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Road Tour EngineBuilding A Street Rod For The Long Haul...And It Could Be Yours From the February, 2009 issue of Street Rodder By Ron Ceridono Illustrators: Dominic Conti
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Every year for the past half-dozen, SRM has involved some of the best builders in the business in constructing a new, from the ground up, Road Tour rod. And while the form has varied from one to the next, the function of the various cars has always been the same: To show that the readily available components supplied by our advertisers will indeed deliver the reliable performance street rodders expect from them. To prove the point, a Road Tour car is built, then we strap Jerry Dixey in it and turn him loose on an unsuspecting public to drive coast to coast, border to border, attending all 11 NSRA events along the way. In a relatively short period of time that results in the accumulation of well over 20,000 miles, a real test of man and machine. And this year the Road Tour rod will test something else: Your luck. At the last NSRA event of 2001, in Tampa, Florida, we'll pick the lucky winner of the Road Tour rod. (The sweepstakes can be entered at any NSRA event, or by filling out the entry card found in these very pages.) While the focus of the Road Tour cars is always the same, this year's effort is unique for a variety of reasons; not the least of which is the 2001 version is the first to be based on an all-steel, gennie original. Starting with a pristine '36 Chevy, CarFab in Concord, North Carolina, along with a host of suppliers, is transforming the stock sedan into an eye-popping road warrior. But while this tour car may be different than past efforts in some respects, due to the rigors of the road they're all exposed to, a reliable powerplant is always at the top of the needs list for them all. This year that need was capably filled by Performance Automotive Warehouse (PAW). When selecting an engine for any street rod there are a variety of options, but what we were looking for was something beyond the ordinary. An affordable, custom-built engine that can be duplicated by just about anyone. Thumbing through PAW's 1,200-plus page catalog we found just what we were after in one of their complete small-block Chevy engine kits. Along with all the first-class parts necessary to build a stout street engine, the block has received the same attention to detail a factory engine is treated to, plus the entire rotating/reciprocation mass has been custom balanced. Dubbed the 350 Chevy Special, the kit comes complete with a four-bolt main block that has been decked, line honed, bored .030-inch oversize, honed for moly rings, painted inside and out, and fitted with new cam bearings and brass soft plugs. Also included in the kit was a custom ground crankshaft, Magnafluxed, shot-peened, resized rods fitted with chrome-moly rod bolts, TRW forged pistons, moly rings, Comp Cams cam, lifters, pushrods, double roller timing chain and sprockets, high-volume oil pump, and long slot rocker arms. Topping it all off are World Products SR Torquer heads along with an Edelbrock intake manifold and carburetor. The Tricks it Takes to be Trick
One of the advantages of building an engine the way we've done it with our PAW small-block is the opportunity to apply the time-honored tricks and attention to detail that standard production line engines aren't treated to. For those who may have heard some of the common terms that relate to building an engine, but may not be exactly sure what they mean, here is an overview of the operations involved in building a custom engine that PAW routinely uses. Line Honing: To allow the crankshaft to rotate in the block smoothly with as little loss to friction as possible, it is critical that the main bearing bores be in perfect alignment; line honing ensures that. The process consists of taking a few thousands off the surface of the main bearing caps, then they are reattached to the block and the main bearing bores are honed to the exact diameter and as a result are in perfect alignment. Decking: It is not unusual for the deck height (the distance from the centerline of the crankshaft to the head gasket surface of the block) to vary from one end of the block to the other. The result is the pistons come closer to the deck in some cylinders than others; that means there is a difference in compression and power production between the cylinders. PAW machines the head gasket surface of their kit blocks, which is called decking, to insure the surfaces are flat to facilitate head gasket sealing, and parallel to the crankshaft centerline. Honing: Basically there are three types of rings: cast, chrome, and moly. Cast rings break in fast and are good for less than perfect cylinders; chrome rings are best suited to dirty environments but can take a long time to break in; moly rings (called that because the face of the top compression ring has a groove filled with molybedenum disulfide) break in fast and provide excellent sealing. As one might expect, just as the rings differ, so do the cylinder wall finishes they require. Using the ground-up kit approach allows the engine builder to specify the type of rings desired as well as the cylinder wall finish to suit specific applications. Connecting Rod Preparation: One of the most critical components in an engine are the connecting rods. Few things are more catastrophic than a rod failure, so special attention should be paid to them. Prepping rods begins with Magnafluxing to check for cracks and then they are fitted with high-strength rod bolts. Next the diameter of the small ends are checked and the big ends are resized by removing a small amount of material from the rod and cap mating surfaces, bolting them back together, then honing them to the proper inside diameter. This ensures proper bearing crush, which is what prevents the bearings from spinning in the rod. Shot-peening is done to compact the outer surface of the rods and reduce the tendency for surface cracks to develop. Finally the rods are checked in a special fixture to ensure they are straight in all planes. Balancing: The key to a smooth, long-lasting engine is balancing. Custom balancing also allows for the substitution of different components. As an example, when stronger forged pistons are substituted for the stock cast, the difference in weight can be taken into account when the crankshaft is balanced. Crankshaft Grinding: Generally considered a repair procedure, grinding the crankshaft journals undersize (normally .010, .020 or .030-inch) removes any imperfections and ensures the journals are smooth and round. Getting It All Together
To assemble our kit we called on the experienced crew in PAW's machine shop. An old hand at such chores, they agreed to do the deed. Next we dispatched Dominic Conti with camera in hand to document what it takes to build an engine to withstand the rigors of Road Tour. Follow along as the build-up of our '36 Chevy, which just might end up in your garage, begins.  The assembled PAW small-block...  The assembled PAW small-block Chevy at home between the rails of the Road Tour 2001 '36 Chevy. The 355-inch small-block will utilize a K&N air cleaner, Edelbrock carburetor, manifold and water pump, and Alan Grove pulleys and brackets. Valve covers are Moroso; headers are Hedman that blow through Spin Tech Performance mufflers; and fuel is delivered through lines from Classic Tube. Electrics consist of a starter and alternator from Power Master and distributor and wires from MSD. Cooling is handled by a Walker radiator, Cooling Components electric fan, and a Mullins' overflow tank. The Jet 700-R4 transmission's temperatures are kept in check by a Flex-a-lite cooler and is shifted by linkage from Kugel Komponents.  One of the first steps to...  One of the first steps to a precision engine build is line-honing the main bearing bores, obviously an operation that requires specialized and expensive equipment. This operation guarantees the alignment of the main bearing bores is perfect to eliminate unnecessary friction.  Decking is an important part...  Decking is an important part of the rebuilding process--it ensures the head gasket surface is perfectly flat and parallel to the crankshaft centerline. Note the block is attached to the machine by a fixture that runs through the main bearing bores--that's one of the reasons they must be in perfect alignment and why line honing is an important step in the process.  A Sunnen CK-10 hone is used...  A Sunnen CK-10 hone is used to establish the exact size of the cylinders. Specific stones are used to provide the finish necessary for the type of rings that will be used. Here, the diameter of the bore is being checked.  Critical components in a true...  Critical components in a true high-performance engine are the connecting rods. PAW gives them the complete treatment as they are Magnafluxed, shot-peened, fitted with high-strength bolts, and then balanced. Here, the inside diameter of the big end is checked after the resizing procedure.  With the weight of the pistons,...  With the weight of the pistons, pins, rings, and rods established, bob-weights are attached to the crankshaft's rod journals. The crank is spun with the weights in place to determine the heavy spots, then a drill is used to remove material from the counterweights to bring the shaft into balance.  One of the advantages of PAW's...  One of the advantages of PAW's engine kit is the inclusion of top quality parts. Here, moly rings are being installed on the TRW pistons. While there is no substitute for experience, assembling an engine is within the capabilities of most enthusiasts. A few special tools and a manual specific to the engine will help, and the best part is you can say you built it yourself.  To ensure Dixey can run with...  To ensure Dixey can run with the big dogs, we picked an optional performance cam from Comp Cams. This particular stick has .447/.454-inch lift intake and exhaust; advertised duration of 256/268 intake and exhaust (212/218@.050-inch) on 110-degree lobe centers.  Another performance part not...  Another performance part not generally found in production engines is a true roller timing chain. Some look like roller chains but actually use split bushings instead. Here, the alignment of the timing marks is being checked.  The first step in balancing...  The first step in balancing the pistons is weighing them individually. Then weight is removed from all those that are heavy, as shown here, until all match the lightest in the set.  Another important step in...  Another important step in building a precision engine is degreeing the cam. Although it's not a particularly difficult operation, this procedure ensures relationship between valve movements and the position of the pistons in the cylinder. Corrections are made a number of ways--offset bushings between the cam sprocket and the alignment pin in the cam are commonly used on Chevrolets.  Prior to assembly, the block...  Prior to assembly, the block was painted inside and out and brass soft plugs were installed. Along with grinding and balancing the crankshaft, the journals are treated to a micro-polish finish and the oil holes are chamfered.  A trick little item from PAW...  A trick little item from PAW we included on this engine is this cam screw lock plate. The tags are simply bent over against the head of the capscrews to mechanically lock them in place.  Although we used a high-volume...  Although we used a high-volume oil pump, we used a stock Chevy pickup. Here, a special installation tool is used to drive the pickup into the pump. Properly positioned, the screen will be approximately 3/8-inch from the bottom of the pan.  A common modification made...  A common modification made to Chevy oil pumps is tacking the pickup tube to the body. The bottom of the pump should be removed and the bypass spring taken out during the welding process.  To make sure the Road Tour...  To make sure the Road Tour engine looks as good as it runs, a few chrome accessories, such as this PAW timing chain cover, were installed. Also included was a bolt-on timing pointer. Covering the bottom of the small-block is a Hamburger/TD Performance plated pan.  As we've shown one of the...  As we've shown one of the major advantages of building a kit engine is the opportunity to check every detail during assembly. Here the valve springs are being tested to ensure they meet specifications at both open and closed heights.  With the valve spring pressures...  With the valve spring pressures verified, the next crucial measurement is the installed height. This is determined by measuring from the underside of the retainer to the spring seat in the head.  We opted to use the optional...  We opted to use the optional World Products SR Torquer heads on the Road Tour engine. These cast iron heads are fitted with stainless Manley Street-Flo valves, 2.020-inch intake and 1.60-inch exhaust. Intake ports are 170cc to insure strong bottom-end and mid-range performance.  With the heads torqued to...  With the heads torqued to specs, we stepped up for a pair of options--an Edelbrock manifold and ARP 12-point fastener kit to hold it on. Pushrods and rockers are from Comp Cams.  Built from the best parts,...  Built from the best parts, precisely machined and expertly assembled, here's the Road Tour small-block all done and ready to run. And the best part is the engine, and the '36 Chevy it's going in, can be yours!
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