![]() Hot Rod Engine Tech 5. Dart BBC Race Build. The engine assembly stage typically includes multiple mock- ups or pre- assembly stages where the fit and compatibility of all internal components is checked and verified. Care must be taken to prevent component damage during mock- up, fitment, and final assembly. Prior to final assembly, perform a thorough cleaning and layout of all engine components to eliminate the possibility of dirt contamination and to ensure that all components are present, spotlessly clean, and ready for assembly. To prevent mistakes due to distraction it is also important to have on hand and lay out all of the necessary assembly lubricants and sealers and the various tools required to properly assemble an engine. The following are typically required for most engines. Proper engine assembly tools help maintain focus while building a racing engine. For this build we’re using a selection of engine building tools from ARP, Comp Cams, Proform, Snap- on, and Summit Racing. They include a set of micrometers, a cam installation tool, universal cam checking tool, digital scale, rod balancing tool, valve spring height mic, digital calipers, electric piston ring filer, and deck bridge. Torque Wrench. Ring Compressor. This web page has technical "how-to" information with photos regarding the procedures required to replace valve stem seals on a General Motors small block V8 with the. Chevy GM Marine Engines with 7-year warranty. For current prices and more information go to our Mercruiser listing. Most marine engines are made by GENERAL MOTORS. Dial Indicator. Dampener Installation Tool. Rod Bolt Stretch Gauge. Cam Installation Tool. Engine Assembly Oil. Engine Oil. ARP Ultra- Torque Lube. In these uncertain times, enthusiasts are forced to watch every penny, that's why we are trying to build a Chevy 350 engine with a set output of 400hp for only $1,000.Anti- Seize Compound. Loctite Thread Sealant. Loctite Threadlocker. RTV Silicone. Carb Cleaner. Brake Cleaner. Thread Tapping Lube. ARP Thread Sealer. Non- lint Paper Towels. Magnifying Glass. Engine Stand. Engine building requires attention to small details such as installing pin oiling jets in the main bore saddles prior to assembly. These preliminary preparation steps are often essential for maximum power and durability. Dart’s Big M Sportsman block features siamesed 4. Assembly Procedure. Our sample engine build is a 5. Chevy based around a Dart Big M cylinder block and Dart Big Chief Pro 1 aluminum cylinder heads. Following the step- by- step procedures is designed to simplify the mating of all the important components. Oil Gallery Plugs. After thoroughly cleaning the cylinder block and all of the individual engine parts you are ready to begin the final stage of engine assembly. Begin by installing the oil gallery plugs. Every engine is different, so be sure to identify the correct plugs for your particular engine. Apply a small amount of ARP Thread Sealer to each plug and install it snugly with a hex key wrench. At this time you may also want to install the core plugs in the cylinder block. Apply sealer lightly to each core plug and drive into the appropriate openings. The initial step in block preparation includes chasing all threaded holes with thread- chasing taps from ARP. This is particularly important to ensure proper seating of main cap and cylinder head studs. Check the depth of all head bolt holes to ensure adequate depth when head bolts are being used. Too little clearance can prevent proper clamping and initiate a blown head gasket. Cam Bearings. Carefully install the camshaft bearings. Our sample big- block Chevy is fitted with Comp Cam’s Composite Coated cam bearings. To help start the cam bearings, the cam housing bores were pre- chamfered with a 2½- inch ball hone attached to a drill motor. Carefully align them and drive them in place. Main Cap Studs. You can upgrade to ARP main cap studs for added crankshaft stability. To maintain proper fitment Dart recommends that the main caps and block mating surface be lightly deburred upon removal to ensure that the correct main size is maintained. To check the work, run a straight- edge through the housing bores and check all of them with a dial bore gauge prior to removal. These measurements are then compared to new ones taken after the main studs were installed and torqued. The goal is to maintain the proper housing bore measurement and the existing housing bore alignment. In our case, Dart’s precise main cap fit allowed us to make the swap with no misalignment. Main Bearings. Install the grooved upper main bearing shells into the block and verify alignment of the bearing insert oiling hole with the priority main oiling hole in each main web housing bore. Some builders grind the opening to match the bearing insert if the hole is partially blocked by the bearing being misaligned. On our build the bearing feed hole did not exactly match the opening in the block, but once the feeder grooves were cut for the pin oiler inserts, it all matched up correctly. Install the lower half- shells (ungrooved) in the appropriate main caps. During initial engine mock- up, the proper clearances were determined, and a combination of standard and 1- under Calico coated main bearings were used to achieve . Although we are using Calico coated engine bearings for added protection, high- pressure assembly lube on the bearings for the crank installation is still used. Some builders are careful to countersink the head- bolt holes after decking and surfacing to prevent misalignment and/or cracking. Carefully deburr the bottom of the cylinders after honing to remove sharp edges. The upper main bearing is always grooved. Inspect the back of the bearing for dirt or damage, then install it in the housing bore, pressing it down firmly by the parting lines. Install the ungrooved mate in the main bearing cap. ARP instructs that main studs and the corresponding threaded holes in the cylinder block be thoroughly cleaned. Then install the main studs finger tight. Do not overtighten them. If the studs do not fit properly, chase the threads with an ARP thread- chasing tap. A convenient place to check the crankshaft thrust is off the rear main crank throw adjacent to the thrust bearing. Rig a dial indicator horizontally and zero it at the top. Then use a pry bar to move the crank forward and backward to check the thrust. This crank checked at . Once the bearing’s shells are properly seated in the housing bores, apply lubricant and set the crankshaft in place. Rig a dial indicator to read off the front of the crank snout or from one of the crank throws and check the crankshaft thrust clearance. Crankshaft. After numerous mock- ups with setup bearings, the crank is usually contaminated. Clean it using small Moroso cleaning brushes available from Summit Racing. Brush all of the oil passages thoroughly. A common trick is to stand the crank upright in a rack and spray it down thoroughly with brake cleaner. It leaves no residue and the journals can then be wiped carefully with soft, shop (blue) paper towels that don’t shed. When you are satisfied that the crank is clean, install the rear main seal. If you have a two- piece seal, clock one half of it in the block so that one side protrudes by about 3/1. Lubricate the upper main bearings and carefully lower the crank in place. Clock the other half of the rear main seal in the opposite direction in the rear main cap, apply a thin bead of sealer to the parting faces, and carefully work the seals together as you install the cap. Apply assembly lube to the lower rear main bearing and install the rear main cap. Torque to recommended specs and turn the crank to ensure that it spins freely. Install the lower main bearings in each of the other main caps using assembly lube for lubrication. Torque all studs to spec and check the crank for freedom of movement. Camshaft. Lube the cam bearings and carefully slide the camshaft into the cylinder block taking great care not to scratch the cam bearings or nick the lobes on the block. For best results use a camshaft installation tool like those sold by Pro. Form. These tools bolt to the front of the cam and provide a cushioned handle that offers additional leverage so you can guide the cam easily into the block. Break- in motor oil is used for a lubricant because this particular engine has a roller camshaft. Flat- tappet camshafts normally require the application of a special camshaft break- in lubricant to the lifters and cam lobes to protect them upon initial engine startup. Many builders wait until the very end to install the rear cam plug, but it is better to install it early on to prevent accidental contamination via the exposed rear cam journal. Most engine stands permit this. The reciprocating portion of our power system is a formidable combination that includes Ross Pro Mod Nitrous pistons with high- strength pins and pin buttons, scat H- beam connecting rods, Calico coated rod bearings, and Speed Pro Hell.
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