Non Wing 305 SPRINT CAR RULES
Updated by Riverside 9/2/2009
General Engine Rules
316 max cubic inch limit/ 3.48 max stroke
All engine components must be of ferrous material only. No titanium or ceramics.
Water Pumps: May be cast iron or aluminum, stock OEM style, must bolt in the stock location.
15.1 Engine Block
15.1.1 OEM production cast iron 305 Chevrolet only (no aftermarket). Ford 302??
15.1.2 No repositioning, boring, or bushing of cam or lifter bores.
15.2 Crankshaft
15.2.1 OEM production crank or ANY brand of 3.480 stroke w/stock weight. (balancing only no “knifing”)
15.3 Connecting Rods
15.3.1 Any OEM or aftermarket stock length (5.7”Chevrolet “I” beam rod. ) No billet allowed.
15.4 Pistons
15.4.1 Any flat top two or four valve relief allowed.
15.4.2 Max “0” deck height (Piston may not protrude above deck surface)
15.4.3 Any piston rings.
15.5 Valve Train Specs
15.5.1 Timing sets - Chain only. No belt or gear drives allowed.
15.5.2 Valve springs straight wound only max seat pressure 120lbs. Must have 5 full coils.
15.5.3 Any flat tappet lifter with max diameter of .842 for Chevy & .875 for Ford. NO roller or mushroom style lifters allowed.
15.5.4 Any 5/16 diameter pushrod.
15.5.5 Any steel 7 or 10 degree valve spring retainer allowed.
15.5.6 Stamped steel or roller rocker arms allowed. No shaft systems, rev kits, stud girdles, or valve stabilizers allowed.
15.6 Oiling System. Wet Sump Only (No Dry Sump allowed).
15.7 Camshaft
15.7.1 Flat Tappet only/No Rollers. No “hard face” cams.
15.7.2 Chevy's must utilize stock firing order (18436572)
15.8 Valves:
15.8.1 2.02 intake/1.60 max head diameter allowed.
15.8.2 11/32 valve stem diameter only. NO titanium valves.
15.9 Cylinder heads:
15.9.1 Cast Iron only, no modifications allowed to the port, bowl, or chamber area. Minimum chamber volume
is 64cc for Chevrolet and 58cc for Ford engines. The only stock VORTEC head allowed is the 350 Vortec.
Any GM stock head with minimum 64cc chamber is allowed. No grinding, polishing, welding, acid or caustic work, shot peening, glass beading, coating, or other process that will alter the machined surfaces or natural sand cast finish. Heads must be untouched. Comparisons will be made to known legal heads if questions arise. The only exception allowed to this rule will be when media blasting has been used for cleaning purposes only. This determination will be made by the tech inspector(s). Any questionable parts may be presented to track management for inspection prior to assembly to avoid possible issues later.
15.10 Approved cylinder head castings:
15.10.1 Small Block Chevy:
15.10.1.1 RHS Pro Action p/n 12319. (200 runner, 2.02 / 1.60 valves, 64 cc chamber, straight plug)
15.10.1.2 RHS Pro Action p/n 12320. (200 runner, 2.02 / 1.60 valves, 64 cc chamber, angle plug). --Part number 223400000 or 223400000A stamped in the accessory bolt mounting flange on one end of the head, also has 200 in casting under valve cover.
15.10.1.3 Dart Iron Eagle p/n 10320010 or 10230010P. (200 runner, 2.02 / 1.60 valves, 64 cc chamber, straight plug) --Part number stamped in the accessory bolt mounting flange on one end of head, also has 200 in casting under valve cover.
15.10.1.4 Dart Iron Eagle p/n 10310010 or 10310010P. (200 runner, 2.02 / 1.60 valves, 64 cc chamber, angle plug). --Part number stamped in the accessory bolt mounting flange on one end of head, also has 200 in casting under valve cover.
15.10.1.5 World Products Motown p/n 011250. (200 runner, 2.02 / 1.60 valves, 64 cc chamber, straight plug). -- Part number in casting under valve cover.
15.10.1.6 World Products Motown p/n 011150. (200 runner, 2.02 / 1.60 valves, 64 cc chamber, angle plug). –Part number in casting under valve cover.
15.11 Fuel System
15.11.1 Injectors or carburetor allowed
15.11.2 Cam drive fuel pump only
Tires/Weight
16.1 Tire must durometer 38 minimum at any time.
16.2 Must weigh 1400 pounds.
XX Gear Rule
-All cars will run the same final drive ratio of 6:68 or less. All cars will be required to have a minimum ¼” inspection hole drilled in the driveline tube positioned in such a manner to allow verification of above mentioned final drive ratio. This will allow the cars to turn in the 6,500 to 6,800 RPM range which should then make it unnecessary for the racer to “overbuild” the engine. Any violation of engine rules will result in disqualification of the car and driver for the remainder of the year. Cars must be affixed with a safety strap on drag link.
The halo bars on the 305’s are optional.