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Pro Gas Rules

CB Performance 044 Pro Gas Race Class

Body and Chassis Rules


Must be factory VW STEEL complete floor pan, stamped steel floor pans are mandatory and must be welded to tunnel. Pan head must be in place. Pie cutting of pan head is allowed for added caster.

Tubular chassis are NOT allowed

Narrowing of torsion Housing is allowed

Raising of torsion housing is allowed, Max-3 inches

Must retain factory frame horns, Frame horns may not be modified in any way

1 inch transmission raise is allowed for all cars, including raised torsion housing cars

9.0 inch maximum measured tire width

Wheelie bars may be used, 60” inch maximum length

NHRA engine oil containment pans or blankets must be used.

Roll bar or roll cage is mandatory and must be NHRA approved.


Type-1 and type-3 are allowed bodies for class.

Karman Ghia Body is allowed

Convertibles are NOT allowed

Factory windshield angle must be preserved

No open air vehicles allowed, I.E manx type vehicles, etc

Max 4” chop top allowed

Minimum roof height-48 inches

NO Sectioning of body allowed.

NO Channeling of body allowed

Fiberglass fenders, doors and front ends are allowed, no carbon fiber

Stock width fenders or wider mandatory

Rear fenders can be raised for tire clearance

Lexan windows are allowed

Deck lid is mandatory, Stock replacement fiberglass deck lids may be used, aluminum fabricated deck lids are allowed.


Dragster style wings are NOT allowed in this class. A wing of a single plane design is permitted. It must be mounted below the lowest point of the rear window and not more than 42” wide. Maximum height to be no more than 4” from it’s mounting point. Maximum gap between body and spoiler 1”. Wings/spoilers are allowed a max of two 48 square inch openings on top of the wing/spoiler. No air ducting above or below the openings is allowed. Air flaps on the back of the engine cover is allowed.

Deck Lids

Stock deck lids will be allowed a maximum of 6 inches lay back/stand off from the factory position. Deck lids are not allowed to be any higher than the lowest part of the rear window. Deck lids must be securely latched at bottom.

Air Induction

Non factory air induction, I.E. Naca Ducts, ducted air through scoops, under vehicle chassis,windshields is not allowed. For cars with non factory engine covers, follow wing/spoiler rules for allowable air vents. Cars that have air induction from racing in another class must show sufficient proof that air induction is disabled or car will not be allowed to race in class. If vehicle owner is caught modifying air induction before or after a round, vehicle owner and car will be disqualified and loss of payout and points will be implemented.

Pressure boxes and OR Carb trays are NOT allowed


Single knob adjustable rear and front shock may be used, must be commercially available

Aftermarket torsion bars and spring plates are allowed, must be commercially available.

Spring plates must be factory length.

NO electronic or pneumatic shock controllers are allowed

Narrowed axles are allowed

IRS suspension is allowed

Shifter and Clutch

H-Pattern shifter is the only shifter allowed

NO Vertigate style shifters allowed

NO electronic type shifter allowed

Allowable Clutch engagement is by cable or hydraulic, I.E Neal/CNC pedal assembly

Clutch release has to be foot operated only, NO air activated, solenoid activated clutch release allowed

Hydraulic or manually activated clutch management is allowed.


Allowed transmission- Type-1, Type-2, Mendeola

NO Sequential shifted type transmissions allowed

IRS to Swing axle conversion “Dave Folts” kits are allowed

Swing axle or IRS suspension only

NO coil over/ladder bar type suspension allowed

Weight Limit

Minimum Weight limit for CB 044 Pro Gas is set at 1725 lbs . There will be a 25 lb weight penalty for raised torsion housings. The weight penalty rule for CB 044 Pro Gas is subject to change if PRA deems necessary.

Engine Rules

2332cc Max Engine Displacement

84mm stroke max, Any manufacturer, may be flanged, wedge-mated, any main bearing dimensions O.K, min 2" rod journals, crank may be turned for repair, No offset grinding, No knife edging of crank is allowed.

Rods - Steel rods only, any manufacturer allowed, minimum rod length is 5.325, maximum rod length is 5.700, .866 I.D pin bushing only.

Push rods - Steel only, any manufacturer allowed

94mm bore max

Flat top piston only any manufacturer, any ring type allowed, 3 ring grooves Mandatory, No gas porting allowed, Minimum compression height-1.300, Minimum piston weight with pin- 475 grams, Valve relief’s are allowed.

Wrist Pins - Minimum wrist pin wall thickness-.120, Steel wrist pins only, .866 wrist pin diameter only.

044 CNC Wedge Port head as SPEC head for class. Heads must use components that are sold with the #1411 Wedge Port head, NO exceptions. Springs may be shimmed for proper installed height. Installed valve spring height must remain within 1.500-1.530, NO exceptions. Any depth flycut allowed, welding between chambers allowed for strength when heads are flycut. Welding of head in any other areas other than between combustion chambers is Not allowed. NO modifying, porting or blending of ports is allowed, NO modifying, un-shrouding, or blending of chambers is allowed. If seats are replaced to repair heads, intake seat I.D must remain at 1.530, exhaust seat I.D must remain at 1.320. Valve seat depth must remain at factory height if seats are replaced. NO shortening or profiling of valve guides is allowed. Intake manifold stud location may NOT be relocated.

Servicing of heads - If heads are serviced, all parts must be factory CB #1411 Wedge Port replacement parts, NO exceptions.

Rev Control - NO Internal or External rev kits allowed to control valve train.

Intake manifold - Accepted manifolds; CB Performance- IDA#3155 / IDF#3157, JAYCEE #S-8 ALLOWED STARTING IN 2016, Berg- IDF#GB580A / IDA#GB590 Scat- IDA#30122 IDF#30076 Manifolds may be welded up to 1-1/2 inches from base ONLY to allow match porting and strength, Manifolds may be match ported. Epoxy of any Kind is not allowed internally or externally on manifolds.

Valve and seat angles - Seat-30/45/60/75 degrees only. Valve-30/45 degrees only.

Rocker arms - max 1.5 ratio, any manufacturer, keep in mind that the valve springs are only capable of .630 lift.

Valve Springs - Valve springs may NOT be modified in any way. Replacement valve springs must be CB part# VW650

Cam - must be flat tappet cast iron cam any manufacturer is allowed

Cam gear - any manufacturer

Ignition - any type of distributor allowed, CRANK TRIGGER IGNITION IS ALLOWED STARTING IN 2016, PROGRAMMABLE CRANK TRIGGER CDI IGNITION BOXES ARE NOT ALLOWED. any manufacturers coil allowed, Locked timing or mechanical advance only, No timing control.

Case - stock magnesium or Auto Linea aluminum

Oil pump - Full flow style only, no dry sumps, external oil bypass allowed

Oil sump - any manufacturer allowed

Exhaust - any manufacturer allowed and any size allowed, step headers are allowed. NO over the top exhaust are allowed.

Carburetion - 48mm throttle plates max, 44mm venturi max, No Mechanical Injection allowed, No EFI allowed, Approved carburetors for class- Spanish or Italian Weber 48 IDA/IDF, Dellorto 48 DRLA, No carb modifications allowed to improve air flow, Aftermarket velocity stacks O.K, float bowl enlarging O.K

Lifters - cast iron only, no composite lifters allowed, must be standard VW O.D dimensions, Minimum lifter weight is 70 grams

Clutch - Stock style and J&G clutches and RLR Rev-6 are the only clutches allowed.

R6PG2016 -Rev-6 Clutch rule amendment starting in 2016

The Pro Gas Rev-6 clutch is not to be modified in shape; size, weight and or any other way except for maintenance due to wear from the disc, any repairs other than maintenance must be approved by CB Performance and/or RLR.

The units are to remain 6.250", single clutch disc, and no modifications to the clutch disc other than truing (grinding) for maintenance purposed are allowed.

The clutch units are serialized and numbered for identification purposed and must have the appropriate Pro-Gas designation to be used in competition.

Any units previously purchased and meeting the criteria described above and needing the Pro-Gas designation applied to their Rev-6 clutch can have that done at no cost by RLR.

Clutch Disc - Single disc ONLY, any diameter allowed, any manufacturer allowed. For the RLR Rev-6, the clutch disc must be the spec disc for Pro Gas, no other clutch disc is allowed when using the RLR Rev-6 clutch.

Flywheel - Must use steel flywheel, 12 lbs. min weight, 17 lbs Max flywheel weight, Flanged flywheels O.K

Fuel - VP C-12 will be the spec fuel for the class

Vacuum pumps are NOT allowed

Nitrous Oxide is NOT allowed

Data Acquisition - Data acquisition of any kind is NOT allowed. Competitors will need to remove oxygen sensors from exhaust systems before qualifying and elimination rounds begin. Competitors using data log computers, Race pack, etc will have to remove SD memory cards from the computer before qualifying and elimination rounds begin. If the data log computer does not use an SD memory card, competitor will need to show proof that the data log computer is disabled prior to qualifying/elimination rounds.