351= SLEEPER. FORD'S ORIGINAL 351 was the Windsor, closely related. by Denis Hill

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FORD'S ORIGINAL 351 was the Windsor, closely related to the 289-302's which powered many successful race cars in far flung forms of competition.

1 FORD'S ORIGINAL 351 was the Windsor, closely related to the 's which powered many successful race cars in far flung forms of competition. The 351W simply had a stroke 1/2-inch longer than the 302 and a new kind of free-flowing, big-valve head. Introduced in 1969 and replaced by the 351 Cleveland in 1970, the 351W never took the racing world by storm. Now the 351C is a new baby that is having some teething problems but shows great potential as a racing powerplant. In an effort to clear up some misconceptions about this engine and hopefully to establish a solid foundation from which racers can develop it, we herewith present a few facts, figures, and part numbers. This advice is based on research done by the factory so it should provide a good jumping off place. The 335 series engines were introduced in the 1970 model year. The factory used up the old 351 Windsor engines as 2-bbl. engines while the supply lasted. Meanwhile the 351 Cleveland came out as a 4-bbl. and later a 2-bbl. In '71 the 400, CJ, and Boss versions of the Cleveland engine were introduced. Then in '72 the Boss was renamed the 351 H.O. Identifying 335 series engines is not difficult. If the original engine is in the body with which it left the factory, one simply scopes out the identification tag in the driver's corner of the dashboard. The first digit represents the model year and the fifth digit (a letter) tells which engine you have. In descending order of desirability these are: (R) Boss or H.O., (Q) ' C.J., (M) ' V, (H) ' V, (S) ' V. Another identification tag is located under the coil and the number is also on the front of the block. If you're asking why the 400-inch version of the Cleveland rates so low in our ranking it is because this stroker engine has different rod journals from the 351 C, which limits interchangeability of parts. It, being a 2-bbl. motor, is also blessed with two-bolt main caps. You might note that the main and rod journals of the 400C match up with the 351 W, so there's room for some expermentation there if you have an old 351W block handy. To get the most racing engine for the least trouble, start with the 351 Boss or the 351 H.O. The Boss engine was introduced in the '71 cars and was superseded by the H.O. in '72. These are identical except for compression by Denis Hill 351= SLEEPER Canted valves, big ports, and a strong bottom end add up to a lot of yet unfulfilled potential for ^Ford's 351 Cleveland.

ratio and combustion chamber configuration. The differences are not as great as one might think. The '71 351 C.J., 72 351 C.J., and '72 351 4V are all the same.

2 ratio and combustion chamber configuration. The differences are not as great as one might think. The ' C.J., C.J., and ' V are all the same. These are good engines with the four-bolt mains but they don't have all the good parts of the Boss and H.O. Still, if you plan a complete rebuild, they'll do just as well. A warning is in order on these 4V engines: the '70 and '71 versions don't have the four-bolt mains. All the 2-bbl. engines have smaller valves and ports than their more heavily carbureted kin, and only the Boss and H.O. come with provision for valve lash adjustment, as the other engines all use hydraulic cams. One of the design features that makes the Cleveland so attractive as a racing engine is the canted valve configuration. The valves are canted at a compound angle to their respective heads for improved flow. In the 4V, Boss, C.J., and H.O. these valves are 2.19" for the intake, and 1.71" for the exhaust. The 4V and C.J. valves are designed for a multi-groove keeper which promotes rotation. The single-groove keeper used in the Boss and H.O. engines gives better control and should be used in high-rpm applications. The stem diameter of these Boss valves is 11/32". The ports of the Boss, C.J., and 4V are large and oval, BELOW- The Boss 351 gets a selected for hardness cast crank, but an aftermarket steel unit is recommended for sustained high-rpm applications. t. /. ABOVE- The harmonic balancer on the left is the one that comes with the ordinary 351C. The balancer at right is the heavier and more clearly marked "Boss" model. RIGHT-Boss 351 rod assembly is magnafluxed and used large, highstrength bolts and comes with better bearings than the ordinary 351 gets. LEFT The "Boss" and other highperformance versions of the 351 C get the four-bolt main cap while 2 bbl. engines do not. The timing chain housing incorporated in the front of the Cleveland block eliminates the need to route water through the intake manifold. DECEMBER resembling the Boss 302 heads. When properly ported and polished these heads will flow 450 cfm on the intake side and 300 cfm exhaust. The Boss and H.O. use selected connecting rods machined from SAE 1041 steel. These are shot-peened and magnafluxed and come with 180,000 psi, %" bolts. The whole deal is good for 7,500 rpm. The question of heads for a 351C engine gets complicated. Only the H.O. and Boss heads come set up for the adjustable rockers by means of which valve lash is attained. However, only minor machine work is needed to 49

One of the first and perhaps biggest decisions to attack in building a racing 351 is choice of heads. Are open chamber heads preferable to quench heads?

3 One of the first and perhaps biggest decisions to attack in building a racing 351 is choice of heads. Are open chamber heads preferable to quench heads? 351 = Sleeper BELOW-The quench Boss heads feature the same big valves as other 4 bbl. engines. The ports are larger than the older head. The '71 CJ and '72 H.O. heads feature open chambers, but are otherwise identical to the '71 Boss head. make the conversion (see "351 Head Job," Oct. '72 SCR). The '71 4V and Boss use the quench combustion chamber, while the '71 C.J. and all '72 engines use open chamber heads. The '71 4V has a cast aluminum flat top piston for a compression ratio of 10.7:1. The '71 Boss uses a forged aluminum pop-up piston to achieve a c/r of 11.1:1. The 72 C.J. gets a 9.0:1 out of a flat-top, and the '72 H.O. pulls a big 9.2:1 from a flat top forged piston. In short, the Boss is the only combination (quench head and pop-up piston) approaching performance. The mechanical cam 351 's use hardened & ground push rods with Boss 302 guide plates. The crank in these engines is cast iron, selected for hardness, 90% nodularity. The harmonic damper and flywheel are also stronger and heavier on the Boss and H.O. PART SELECTION One of the first and perhaps biggest decisions to attack in building a racing 351 is choice of heads. Are open chamber heads preferable to quench heads? First it should be noted that the current popularity of openchamber heads in automobile manufacturing is due to their ability to produce fewer pollutants. Open chambers also promote better breathing and good top end power. Quench heads help create a swirling of the air/fuel mixture and give better torque. Tests of otherwise identical engines have shown that the power-producing ability of open-chamber heads may be a couple of horses better than quench heads. This may not apply to every engine, and we don't know if it applies to the 351, but bear it in mind. On the subject of heads, you may run across a few oddball heads with 2.3" intake valves. Some of these were produced in 1970 but they hurt in the torque department. 50 STOCK CAR RACING

Part Number Stock 351 Boss Parts Description D1ZZ-6009-D Engine Short Block-71 D1ZZ-6010-D Engine Block-71 Boss-4-bolt selected hardness caps D1ZZ-6049-B Cylinder Head-71 D1ZZ-6051-C Gasket-Cyl.

4 Part Number Stock 351 Boss Parts Description D1ZZ-6009-D Engine Short Block-71 D1ZZ-6010-D Engine Block-71 Boss-4-bolt selected hardness caps D1ZZ-6049-B Cylinder Head-71 D1ZZ-6051-C Gasket-Cyl. Head-71 D1ZZ-6108-A Piston & Pin Assembly-71 std. red size D1ZZ-6108-B Piston & Pin Assembly-71 std. blue size C9ZZ-6135-E Piston Pin D1ZZ-6200-A Connecting Rod D1ZZ-6211-A Bearing-Con Rod (std. size) D1ZZ-6212-A Nut-Con Rod %"-24 D1ZZ-6214-A Bolt-Con Rod D1ZZ-6250-B Camshaft-Mechanical 71 D1ZZ-6303-A Crankshaft D1ZZ-6316-B Damper-Crank DOAZ-6345-B Main Cap Bolts V2"-13 x 3'A" C9AZ-6345-A Main Cap Bolts %" S Washer-Flat %" D1ZZ-6375-B Flywheel & Ring Gear D1ZZ-6500-B Tappets - Mechanical DOZZ-6505-A Exhaust Valve 1.71" dia. 5.05" long DOZZ-6507-A Intake Valve 2.19" dia. 5.23" long DOZZ-6513-A Valve Spring (#4 dark blue stripes) C9ZZ-6514-A Retainer C9ZZ-6518-A Keeper C9ZZ-6A527-A Stud-Rocker Arm 7/i6"-20 (top) 7/i6"-14 (bottom) C9ZZ-6A528-A Seat-Rocker Arm Fulcrum 71 C9ZZ-6A529-B Nut-Rocker Stud C9ZZ-6A536-A Seat-Valve Spring (before ) DOOZ-6A536-A Seat-Valve Spring (after ) C9ZZ-6A564-A Guide Plate-Push Rod DOOZ-6565-F Push Rod-Hardened 8.52" long (71) C9ZZ-6571-A Seal-Valve Stem 71 C9ZZ-6582-C Rocker Covers-Aluminum (R.H. & L.H.) Part Number D3ZZ-6051-A D1ZX-6500-CA DOZX-6505-A DOZX-6507-A DOZX-6A511-A... DOZX-6A585-A... D2ZX-6670-A DOAZ-9433-A D1ZX-9425-FA D1ZZ-9424-G 351 Boss "Competition Only" Parts Description.Gasket-Cyl. Head.Mechanical Tappets radius (to service above kit).exhaust Valve Lightweight (95 gms.) 1.71 "dia..intake Valve Titanium (85 gms.) 2.19" dia..valve Spring Three Piece (Load-130 Bearing Rocker Arm Kit Includes: bearing assy, bearing housing, nut, shaft and set screw.spring Oil Pump (increase pressure to 100psi).Gasket Kit-Int. Manifold (trim sides of steel gaskets) 351C.Intake Manifold 4V, single plane aluminum (For Holley 4500).Intake Manifold 4V, dual plane aluminum (For Holley ) Misc. Clearances and Specs for the Ford 351C Deck clearance for TRW piston. Piston to valve clearance Piston to deck volume TRW Combustion chamber vol. TRW. Gasket volume (D3ZZ-6051-A) Bearing clearances End play Valves. Piston Ring end gap Ring to groove (Grams) Bobweight (estimated) Reciprocating: main rod cam crank cam dist. shaft.stem to guide ex. in. lash in. & ex. to bore to pin comp. oil comp. oil Balance and Weight Information Piston Compression Ring (upper) 1 Compression Ring (lower) 1 Oil Ring 1 Piston Pin (C9ZZ-6135-A) 1 Conn Rod Assy (piston pin end) 1 Centrifugal: Conn Rod Assy (crank end) 2 Conn Rod Bearings 4 Oil in Crankpin Total Bobweight Less Equivalent External Bobweight of 27.3 oz. in. in Damper and Flywheel Crankshaft Bobweight min. 0 lash -8.6 cc 66.1 cc (mill 0.006" to reduce vol. 1 cc) 8.0 cc hot cold snug No. Required Stock TRW I They are not generally recommended. The Boss valve measure intake 2.19, 5.23 long, exhaust 1.71, 5.05 long. The part numbers are ex. DOzz-6505-A, in. DOZZ-6507-A. If you want to lighten up the valve train you might go back to Hank Manley's light-weight stainless steel valves. The head diameters are the same as stock but the stem measures 5h&". Obviously a valve guide sleeve must be installed with these valves. Manley recommends these valves to improve valve spring and camshaft life, and points out that the stainless valves feature a head shape that flows a great deal better than stock, titanium, and DECEMBER hollow-stem valves. His intake valve weighs just 100 grams, and the exhaust is a heavy 90 grams. The close matching of the weight is an added plus. The intake number is 11810, and the exhaust number is Manley Performance Engineering is located in Bloomfield, N.J. The Boss and H. O. engines come with pushrod guide plates and these must be added when converting hydraulic cam heads to mechanical cams. In addition to the factory units, Hank offers %" pushrods and matched Continued on page 64 51

351 = Sleeper Continued from page 51 hardness guide plates. The Boss valve springs weigh in at 315 Ib. @ 1.32" open.

5 351 = Sleeper Continued from page 51 hardness guide plates. The Boss valve springs weigh in at " open. For maximum reliability in any engine we recommend the practically indestructible Vasco Jet springs available from many outlets. (Ft.-Lbs.) Bolt & Nut Torque Specifications Cylinder Head-1st step nd step rd step th step 120-5th step 125 (hot torque) Main Bearing Cap Va % Main Bearing Saddle Width & Cap Fit Interference Con Rod Nut (with oil under nut) Oil Pan Bolt 1/ / Cam Thrust Plate to Block Bolt 9-12 Cam Sprocket to Camshaft Bolt Flywheel to Crankshaft Bolt Crankshaft Damper to Crankshaft Bolt Spark Plug (14 mm) Oil Filter Mtg. to Block Insert Carburetor Mtd. Stud 4-7 Carburetor Mtd. Nut Clutch to Flywheel Intake Manifold Attch. Bolt % /i Front Cover Bolt Water Pump to Front Cover Bolt Rocker Arm Mtg. Stud Distributor Hold Down Bolt Exhaust Manifold to Cyl. Head Bolt Valve Rocker Arm Cover Mtg. Bolt 3-5 One little goodie that is too good to overlook is numbered D2ZX-6670-A. This is the oil pump spring used to achieve 100 psi by-pass pressure. Also, rocker kit DOZX- 6A585-A includes needle bearing rockers with bearing assembly, bearing housing, nut, shaft, and set screw. When using quench heads TRW #L-2348-F piston gives you12.0:1 compression without decking. When this piston is used it is recommended that a small hole be drilled in the piston in the oil groove above the pin hole. Then drill a hole through the pin hole from the inside of the piston to intersect the first hole. This improves pin lubrication. For short-track applications the following recommendations apply: Bud Moore 302 Mini Plenum manifold (spacers are required) with Holley 750 or 850 double pumper, or an appropriate Weiand or Edelbrock manifold with a pair of Holley # cfm carbs. On long tracks try the Ford single-plane manifold D1ZX-9425-FA. Short tracks headers should use 2-1/a or 2-1/2 primaries at 38 to 40 inches with a 3-1/2 to 4" collector. For longer tracks the primaries may be shortened to 30-34". That wraps up the basic information we set out to provide on the 351 Cleveland. We hope this inspires more racers to try this engine which has strong potential. The following general installation torque specifications apply to operations not listed below. Thread Size Torque Ft.-Lbs. 'A V '/4-Pipe /i /i % % %-Pipe /i /i '/ V Va-14 Pipe /i Ve TOP At left is the ordinary 351 flat top piston. The pop-up piston at right gives a compression ratio of 10.6:1 with the quench head. Neither is the ticket for serious racing. RIGHT In full street trim the 351 Cleveland belies its potential. 64 STOCK CAR RACING

2013 Senoia Raceway Rulebook

2013 Senoia Raceway Rulebook E-mail tech questions to: johnnywalls31@yahoo.com BOMBER RULES BODY 1. All bodies must be stock steel bodies. No fiberglass or aluminum body panels allowed. Fenders and quarter