Last Updated: NOV. 8, 2019

$5,000 WINNER
$1000 R-UP
$300 SEMIS
$200 1/4s


DESIGNATION: The class designation is LDR. All entrants must display this designation on both sides of their car with car number.

FORMAT: This is a 1/8th mile, heads up category running on a .400 Pro tree with a 32-car qualified field, professional pairing ladder. This is a single power adder class only!

SAFETY: All NHRA/IHRA and Local Track Safety rules apply for car and driver, including the use of an oil retention device and/or engine diaper is MANDATORY. Any competitor causing an oil down that does not have an oil retention device will lose 5 points off their 2018 LDR championship points tally.

BODY: The car must retain its original appearance, profiles and dimensions. No aftermarket one-piece bodies. OEM door jamb and quarter panels must be used. No modified front ends to achieve maximum NHRA/IHRA overhang, must stay within original body dimensions. Must retain factory body lines with removable composite components as in hood, front bumper, front fenders, doors and deck lid. Any beam tripping devices forward of the bumper are prohibited. Aftermarket front bumpers (“Ex. Snowplows or Valances”) cannot have more than 2 inches of overhang over the stock bumper dimensions, failure to abide by this rule will result in disqualification. Aftermarket wings and spoilers are permitted. A hood must be used; scoop or hood must cover entire induction system. Exceptions are throttle bodies or carburetors on naturally aspirated and nitrous oxide assisted engines along with intake manifolds/throttle bodies on boosted engines. Those may protrude through the hood for clearance, if needed. Forward facing hood scoops/turbocharger/supercharger inlets are permitted. OEM/Lexan windows are permitted. Front ends must be within the spirit of the rules and legality is at the discretion of the race director. Firewall must be in the stock location; stock firewall can be modified.

CHASSIS: Door cars only, no pro mod or full tube chassis. Backhalf style cars are permitted. No Wheelie Bars. Any rear suspension is permitted. Factory front frame rails are mandatory, they can be modified and must extend to the center of the front spindle. Aftermarket front K-Members are permitted, must bolt in the factory location. Factory equipped 'bolt-in' subframe cars are permitted an aftermarket bolt-on front end (Ex., Smith Racecraft) for '62-'74 Nova and '67-'81 Camaro/Firebird, must bolt in. Factory wheelbase for year/make/model must be maintained, (+/- 1 inch). A minimum height of 3 inches from the front of the vehicle to 12 inches behind front spindle center line is mandatory. A minimum height of 2 inches for the rest of the vehicle is mandatory (except for oil pan and headers).

BALLAST: Any material used for the purpose of adding to a car’s total weight must be permanently attached to the car’s structure and must not extend in front of or behind the rear of the car’s body. No liquid or loose ballast permitted (water, sandbags, rock, shot bags, metal weights, etc.). Removable weight must be securely mounted to the frame or frame structure by a minimum of two 1/2-inch diameter steel bolts per 100 pounds, or one 3/8-inch steel bolt per 5 pounds. All other weight bars, pucks, etc., must use a minimum two 1/2-inch diameter SAE Grade 8 bolts for attachment per 100 pounds.

ENGINE/POWER ADDERS: The cubic inch limit for any naturally aspirated or power adder combination is 965 cubic inches. All SMALL BLOCK combinations must retain stock bore spacing (4.400) and a maximum 10.000-inch deck height. All engines must have a diaper, belly pan or oil retention device. Nitrous oxide is permitted to run any type multi-stage nitrous system with no restrictions. Nitrous entries must have bottle securely contained in a bottle bracket. Maximum bore spacing for all boosted combinations is 5.000 or less. Turbocharger combinations are limited to a maximum 118mm single turbo or a set of 88mm twin turbochargers. Refer to weight addition/reduction section below for twin turbocharger clarification.

The maximum specifications for a single turbocharged combination are COMPRESSOR WHEEL (inducer-118mm tip to tip, exducer-141mm maximum) and TURBINE/EXHAUST WHEEL (inducer-130mm maximum, exducer-114mm maximum). The maximum specifications for a twin turbocharged combination are COMPRESSOR WHEEL (inducer-88.9mm maximum, exducer dimensions-134mm maximum, measured at the backing plate), (non-extended exducer tip-to-tip measurements may not exceed 135mm), (extended exducer tip-to-tip measurements may not exceed 142.5mm) and TURBINE/EXHAUST WHEEL (inducer-113mm maximum, exducer-103.5mm maximum). The maximum diameter of the housing bore at the leading edge of the wheel may not exceed 2mm more than the maximum allowable turbocharger size permitted. Compressor map groove will not exceed .250 of an inch. Turbochargers will be verified by measuring the housing bore at the leading edge of the impeller wheel and must retain the contour of the compressor housing, stepped or clipped compressor wheels are prohibited. Inserts or reducers to achieve inlet or outlet dimensions are prohibited. Any inconsistent modifications to compressor or turbine wheel, blades, hubs, cover or housing beyond accepted commercially available manufacturing process is PROHIBITED. Supercharger combinations are limited to a single centrifugal supercharger at a F3-139 maximum, small block and big block. Maximum size on all twin centrifugal supercharged combinations is base F1X, (F1X-12 is prohibited). Roots superchargers are restricted to a 14-71 maximum. Screw superchargers are permitted on a small block combination only and must be run on a 275 drag radial, no big tire option. Screw superchargers are prohibited on big blocks, 481X and HEMIs. Dual power adders are strictly prohibited across all combinations. All forms of power adders (nitrous, turbochargers and superchargers) must be commercially available to the general public for purchase and use. ELECTRICAL: All entries must be self-starting from inside the vehicle. A master cut-off switch is mandatory on the rear of the car with an on/off sticker. Any electronic ignition system is allowed, see below for weight additions/reductions. Computer/Data Recorders are permitted. EXHAUST: Mufflers or inserts are required on all cars except for turbo cars. Exhaust may exit underneath car or out the front fenders/valance but must not affect timing or staging beams. CO2 SYSTEM AND LINE: The first TWO feet (minimum) of the line coming from the CO2 bottle must be 1/4" plastic line with push-locks. No braided steel lines direct from the CO2 bottle to ensure no nitrous oxide is being used. Braided steel line may be used after the first two feet of plastic/push-lock line to protect the line running through the firewall and/or around exhaust system.

INTERCOOLER: Any intercooler is permitted on gasoline combinations only. Must be securely mounted to chassis or mounts with preferred hardware. Water box must be contained in a safe environment with a top to enclose water/ice during the run. Intercooler combined with a methanol fueled combination is prohibited. TRANSMISSION/DRIVELINE: Any transmission permitted. Any converter permitted. Lock-Up Transmission/Converter setups are permitted on naturally aspirated and nitrous oxide combinations only, prohibited on turbocharger or supercharger combinations. FUEL: Any gasoline, E85 or M1 permitted. M5 is prohibited. No nitromethane or additives. WHEELS/TIRES: Any brand 275/60/15 Drag Radial. Mickey Thompson 295/65/15 Drag Radial (PN: 3558) and Hoosier 295/65/15 DR2 (PN: 17316DR2) will be the legal tire options for the 'big' tire option. Nitrous oxide combinations can run any tire at base weight, no weight penalty on nitrous cars for the big tire. Any 481X/HEMI or Any Hemispherical Headed Combination equipped with single turbocharger, twin turbochargers or centrifugal supercharger(s) must be on a 275/60/15 drag radial, no big tire option for that engine/power adder combination. Must stay on the same tire throughout the entire event.


WEIGHTS: All weights are minimum with driver in car.

NATURALLY ASPIRATED: - Small Block - No Minimum - Big Block - No Minimum NITROUS OXIDE: - Small Block - 2,200 lbs. - Big Block (4.840 Bore, Any Transmission) - 2,550 lbs. - Big Block (5.000 Bore, Any Transmission) - 2,650 lbs. - Big Block (5.000+ Bore, Up to 903 CI, No Lockup Transmission) - 2,800 lbs. - Big Block (5.000+ Bore, From 904-965 CI, No Lockup Transmission) – 2,825 lbs. (+25) - Big Block (5.000+ Bore, Up to 903 CI with Lockup Transmission) – 2,850 lbs. - Big Block (5.000+ Bore, From 904-965 CI with Lockup Transmission) – 2,875 lbs. (+25) TURBOCHARGER: - Small Block, Single Turbo - 2,800 lbs. (-50) - Small Block, Twin Turbo - 2,950 lbs. (-50) - Big Block, Single Turbo - 3,075 lbs. (-25) - Big Block, Twin Turbo – 3,325 lbs. (No Weight Addition for the 295/65/15 Tire) SUPERCHARGER: - Small Block, Roots - 2,650 lbs. - Big Block, Roots – 2,800 lbs. - Small Block, Screw – 3,000 lbs. - Small Block, Single Centrifugal (ProCharger F1 or Equivalent) - 2,725 lbs. (-50) - Small Block, Single Centrifugal (ProCharger F2 or Equivalent) - 2,750 lbs. (-50) - Small Block, Single Centrifugal (ProCharger F3 or Equivalent) - 2,775 lbs. (-50) - Small Block, Twin Centrifugal - 2,950 lbs. (-50) - Big Block, Single Centrifugal (ProCharger F1 or Equivalent) - 2,975 lbs. (-50) - Big Block, Single Centrifugal (ProCharger F2 or Equivalent) - 3,025 lbs. (-50) - Big Block, Single Centrifugal (ProCharger F3 or Equivalent) - 3,075 lbs. (-50) - Big Block, Twin Centrifugal - 3,200 lbs. (-50) WEIGHT ADDITIONS/REDUCTIONS: - 100 lb. Weight Addition for the 295/65/15 ‘Big’ Tire Option, (MT 3558 or Hoosier 17316DR2) except Big Block Twin Turbo combination. - 100 lb. Weight Addition for 481X/HEMI or Hemispherical Headed BBC/BBF except Twin Turbo platform. - 481X, HEMI and Any Hemispherical Headed Engine must be on 275 Drag Radials if power adder is single turbocharger, twin turbocharger or any centrifugal supercharger(s) combination. This rule applies for the screw supercharger, small block combination as well. - 25 lb. Weight Reduction for Non-Extended Tip Compressor Wheel turbochargers on Twin Turbocharged Combination Only (Competitors may be asked to remove compressor cover for verification at any time by technical inspection team) - 25 lb. Weight Reduction for Conventional Headed BBC Combinations on Gasoline. - 50 lb. Weight Reduction for Centrifugal Supercharger Combination on Gasoline. - 50 lb. Weight Reduction for Leaf Spring Rear Suspension.