points (unless the modification used is otherwise assessed points above) – such as control arm, ball joint, and relocated mounting point modifications). Slotting of the OEM/BTM bolt holes and removal of material from the top surface of the OEM/BTM strut/shock tower to the extent necessary to allow simple camber/caster adjustment is permitted. Bolt on camber/caster plates are not assessed points.
  • Ride height adjustment (must still take points for springs and torsion bars above)
  • Air filter upgrade (without modification of the air filter housing or air intake system)
  • Radiator upgrade/shrouding/fascia modification (drilled or cut holes/slots) that only provides increased airflow to the radiator or oil/transmission coolers (without aerodynamic or engine air intake improvement)
  • Starter motor replacement
  • Alternator replacement (must be able to sustain vehicle operation without a battery
  • Oil systems and coolers other than added dry sump
  • Motor, transmission, and differential mounts and inserts/bushings, replacement/upgrade or modification (with up to 1 inch of relocation of the motor/transmission)
  • Engine rebuild with head shave, block decking and 0.020” overbore—provided that compression ratio is not increased by more than 0.5 and displacement is not increased by greater than 1.49%. Forged pistons and internals are legal; however, points must be assessed for de-stroking, and/or increased displacement and compression ratio if greater than the limits listed above. (Note: 0.020” overbore with OEM/BTM rods and overbore pistons will yield an increase in displacement of approximately 1.1% for most engines.)
  • Engine balancing and blueprinting
  • Spark plug wires, plugs, coil, ignition replacement/upgrade
  • Turbo blow-off valve upgrade, modification, or addition
  • Removal of the engine balance shaft and/or balance shaft drive mechanism
  • Replacement of clutch assembly with aftermarket or modified parts
  • Fuel: Any grade of commercially available unmodified gasoline or diesel–all octane levels of retail available race gas are permitted. No “home brewed” methanol/ethanol/alcohol mixtures are permitted. Methanol injection systems are illegal. Fuel additives are prohibited. Retail available E-85 is permitted.
  • Brake duct addition or modification, including electric fans (water sprayers are illegal). Two holes may be cut or drilled out of the front fascia for brake air ducts. Any hole providing improved intake air to the engine will be assessed one (1) point.
  • Non OEM/BTM brake pads and rotors
  • Brake lines, boosters, proportioning valves, and master cylinder modification or replacement.
  • Emergency brake removal
  • Non-metallic replacement suspension bushings
  • Steering wheel replacement
  • Mirror addition, removal, or replacement
  • Gear shifters and shift knob replacement/upgrade
  • Seat harnesses
  • Maximum of two hundred and fifty (250) lbs. of added ballast—All ballast must be of solid material (no fluids or shot pellets) and safely secured in any location on the vehicle approved by NASA technical inspectors. The preferred method is to use at least one (1) 3/8-inch grade-5 bolt, two (2) “fender” washers and a locking nut system for every 15 pounds of weight.
  • Data acquisition systems and/or telemetry
  • Non-OEM/BTM driver’s seat
  • Non-OEM/BTM front passenger seat
  • Relocated battery
  • Adding a hardtop to a convertible and/or removal of convertible soft top/frame
  • Shock tower reinforcement plate (to strengthen tower shock mount location only–no bars)
  • Shock mount replacement/modification (only if already taking points for both shocks and springs)(may raise or lower mount location up to two (2) inches if no horizontal movement.)
  • Accelerator, brake, and clutch pedal modification or replacement.
  • Drive by wire to cable throttle conversion (throttle body must remain identical to OEM/BTM in both size and shape to avoid a +2 throttle body assessment).
  • OEM/BTM ECU/PCM reprogramming via reflashing or replacement/aftermarket ROM chips or simple ROM boards (the OEM/BTM ECU/PCM box/housing and hardware must be used).
  • SAFC or VAFC (Super Air Flow Converter/VTEC Control Air Flow Converter)
  • Non- OEM/BTM sensors or alteration of sensor inputs (such as non-programmable MAF or MAP voltage “clamps”)
  • Steering rack replacement or modification without geometry change (ratio changes)
  • Non-OEM/BTM valve springs and retainers
  • Ignition timing adjustments
  • NACA ducts, air ducts, or air hoses placed in a side window frame solely for purposes of driver cooling
  • Front wing/vent window removal and replacement with Lexan
  • Headlamps, headlight covers,and fog lights may all be removed, and the holes may be covered with material that replicates the shape of the OEM/BTM light/cover, leaving the shape of the OEM/BTM fascia intact. Uncovered holes may be used for brake ducts. Any hole providing improved intake air to the engine will be assessed one (1) point.
  • OEM/BTM air conditioner system removal with or without A.C. delete pulley.
  • ABS (anti-lock braking system)–Only OEM/BTM systems offered specifically for the car Model as a factory option. No OEM/BTM systems offered for a different car model or aftermarket systems are permitted.
  • EGR, smog pump, charcoal canister and associated vacuum line and hose removal.
  • The addition of a second fuel pump inside an OEM/BTM fuel tank, serving only as a transfer pump to help prevent fuel starvation, that is not connected to the fuel line providing fuel to the engine in any way, and does not increase the maximum fuel flow or pressure provided by the OEM/BTM fuel pump.
  • Add, replace, or modify front fascia or air dam
  • Add, replace or modify a single front splitter/spoiler/wing/foil
  • Add, replace, or modify rear wing or spoiler
  • Add or modify canards/winglets
  • Add or fabricate any flat bottom/belly tray
  • Add rear diffuser, replace or modify OEM/BTM rear diffuser, rear bumper cover, or rear “fascia”
  • Add rear vertical panels in any location
  • Add or modify side skirts
  • Add vortex generator to roof, rear window, or rear deck lid
  • Front side window frame air dams/diverters (driver and/or passenger side)
  • Tire pressure monitoring systems (TPMS) (Pressure release valves are not permitted.)
  • Header and exhaust piping external wrapping, coatings, and/or paint. (The original OEM/BTM identification markings must still be legible on all exhaust components that are not assessed points.)
  • Oil catch tanks/cans
  • Valve cover replacement or modification
  • Carburetor jetting modification
  • Carburetor vacuum port blocking