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This is a Copy of the "DECO" Manual that was written in Pagemaker 4. Some spacing and punctuation may be inaccurate. Reference to pictures is not applicable. This may not be used in place of the "OFFICIAL" manual printed and distributed by QMA.

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QUARTER MIDGETS OF AMERICA (Q.M.A.)

ENGINE RULES and TECHNICAL MANUAL

for

DECO, CONTINENTAL

and

1/2 MIDGET

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I. BASIC ENGINE:

A. This technical manual applies only to the following engines and their component parts:

1. Continental models AU7R & 717.

2. Detroit Engines model # DE7R.

3. Deco Grand models DE2R & DE7R.

4. Other similar engines and components specifically approved by Q.M.A. as replacements for the preceding engines.

5. See Section VIII for 1/2 Midget engine specifications.

B. These engine rules are for use with the preceding engines when used in the Super Stock, Modified, "B" Modified and "AA" Modified classes.

C. All engines, except 1/2 Midget will be four (4) cycle, normally aspirated, air cooled and American made. Blocks will be cast iron or similar ferrous material. No overhead valves, fuel injection, blowers or free spinning flywheels. The gear box is not considered a part of these engines, there fore any gear box may be used.

D. All special (i.e. after market, of the same or different basic design) engines must be approved by Q.M.A.

E. All component parts, unless specifically excepted from technical inspection, are subject to technical inspection. All after market and special parts that are subject to technical inspection by these rules, may be required to be approved by Q.M.A.

F. Continental blocks may be machined so as to bring them to Deco block dimensions.

F. NO MODIFICATIONS, ALTERATIONS, ADDITIONS, SUBTRACTIONS,, DELETIONS, OR OTHER CHANGES ARE PERMITTED TO BE DONE TO THESE ENGINES OR THEIR COMPONENT PARTS UNLESS SPECIFICALLY ALLOWED IN THESE RULES.

II. MEASUREMENTS AND TOLERANCES

A. Unless otherwise stated all measurements will be made to plus or minus 1/2 of the least significant decimal place of each stated dimension. Dimensions given in fractional form are for reference only and will be converted to three place decimals for all technical measurements.

III. CLASS: NOVICE

A. WHEN THE ABOVE LISTED ENGINES ARE USED IN THE NOVICE CLASS ALL RULES AND SPECIFICATIONS FOR THE SUPER STOCK engine CLASS WILL APPLY. WHEN OTHER THAN THE ABOVE ENGINES ARE USED FOR NOVICE SEE THE APPROPRIATE ENGINE TECHNICAL MANUAL.

B. RESTRICTOR PLATE: NOVICE CARS USING THIS SERIES ENGINE MUST RUN A Q.M.A. APPROVED RESTRICTOR PLATE. THE PLATE IS TO BE INSTALLED BETWEEN THE CARBURETOR AND THE INTAKE MANIFOLD WITH A GASKET ON BOTH SIDES. EACH GASKET MUST HAVE A .065" MAXIMUM THICKNESS WITH A MINIMUM AIR FLOW HOLE DIAMETER OF .750". NO TAPERS OR OTHER AIRFLOW ALTERING METHODS MAY BE USED. ALL AIR ENTERING THE ENGINE MUST PASS THOROUGH THE RESTRICTOR PLATE CENTER HOLE. RESTRICTOR PLATE MUST BE AN UNALTERED Q.M.A. APPROVED PLATE. RESTRICTOR PLATE IS TO BE A MAXIMUM OF .063" THICK WITH A .375" DIAMETER AIR FLOW HOLE, TOLERANCE = +.000",-.003". RESTRICTOR PLATE MUST BE RUN AS RECEIVED, NO ALTERATIONS OF ANY KIND ARE ALLOWED. ANODIZING ON THE PLATE MAY NOT BE DISTURBED. IDENTIFICATION TAB IS TO BE VISIBLE AT ALL TIMES. INSPECTION OF PLATE MAY BE DONE AT ANYTIME. INSTRUCTIONS INCLUDED WITH THE RESTRICTOR PLATE MUST BE FOLLOWED.

IV. CLASS: SUPER STOCK

A. FUEL SPECIFICATION:

Gasoline, automotive type only. No racing, white or aviation gasoline. No additives.

B. Right rear wheel drive only.

C. ENGINES AND THEIR COMPONENT PARTS USED IN THIS CLASS MUST BE STOCK, AS MANUFACTURED. EXCEPTIONS ARE SPECIFICALLY LISTED IN THESE RULES. NO OTHER ALTERATIONS, MODIFICATIONS, ADDITIONS TO OR SUBTRACTIONS FROM ANY COMPONENT, PART OR SPECIFICATION WILL BE PERMITTED IN THIS CLASS.

D. ENGINE BORE and STROKE: Bore: 2.125" + .030" + .004" equals maximum bore of 2.159". Stroke: 2.00" + or - .015". Stroke minimum equals 1.985". Stroke maximum equals 2.015".

TECHNICAL INSPECTION SEQUENCE
Note: The items listed are in the normal order of engine inspection.

1. Carburetor

Carburetors approved for use on Super Stock engines are the Tillotson MT25A, Carter model N, No. 16, and the Walbro models LMG and LMB. Picture # 1 shows the areas of the Super Stock carburetors to be inspected. NO MODIFICATIONS TO THROTTLE SHAFT, BUTTERFLY OR AIR PASSAGEWAY. THEY MUST REMAIN STOCK. EXCEPT VENTURI MAY BE REAMED TO .506 MAXIMUM. The venturi must remain round. The jet tube may be shortened. The mixture screw and the needle and seat may be changed. Butterfly screws may be trimmed. Carburetor must remain stock appearing. No accelerator pumps, enlarged fuel bowls, or fuel pumps. Carburetor bowl drains may be removed and the hole plugged or welded. Walbro carburetors that had an original venturi size of less then 1/2" must be enlarged to .475" minimum to .506" maximum. The resulting longer straight area of the venturi must be left as reamed. There will be no machining or altering of the tapered area leading to or from the longer straight portion of the venturi that is the result of reaming the smaller venturi to a larger size. Other style numbers may be approved by National Technical Committee on request if they meet Q.M.A requirements. Any type external attachment to throttle shaft allowed. Any throttle support brackets may be used. No device that may be used to direct or channel air flow to the carburetor can be closer than 3" to the carburetor or to the carburetor air filter if used.

TECH PROCEDURE: Remove carburetor and check Venturi for .506" maximum and .475" minimum diameter. Check air passageway for alterations, none allowed. Check throttle shaft minimum diameter .210". Check butterfly, minimum thickness .024". See picture #1.

2. Air Cleaner

If used may be any type. Air cleaner adapter must not be over 1.375" in length, straight walled, flat bottomed and parallel with carburetor air passageway. Must be affixed to stock carburetor using existing air cleaner mount holes. If air cleaner is removed, the air cleaner adapter must also be removed.

TECH PROCEDURE: Check length and mounting holes.

3. Manifold

Stock or after market intake manifold P/NAA7-F-444 or AA7-FA-410 only.

TECH PROCEDURE: Check for alterations to the inside of the manifold, no grinding, polishing or coatings allowed. Some of the early after market aluminum manifolds had a ring ground just inside the flange of the manifold so they would fit on the jig for machining of the flange. This is acceptable. There are two after market manufacturers of intake manifolds. One of the companies is using shot balls, and the other is using glass beads to clean the manifold after casting. The shot tends to darken and smooth the aluminum. It is not a coating or performance enhancement, just a different process of production, either is acceptable.

4. Carburator and Manifold Gaskets

Any make of fiber manifold gasket with a maximum thickness of .063" (1/16) may be used. No slots, perforations, or alterations that would allow additional air into the engine. No loose bolts, warped flanges, etc. that allow additional air into the engine. All air and fuel entering the engine must pass through the carburator.

TECH PROCEDURE: Check gasket for maximum thickness. Check for any slots, perforations, loose bolts, warped flanges, or alterations that could allow additional air into the engine.

5. Head

Only stock unaltered cylinder heads part numbers AA7-A-504 and AA7-A-508 or Q.M.A approved after market heads may be used. All heads may have a 14mm Heli-coil or similar threaded insert installed to repair spark plug threads. Insert must be installed square to head and in original location. Heads may be bead blasted or wire brushed to clean carbon. No material may be removed from inside the combustion chamber area.

Stock heads may have no alterations except the following:

A. Some heads may be bent or warped on edges and need to be filed flat. This may only be done on the outside of the sealing bead, and the part numbers must not be removed. Head sealing bead may be lightly sanded, but must not be removed. The sealing bead ranges from .005" to .014" (reference only). The combustion chamber above valves should measure between .263" to .270" (reference only).

B. Head bolt holes on top side of head may be spot faced flat. No material may be removed from cooling fins. All holes in head must be in original location and not moved in any way whatsoever, such as tipped, moved over, up or down.

After market heads will be:

A. Made by a Q.M.A. approved manufacturer.

B. Used as manufactured, NO alterations allowed, except spark plug HeliCoil.

TECH PROCEDURE: Check for alterations inside of sealing bead area. Sealing bead and number must not be removed. No material removed from cooling fins. All holes in head must be in original location. See pictures #2, 3, & 4.

6. Head Gasket

Stock head gasket or gaskets of stock inside configuration made of copper, or aluminum may be used. Thickness .040" minimum to .066" maximum.

TECH PROCEDURE: Check .040" to .066" dimension around the outside of the sealing bead area on the gasket. Coating or gasket sealants may be used on gaskets. Recommend no fiber gasket, as thickness may not be legal after use.

7. Spark Plug

Any type automotive spark plug may be used.

8. Firing

Firing must not occur before the piston reaches .055" B.T.D.C. measured with flywheel “in”, i.e. sufficient hand pressure may be applied to the crankshaft to remove any static clearance with the gearbox bearing. No tools may be used to remove this clearance. Firing is to be checked with point cover in place, as run and without breaking the seals. Wire from coil to points must be cut if there is no other disconnect method. A male and female wire connector may be added to this wire. Only one wire is allowed from points to safety kill switch.

TECH PROCEDURE: To check firing depth mount a dial indicator on the block deck over the center of the piston and set it to "0" at T.D.C. Timing must be checked with point cover in place as run. It may be necessary for the technical inspector to cut the wire from the coil to the points so technical inspection of firing can be done without seals being broken. Disconnect wire from coil to points and connect a continuity checker to the wire that is connected to the points. Rotate flywheel counter clockwise until points close, approximately .100" to .150" before T.D.C. Next rotate flywheel clockwise slowly until the points open and continuity is lost. This is the firing point and the corresponding indicator reading must be .055" B.T.D.C. or less. A test light, buzzer, Ohmmeter or other similar device may be used as a continuity checker. If necessary use the one that shows the firing to be legal.

9. Points and Condenser

Any make of automotive type mechanical contact points may be used. Any make of automotive type condenser may be used. Only one set of points and one condenser may be used. Condenser must be mounted on the engine. Chip type condenser may not be used.

TECH PROCEDURE: After the firing has been checked remove the point cover and check for automotive type points and condenser. Be certain there is only one condenser. No chassis mounted condensers allowed.

10. Point Plate and Cover

Any style point plate and cover may be used if stock timing is maintained per rules. All clips, screws, holes, etc. in point plate and cover must be completely sealed so no adjustments can be made without breaking seals.

11. Point / Distributor Shaft

Stock or after market point / distributor shaft and lobe. Shaft diameter .375" + or - .005". Diameter of lobe, .740" minimum to .770" maximum and a minimum of .700" from flat to radius of lobe. Lobe must be stock shape. No offset lobes. Stock style or bolt on lobe is allowed. Bushing of the distributor shaft hole is allowed. Bushing must be installed in stock location. No roller or needle bearings of any type allowed.

TECH PROCEDURE: Check lobe and shaft dimensions. See picture # 5.

12. Stroke

Stroke 2.00" +/- .015". Minimum 1.985", maximum 2.015".

TECH PROCEDURE: Check with dial indicator mounted on deck of block over piston, set indicator to “0” at B.D.C. and rotate crankshaft until maximum reading is observed, continue rotating to confirm "0".

13. Bore

Bore maximum 2.159". Cylinder bore must remain in original stock location. No chroming or plating.

TECH PROCEDURE: Check bore with plug gages. If not available, use dial calipers or inside micrometers.

14. Piston Extension

Piston not over .020" above top of block deck at T.D.C.

TECH PROCEDURE: Check with indicator mounted on deck of block, set indicator at “0” setting on deck, swing over piston and turn crank to maximum extension of piston out of block. Other methods may be used. Carbon may be removed.

15. Shroud & backing plate

Any make or material may be used, but must remain stock appearing. Air inlet hole size is 5" +or- .250". Air deflector may be any material and must be stock appearing. Air deflector must be used.

TECH PROCEDURE: Visual. See picture # 6.

16. Cylinder and Head Baffles

Any make may be used. No head support plates.

17. Flywheel

Only Fairbanks Morse or Phelon flywheels may be used. Both manufacturer's flywheels may be balanced by drilling the back side of the flywheel rim only. This is the same procedure as used by both the manufacturers and must be followed. NO breaking of fins for balancing.

A. Fairbanks Morse: The three indentations on the flywheel may be drilled and tapped to allow the use of a puller. The backside of the flywheel may be machined to clear the stator. No machining anywhere else on the flywheel. Minimum weight is 28.0 oz. or 794 grams.

B. Phelon: Outside diameter of the flywheel may be cut for size and weight. Minimum outside diameter 5.750". The thickness of the flywheel may be turned to a minimum of 2.000". This dimension may only be achieved by cutting the outside face of the air fins. Minimum weight 29.0 oz. or 822 grams. On some Phelon flywheels, the inside radius below the magnets may have an area that wasn’t machined deep enough, and it drags on the coil. This radius may be machined to clear the coil. This area may only be machined back to the flat cast portion of the inside of the flywheel. The inside diameter of the flywheel may be cut to a maximum of 4.630" if necessary to eliminate an out of round condition on some later production flywheels. These are the only areas of the Phelon flywheel that can be machined.

TECH PROCEDURE: Check for machining in allowed areas only, and check weight. Check breakage of fins for balancing. See pictures # 7 & 8.

18. Stator

Stator plate bolt holes must not exceed .281", and plate must not be advanced in any way whatsoever. No mixing of stator, flywheel and coils of the Phelon and Fairbanks Morse systems.

TECH PROCEDURE: Check bolt holes for size. Check plate and coil mounts for any alterations. Check for mixing of components. No modifications. See pictures # 9 & 10.

19. Cam Lift Measured Off of Valve

Maximum lift on exhaust. 177", maximum lift on intake .202".

TECH PROCEDURE: Check with indicator mounted on valve head and all valve to tappet lash removed Check from lowest point on Cam lobe. Maximum only, no minimum.

20. Camshaft Lobe Centerline Specifications

The difference between camshaft lobe centerlines must be between 102.25 and 104.25 camshaft degrees when measured in the following manner.

TECH PROCEDURE: Method of measurement: Install a shim between each tappet and valve stem of sufficient thickness to remove all valve lash. Install dial indicators above valves and attach degree wheel to flywheel. Set pointer to approximate T.D.C. Rotate crankshaft in direction of normal running (clockwise) only. Observe readings according to the following procedure to determine centerline of lobes.

A. Set dial indicator to read "0" at highest point of valve lift (peak of lobe). Rotate crankshaft clockwise until valve begins to lift. Then take degree wheel readings before and after the peak at the technical inspector's choice of one of the following dimensions: .020", .030", .040", .050" or .060".

B. Add before peak and after peak degree readings together and divide by 2. This is the centerline of this lobe. Degree readings must always be in reference to T.D.C. on the degree wheel.

C. Repeat steps A and B for the other lobe.

D. Add intake and exhaust lobe centerline degree readings together and divide by two. This is the number of camshaft degrees between the lobe centerlines. This must be between 102.25 and 104.25 degrees. If it is, then the centerline is legal and no further tests are to be done. If not continue with step E.

E. Repeat A and B using 3 different readings of which 2 must be between 102.25 and 104.25 degrees.

If 2 are not then repeat steps A and B using all 5 readings of which 3 must be between 102.25 and 104.25 degrees. If 2 out of 3 does not pass and then 3 out of 5 does not pass then centerline is not legal.

EXAMPLE

Exhaust Lobe .020" before peak reading = 139.0 degrees B.T.D.C., .020" after peak reading = 72.0 degrees B.T.D.C. 139.0 + 72.0 = 211.0 divided by 2 = Exhaust centerline of 105.5 degrees B.T.D.C.

Intake Lobe .020" before peak reading = 80.0 Degrees A.T.D.C., .020" after peak reading = 124.0 degrees A.T.D.C. 80.0 + 124.0 = 204.0 divided by 2 = Intake centerline of 102.0 degrees A.T.D.C.

105.5 exhaust + 102.0 intake = 207.5 crankshaft degrees divided by 2 = 103.75 camshaft degrees.

Difference in cam lobe centerlines = 103.75 camshaft degrees.

21. Valve Springs

Any Type. No helper springs, only one spring per valve, no shims.

22. Valve Spring Seat

Valve spring seat may be spot faced.

23. Keeper & Retainer

Any retainers and keepers allowed.

24. Valve Guides

Valve guides may be installed providing they are .281" inside diameter + or - .005", no limitations on outside diameter. No tipping or offsetting of guides.

TECH PROCEDURE: Check for tipping or offsetting to increase lift.

25. Valves

Stock and after market valves may be used, and the following specifications must be met.

A. Intake Valve:

1. Minimum weight 26 grams.

2. Diameter of stem .281" +/- .005" and relieved area of stem .250" minimum by .750" long maximum, measured from under head at edge of 45 degree angle.

3. Diameter of head .922" maximum.

4. Valve face 45 degrees only.

5. Any keeper and retainer allowed.

6. The top of the valves will be flat (except for numbers) and the margin area will be straight with no detectable radius.

7. Valve head thickness .085" minimum, measured at edge of 45 degree angle to top of valve head.

8. Welding to valve stem (tappet end) allowed.

9. Some portion of the flat face of the valve (not including the raised numbers) must be above the deck surface of the block.

10. Valve may have small hole in center of head.

11. No swirl polishing of valves.

12. There will be no definitive angles between the 45 degree face and the stem of the valve.

B. Exhaust valve:

Same as the intake valve except the following:

1. Minimum weight of valve 25 grams.

2. Diameter of head .849" maximum.

TECH PROCEDURE: Check valves for weights and dimensions. See picture # 11.

26. Valve Seat

Valve seats may be installed or replaced if necessary. Inside diameter must remain stock, intake .825" maximum, exhaust .755" maximum. No limitation on outside diameter of valve seat. Must be installed flat with deck. Seats must not be installed backwards. 45 degree seat to be on block deck end of valve seat. Three angle seats permitted, but contact surface with valve must be 45 degree. No cutter and/or stone marks or cuts of any angle can be in excess of 1.000" in diameter on the valve seat or block deck.

TECH PROCEDURE: Check inside diameter of seat for maximum dimension of .825". Outside diameter of top cut is very hard to measure, use dial calipers.

27. Intake Port

Intake port at valve .825" maximum diameter to a depth of .625", measured from deck, down port wall to reamer edge, reamer edge angle must not exceed 60 degrees. Intake port at flange .825" maximum diameter to a maximum depth of 1.100", measured from flange down port wall to reamer edge, reamer edge must not exceed 60 degrees. No polishing or grinding. NOTE: This does not mean that the intake flange surface can be machined to allow more depth in port. A specification from the center head bolt to the intake flange of two inches (2.000") minimum will be used to determine true port depth to be allowed, with a .025" tolerance because of the variance in the head bolt location. A sleeve may be installed in intake port at flange for repairs, maximum length of .437", maximum inside diameter .825". Machining below sleeve cannot be any larger than .830". No machining or alteration by any method will be allowed to any area of the ports unless specifically allowed in this rule.

TECH PROCEDURE: Check port size with plug gages or dial calipers. Check machined depth with depth gages or dial calipers. On flange side of intake, if depth is questionable, use port fixture for measuring. Visually check ports for alteration, polishing, etching or grinding marks. See picture # 12.

28. Exhaust Port

Exhaust port diameter at valve maximum .755" to a depth of .625" , measured from deck down port wall to the reamer edge, angle of reamer edge must not exceed 60 degrees. Some blocks are factory machined larger under the exhaust seat, this is acceptable.

Exhaust port diameter at flange maximum .763". No polishing or grinding. A sleeve with a maximum inside diameter of .763" by a maximum .625" length may be installed in exhaust port on flange side.

When machining for sleeve or for opening exhaust port on flange side to .763" diameter, machining can be no deeper than the flange side of the valve guide outside diameter.

If port is sleeved maximum diameter of machining under sleeve is to be no larger than .875" and no deeper than flange side of valve guide outside diameter.

Machining, as well as sleeve, to be straight walled, with no tapers. Both ends of sleeve must be square cut, with no angles to improve air flow. No machining or alteration by any method will be allowed to any area of the ports unless specifically allowed in this rule.

TECH PROCEDURE: Check port size with plug gages or dial calipers. Visually check ports for alteration, polishing, etching or grinding marks.

29. Piston

Unaltered stock piston part number AA7-A-407 or after market piston may be used. Piston is not to be cam ground. After market piston material will be aluminum only with no special coatings. Minimum weight will be no less than 99 grams. Stock ring size and location is to stay the same. Piston must have a flat top. No bump or raised areas, but may have a centering hole for machining purposes. Stock wrist pin diameter and location must be maintained, steel pin with buttons may be used. The following piston dimensions will be used:

A: Top of piston to the top edge of the first compression ring will be .190" + or -.035".

B. Top of the piston to the top edge of the wrist pin bore will be .900" +.020" - .035".

C. Overall piston length from top of piston to the bottom edge of the piston skirt, 2.000" + .010", -.045"

D. Piston pin centerline must intersect piston centerline. Maximum offset + or - .005".

E. Piston pin and button weight 18 grams minimum.

F. Piston skirt taper, maximum .002" per side, .004" total.

G. Wrist pin diameter .419".

TECH PROCEDURE: Check weights and dimensions with dial calipers and scales. Piston skirt taper maximum .002 per side. See picture # 13.

30. Rings

Only one piece rings of stock size and shape allowed. No chrome, chrome faced or gapless rings allowed.

TECH PROCEDURE: Visual

31. Rod

Any connecting rod with a minimum weight of 90 grams including inserts, bolts and dipper. No needle bearings allowed on either end of rod. Any oil dipper allowed.

TECH PROCEDURE: Weigh rod with gram scale.

32. Rod Inserts

Any type of rod insert may be used. No needle bearings. Sizes; Standard, .002",.010",.020".

33. Crankshaft

Stock crankshaft or Q.M.A approved after market replacement crankshaft. The AA7-C-426 crankshaft may have spline added and be brought up to specifications of stock crankshaft. Stock crankshaft with removable gear allowed. Crankshaft journal may be turned or built up to obtain the standard or under size desired. Standard is .8745/.875", under sizes are .002/.010/.020". Gear box splines may be replaced. Unsplined stock crankshaft is allowed. Crankshaft may be cleaned up to permit gearbox bearing to be a sliding or loose fit on reduction gear side only. Crankshaft may have nitrided finish. Crankshaft is not to be altered in any other way. Crankshaft end play, no maximum amount, shims allowed on either or both ends of crankshaft. Crankshaft flywheel keyway must be in stock location and key must be used to locate flywheel.

TECH PROCEDURE: Visually check for grinding or polishing on crank counter balances. Check for additional drilling of counter balances. See picture # 14.

34. Camshaft

Stock or after market.

Measurements:

Heel to Peak - Exhaust .988" maximum - .975" minimum Intake 1.013" maximum - 1.000" minimum. Heel to Heel - Exhaust .811” minimum .821" maximum Intake .811" minimum .821" maximum. Difference or total lift: exhaust .177" maximum Intake .202" maximum. Maximum lift on exhaust .177", maximum lift on intake .202". Base circle maximum .007" out of round. Heel to heel minimum .811" maximum .821". A new gear may be installed. Camshaft must be a one piece and of conventional design other than press on gear. Cam and gear must be made of ferrous metal. Lobes must fit through Q.M.A. templet. Cam pin hole may be drilled to a larger size. An additional cam pin may be used.

35. Valve and Tappet Guides

New guides may be installed, provided they are .281" + or - .005" inside diameter. Any outside diameter is allowed. No tipping or offsetting of the guides.

36. Tappets

Tappet with stem diameter of .281" + or - .005". Must have flat base surface, maximum wear .002". Head diameter .731 “ to .753". Any overall length. Head thickness, minimum .070”. Tappet must be made of steel, no coatings. Tappets may be polished. No tipping or offsetting of tappets to increase leverage or valve lift.

37. Deck Height

Measured from block deck to the center of point/distributor shaft, 4.610" minimum, 4.670" maximum.

TECH PROCEDURE: Measure from block deck to point/distributor shaft, with depth micrometer thorough valve guide and tappet guide. Add 1/2 of diameter of point/distributor shaft to micrometer measurement to obtain deck height.

38. Oil Pan

Any stock or after market pan allowed. Must be of stock size and shape. Pan may be drilled and plugged to allow checking of oil. Pedestals may be removed. Stock splash pan mounted on pedestals is the only device allowed in the oil pan or crankcase. Stock splash pan may have holes added, subtracted, or changed in size. Basic shape must stay the same.

TECH PROCEDURE: Visual

39. Crankshaft Bushing

Bushing on the flywheel side must remain stock appearing. Any flange thickness allowed. Must be bronze or brass only. No needle bearings.

TECH PROCEDURE: Visual

40. Block

Machining is allowed so as to bring Continental blocks to Deco block dimensions. Block may be externally strapped and broken block may be brazed or welded. No welding, brazing or other repairs may be done in ports or combustion area. Breather may be added, but no alternations of block allowed, except block may be drilled to hold breather baffle. Boss on block may be removed to receive gearbox. Welding inside block is okay, but must not alter any original dimension or location of holes. Except as allowed above any block altered or repaired in any way that causes the original dimensions to be changed is illegal for the stock class. Painting or chroming outside of block only.

TECH PROCEDURE: Visually check block for any alterations that change the original dimensions. Check for any coating or painting of inside of block. See picture # 15.

41. Sleeves

Cast iron cylinder sleeve may be installed. Must be installed so that it is centered on the original bore centerline. Must not be offset in block in any way whatsoever, such as tipped, moved over, up or down.

TECH PROCEDURE: Visually check.

42. Miscellaneous

Any kind of nuts, bolts, studs or washers are allowed and may be safety wired. Stripped out threads may have Heli-coil or similar threaded inserts installed provided the original hole location and the same thread size is retained. Gear Box is not considered a part of the engine, therefore any type gear reduction may be used. No painting, plating, coating or chroming to the inside of engine block or intake manifold.

V. CLASS: MODIFIED

A. FUEL SPECIFICATION: Same as Super Stock class.

B. Right rear wheel drive only.

C. ENGINE: Same as Super Stock. Bore 2.159" maximum. Stroke 2.000" + or - .015".

D. All modifications allowed in this class except for the following:

1. Block

A. Broken blocks may be repaired by welding, brazing or strapping. No welding, brazing or other repairs may be done in ports or combustion area.

B. Cylinder sleeves may be of any material. Cylinder bore must be centered on and parallel to the original cylinder bore center line.

C. Intake and exhaust valve center line must remain parallel to the original valve center line.

D. Tappet center line must remain parallel to the original tappet center line.

E. Combustion chamber surfaces must remain the same as Super Stock.

2. Camshaft

Cam and cam technical procedures are the same as Super Stock. Cam pin hole may be drilled to a larger size. An additional cam pin may be used.

3. Deck Height

Same as super stock.

4. Flywheel

Any type of flywheel may be used, maximum 32 ounces or 907 grams, minimum 27 ounces or 765 grams. Balancing is OK. Multi-piece flywheels must function the same as a one piece flywheel.

5. Valve Seats

Same as Super Stock. Except any seat angle may be used.

6. Cylinder Head

Same as Super Stock.

7. Head Gasket

Same as Super Stock.

8. Piston

Any flat top piston is allowed. No part of piston may protrude more than .020" above block deck at top dead center (carbon may be removed).

9. Exhaust Port

Exhaust port at valve maximum .755 to a depth of .625, measured from deck down port wall to the reamer edge. Reamer edge angle must not exceed 60 degrees. Some blocks are factory machined larger under the exhaust seat, this is acceptable. Exhaust port at flange maximum .875" no polishing, grinding or relocating. A sleeve with a maximum inside diameter of .875" by a maximum .625" length may be installed in exhaust port on flange side. When machining for sleeve or for opening exhaust port on flange side to .875" diameter, machining can be no deeper than the flange side of the valve guide outside diameter. If port is sleeved maximum outside diameter of machining under sleeve is .900" and no deeper than flange side of valve guide outside diameter. Machining, as well as sleeve, to be straight walled, with no tapers. Both ends of sleeve must be square cut, with no angles to improve air flow. No machining or alteration by any method will be allowed to any area of the ports unless specifically allowed in this rule.

TECH PROCEDURE: Check port size with plug gages or dial calipers. Visually check ports for polishing or grinding marks.

10. Intake Port

Same as Super Stock.

11. Tappets and Tappet Guides

Any flat based tappets may be used. Maximum allowance for wear is .002". Any size tappet guides may be used. They must be installed so that the center line of the valve guide bore is parallel to the center line of the corresponding tappet guide bore and intersect the centerline of the point / distributor shaft bore.

12. Valves and Valve Guides

Any valves may be used. Maximum head diameter, intake .925", exhaust .852". The edge of the valves must be above the surface of the deck. All other modifications to valves allowed. Any size valve guides may be used. They must be installed so that the center line of the valve guide bore is parallel to the center line of the corresponding tappet guide bore.

VI. CLASS: “B” MODIFIED

A. FUEL SPECIFICATION: Same as Super Stock.

B. DRIVE WHEEL: Two wheel rear drive optional.

C. ENGINE: Bore 2.125" + .060" + .004" or 2.189" maximum Stroke 2.000" +/- .015".

D. All modifications allowed in this class except the following:

1 Camshaft Same as Super Stock.

2. Flywheel Same as Modified.

3. Tappet and Tappet Guides Same as Modified.

VII. CLASS: “AA”

A. FUEL SPECIFICATION: Gasoline is the same as Super Stock or straight methanol, no additives.

B. DRIVE: Two wheel rear drive optional.

C. ENGINE: Bore 2.250" + .050" + .004" clean up, 2.304" maximum. Stroke 2.000" plus or minus .015". No overhead valves. Must be air cooled.

D. All other engine modifications allowed in this class.

VIII. CLASS: 1/2 MIDGET

A. FUEL: Same as "AA"

B. ENGINE RULES:

Any make 4 cycle engine, American or foreign made. 253 cubic centimeters or 15.439 cubic inches maximum displacement. No blowers, no fuel injection. All other modifications allowed.

To calculate displacement use the formula (Bore divided by 2) squared x 3.1416 x stroke = displacement. (Example: If bore = 2.659" and the stroke = 2.000", then 2.659 divided by 2 = 1.3295, squared = 1.76757025 x 3.1416 x 2.000 = 11.105997 cubic inches.)

End of cdmrev97