CLASS RULES AND REGULATIONS
Jr. Pro Stock is a heads-up class designed for naturally aspirated small block and big block engines. Small block engines have a maximum engine size of 470 inches. Big block engines have a maximum engine size of 650 inches. With no major engine limitations. Power adders of any kind i.e. Nitrous, Turbochargers, Superchargers, etc… are strictly prohibited. All entries have a minimum wheelbase of 96 inches and must compete on a bias-ply racing slick.
Note: This set of class rules is presented to all competitors under the assumption that any modiﬁcations not speciﬁcally written within these rules shall be deemed illegal, unless the competitor has the expressed written consent from the Jr. Pro Stock Tech Director.
This class will be an all run heads-up ﬁeld, NHRA Pro Style Ladder on a .400 Pro Tree.
Jr. Pro Stock will feature an 8 car minimum field*
In an effort to provide participants with confidence of competition, only participants who have fully completed the entry process including all required entry fees will be added to the field and featured on the Jr. Pro Stock Contenders List at streetcarsupernationals.com.
*In the event that if by November 1st 7 or fewer cars have entered, the Jr Pro Stock class race will be cancelled and entry fees fully refunded. However, no refunds will be allowed before November 1st or in the event the 8 car minimum field requirement has been met.
SMALL BLOCK BASE WEIGHT (max cubic inch 470)
320 = 2387 + Over 320 add 2.85 lbs. per cubic inch (inline valve head motors only)
340 = 2444 + Over 340 add 2.80 lbs. per cubic inch (inline valve head motors only)
360 = 2500 + Over 360 add 2.75 lbs. per cubic inch
380 = 2555 + Over 380 add 2.70 lbs. per cubic inch
400 = 2609 + Over 400 add 2.65 lbs. per cubic inch
420 = 2662 + Over 420 add 2.60 lbs. per cubic inch
440 = 2714 + Over 440 add 2.55 lbs. per cubic inch
460 = 2765 + Over 460 add 2.50 lbs. per cubic inch
470 = 2815
BIG BLOCK BASE WEIGHT (max cubic inch 640)
440 = 2860 + Over 440 add 2.60 lbs. per cubic inch
460 = 2900 + Over 460 add 2.55 lbs. per cubic inch
480 = 2940 + Over 480 add 2.50 lbs. per cubic inch
500 = 2990 + Over 500 add 2.45 lbs. per cubic inch
520 = 3039 + Over 520 add 2.40 lbs. per cubic inch
540 = 3086 + Over 540 add 2.35 lbs. per cubic inch
560 = 3133 + Over 560 add 2.25 lbs. per cubic inch
580 = 3178 + Over 580 add 2.10 lbs. per cubic inch
600 = 3220 + Over 600 add 2.00 lbs. per cubic inch
620 = 3260 + Over 600 add 1.80 lbs. per cubic inch
640 = 3296
Big Block entries > 640 cubic inches must add a 4lb per cubic inch weight penalty to the 640 cubic inch base weight.
Dry sump oiling systems must add 5% of engine size in pounds.
Spread bore small and big blocks must add 5% of engine size in pounds.
Second carburetor or throttle body must add 10% of engine size in pounds.
Manual Transmission must add 10% of engine size in pounds.
Pontiac, Buick, Olds, and AMC engines may deduct 175lbs.
Mopar big block wedge engines may deduct 125lbs.
Four-link rear suspension must add 5% of engine size in pounds.
Non-class origin tire with automatic transmissions must add 15% of engine size in pounds.
Non-class origin tire with manual transmission must add 25% of engine size in pounds.
Body Style Weight Breaks: Tier 1: Deduct 25 lbs., Tier 2: Deduct 50 lbs., Tier 3: Deduct 75 lbs.
See body style weight break table below for body style assigned tier. If your vehicle is not listed you must run at base + c.i. weight
How to ﬁgure your weight: Weight additions for the above categories are based on taking the engine cubic inch and multiply it by the indicated percentage and converting that number to pounds. IE: 1969 Chevrolet Camaro with 520 cubic inch engine with an automatic transmission (base of 3039). Utilizing category 2 heads add 15% = 78 lbs., dry sump oiling system add 5% = 26 lbs., and non-class origin tires add 15% = 78 lbs., tier 1 body style deduct 25 lbs. for a total add of 157 lbs. (78 + 26 + 78 – 25 = 157) and a total car weight of 3196
REQUIREMENTS & SPECIFICATIONS
REQUIREMENTS & SPECIFICATIONS
Any aftermarket cast iron or cast aluminum block is permitted. Billet blocks are prohibited.
SFI Spec 18.1 balancer is required.
ENGINE MOUNTS & LOCATION
Engine/motor plates and mid-plates are permitted. Engine block and cylinder heads cannot be in contact with the ﬁrewall.
The use of engine coatings is permitted.
Any aftermarket crankshafts are permitted.
Any aftermarket connecting rods are permitted.
PISTONS & PINS
Any aftermarket pistons and pins are permitted.
Any aftermarket piston rings are permitted.
CAMSHAFT DRIVE SYSTEM
Any camshaft drive system is permitted.
Any camshaft is permitted.
Any lifters/lash adjusters permitted.
Any aftermarket cast iron or aluminum cylinder heads are permitted. Cylinder heads must be overhead valve, two valves per cylinder maximum, and single spark plug per cylinder design. BILLET HEADS ARE PROHIBITED. Mopar OEM or aftermarket Hemi heads run same as Chevy or Ford. All Pro Stock style cylinder heads no matter what year produced are Category 3 regardless of brand and are not available for an OEM manufacturer weight break. Pontiac, Buick, Olds, AMC and Mopar cylinder heads must maintain the factory OEM port layout in order to receive a base weight deduction.
Small Block Engines:
• Category 1 heads: run at base weight.
-Under 360 c.i. must add 15% of engine size in pounds
• Category 2 heads: add 15% of engine size in pounds.
-Under 360 c.i. must add 25% of engine size in pounds
• Category 3 heads: add 25% of engine size in pounds.
Small Block Heads: (see weight add section)
• Category 1: Inline valve heads measuring 1.000 or less bottom of intake port to deck.
• Category 2: Inline valve heads measuring 1.001 + bottom of intake port to deck.
• Category 3: All non-inline valve heads. (canted and splayed valve)
Big Block Engines:
• Category 1 heads: run at base weight.
-Under 480 c.i. must add 10% of engine size in pounds
• Category 2 heads: add 20% of engine size in pounds.
-Under 480 c.i. must add 30% of engine size in pounds
• Category 3 heads: add 25% of engine size in pounds.
-Under 480 c.i. must add 35% of engine size in pounds
Big Block Ford & Chevy Heads: (see weight add section)
• Category 1: Heads measuring 1.000 or less bottom of intake port to deck.
• Category 2: Heads measuring 1.001 / 2.000 bottom of intake port to deck.
• Category 3: Heads measuring 2.001 + bottom of intake port to deck.
Note: All cylinder head intake port measurements will be measured after all work has been completed and in ‘’race’’ form.
The lowering of intake runner height to circumvent the port height weight penalties is prohibited.
Any intake manifold permitted.
Any oiling system, vacuum pump and oil pan permitted.
Any cooling system permitted.
Any exhaust system permitted. All exhaust systems must be directed out of body and away from driver and fuel tank.
Any electronic, mechanical or belt driven fuel pumps are allowed. Electronic fuel pumps must shut off with the master electric cut-off switch. Fuel cell must have a pressure cap and be vented to the outside of the body. Front mounted fuel cells must meet SFI Spec 28.1 and be mounted between the frame rails or enclosed in a round tube frame. A round tube frame must be constructed of a minimum of 1 ¼-inch O.D. x .065-inch chrome moly tubing. Artiﬁcial cooling or heating of fuel (i.e., cool cans, ice, Freon, etc.) prohibited. Circulating systems that are not part of the normal fuel pump system are prohibited.
Any aftermarket electronic or mechanical fuel injection may be used. Fuel injector size and or type are unlimited.
Any aftermarket throttle body/bodies permitted. Maximum of two throttle bodies permitted. Throttle bodies that do not mount to a conventional 4150/4500 ﬂange (adapters prohibited) must run dual carburetor weight adder.
Any aftermarket carburetor permitted. Split or inline style carburetors prohibited. Carburetors that do not mount to a conventional 4150/4500 ﬂange (adapters prohibited) must run dual carburetor weight adder.
Throttle control must be operated by the driver’s foot.
Jr. Pro Stock speciﬁed VP Racing Fuels gasoline is the only acceptable fuel allowed. The Jr. Pro Stock Tech Director reserves the right to check gasoline at any time during competition. Failure to pass fuel check is grounds for disallowance of the run during competition and disqualiﬁcation from the event during eliminations.
CLUTCH, FLWHEEL & FLYWHEEL SHIELD
Flywheel and clutch meeting SFI Spec 1.2, 1.3, 1.4, or 1.5 is mandatory. Flywheel shield meeting SFI Spec 6.2 or 6.3 is mandatory. Clutch must be manually operated by the driver’s foot. Electronics, pneumatics, hydraulics, or any other device may in no way affect the clutch system. The throw-out bearing must release all ﬁngers, levers, stages, etc. simultaneously. Staged or variable release clutches are prohibited.
OEM or aftermarket transmissions with a maximum of 5 forward speeds permitted. Clutchless models permitted. Pneumatic, electric, hydraulic, etc. shifters permitted.
Any OEM or aftermarket automatic transmission is permitted. Any torque convertor is permitted. Trans-brakes are permitted. Pneumatic, electric, hydraulic, etc. shifters are permitted.
Any steel, aluminum or carbon ﬁber driveshaft meeting SFI 43.1 spec is permitted.
Any automotive type rear-end is permitted.
BRAKES, STEERING & SUSPENSION: 3
Automated brakes are prohibited. The application and release of the brakes must be a function of the driver. Four wheel hydraulic disc brakes are mandatory. Steel brake lines are mandatory. Brake lines must be out of ﬂywheel and driveline areas. Line-lock is permitted only on the front wheels. One line-lock solenoid with one button is permitted. Any other
electrical, pneumatic, hydraulic, etc. switch in braking system is prohibited. Master cylinder must be mounted above the lower frame rails.
Any automotive type steering system permitted. If competitor is using a commercially available quick disconnect steering wheel, it is mandatory that it meet SFI Spec 42.1.
Coil over shocks are permitted front and rear. Shocks must be stand-alone and may not be adjustable during run via electronic and/or other means. Electronic programmable shocks prohibited. Each vehicle must be equipped with one operating shock for each sprung wheel.
Aftermarket front K-members are permitted. Aftermarket “bolt-in’’ style control arm front end kits can be used as a direct replacement for all American production vehicles where the shock is attached to the upper control arm (from the factory) is permitted without a weight penalty. (Ex. ’62 -‘67 Chevy Nova & ’60 -‘65 Ford Falcon) Modifying the shock/strut tower is permitted.
Stock type, ladder bar and 4-link style suspensions are permitted.
Wheelie bars are permitted with a maximum length of 80 inches.
Stock, unaltered frame rails required in front sub frame from suspension mounting points rearward, frame rails and sub frames forward of the suspension mounting points maybe modiﬁed. Sub frames on uni-bodied cars may be joined under car. After market or custom designed (square or round tubing) rear frame rails permitted from the frame kick up point, after market frame rails forward of the kick up point may be tied into the stock ﬂoor pan. Mini-tubs are permitted.
Entries must retain stock wheelbase dimensions of + or – 1 inch.
A minimum of 3 inches from the front of the vehicle to 12 inches behind front spindle centerline is mandatory. A minimum of 2 inches for the rest of the vehicle is mandatory (except for oil pan and exhaust headers).
TIRES & WHEELS: 5
Any size bias-ply drag racing slick permitted, radial tires are prohibited. Tire tread may not extend outside of the fender.
Class Origin Tire - a true 10.5 racing slick – defined as: bias-ply racing slick with a maximum of 30.5 inches tall, maximum tread width of 10.75 inches as measured on the rim AND as advertised by the tire manufacturer.
Aftermarket racing wheels permitted.
Factory appearing type dash is mandatory. Carpeting is required from seats forward. Factory door panels or door panels made of aluminum or carbon ﬁber are required. Aftermarket steering column is permitted. Aftermarket pedals are permitted.
Window net meeting SFI Spec 27.1 is mandatory.
All vehicles must maintain OEM appearances for their speciﬁc year, make, and model being used. All entries are required to have the OEM body shell intact from the ﬁrewall to the taillight panel. Lightweight body parts are restricted to the following: hood, fenders, bumpers, doors, and trunk-lid/deck-lid. Hood, trunk-lid/deck-lid, and doors must be hinged or be lift off models. Alterations or aerodynamic modiﬁcations are prohibited.
Forward facing and factory OEM hood scoops are permitted.
All entries are required to have an OEM type grille. Covering in front of or behind the grille is permitted and must maintain a ‘’professional appearance’’.
A non OEM ﬁrewall will be allowed provided it is in the stock location and must be one piece of at least .024 or greater steel material fully attached in a in stock location.
FENDER SPLASH PANS
Fender splash pans may be altered.
WINDSHIELD & WINDOWS
All entries are permitted to use Lexan windows.
Driver’s side ﬂoor pan must be steel and welded into place. The remainder of the ﬂoor section can be .024 inch steel or .032 inch aluminum. The use of magnesium is prohibited. Transmission tunnel may be removable and must be made of either .024 inch thick steel or .032 inch thick aluminum.
All entries all permitted to use steel, aluminum, or carbon ﬁber wheel tubs.
All entries are permitted to use rear wing/spoilers. Wing/spoilers are allowed a maximum length of 26 inches. Any adjustments to the wing/spoiler during a run are prohibited.
OEM headlights and taillights for year/make/model of vehicle being used must be intact and operational.
All cars in competition must be painted or wrapped. Advertising graphics are permitted on the body. Class & Competition Numbers: Numbers must be easily visible/legible and located on the front, back, and both side windows.
A maximum of two batteries is allowed.
Any battery operated ignition system and distributor drive system is permitted.
All entries must be self-starting with an on-board starter.
MASTER CUTOFF SWITCH
A master cutoff switch is mandatory.
SUPPORT GROUP: 9
Computer/data recorders are permitted and must standalone and to be only used for information gathering purposes.
BRACKET RACING AIDS
The use of any bracket racings aids such as optical sensors, delay boxes, shutter boxes, throttle stops, etc. are prohibited. The use of any device (electrical or mechanical) that allows a driver to ascertain the position of their vehicle to the starting line is prohibited.
Any device used for the specific purpose of traction control, (Davis Technologies, Racetronics boxes) i.e. control devices that limits the amount of wheel spin to desired amount, devices that maintain a front/rear wheel speed relationship, or any other device that attempts a traction control function other than customary traction control practices such as adjustments in timing, launch rpm, is very strictly prohibited. Jr. Pro Stock Tech director has full discretion to ascertain if the use of a traction control device has been implemented. Any person found in possession of a deemed illegal traction control device will be subject to immediately disqualification and forfeiture of any paid in entry fees.
A maximum of one pressurized container (excluding nitrous and fresh air systems) per vehicle is permitted. All pressurized bottles must meet D.O.T. 1800lb minimum speciﬁcation.
The use of tow vehicles is permitted.
Each crew member must have the proper starting line credentials and must were matching attire.
The driver when in the vehicle, from the ready line until the vehicle is safely stopped on the return road, is required to have all safety restraint systems (including the helmet) on and be securely fastened in the vehicle at all times
A Valid state or government issued driver’s license beyond a learner/s permit level is mandatory for cars running 10.00 or slower. A valid NHRA competition license is mandatory for cars running 9.99 or quicker, at a NHRA Member Track. A valid NHRA or an IHRA competition license is mandatory at an IHRA Member Track.
Note: It is ultimately the competitor’s responsibility to familiarize themselves with the PSCA class requirements as well as all NHRA safety requirements. The competitor agrees they bear the ultimate responsibility when it comes to safety and how it complies with the PSCA and NHRA rule books. The competitor also agrees that no one else other than the competitor is in the best position to know about how their particular race car has been constructed and how to safely operate.
Body style weight break table
Body Type Years
GM F Body 67-79
GM G Body 78-89
Chevy II / Nova 62-67
Dodge Valiant 59-62
Ford Maverick / Mercury Comet 70-77
Plymouth Barracuda 64-69
Body Type Years
Dodge E Body 70-74
GM A Body 68-77
Ford Mustang 64-73
Mercury Cougar 67-70
Chrysler A Body 63-76
Body Type Years
Chevrolet Bel Air 55-58
Ford Falcon / Mercury Comet 64-65
Chrysler B Body 66-75
GM B Body 58-76
GM A Body 64-67
Ford Fairlane 62-69
Ford Torino / Mercury Montego 68-74