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427W Raptor Engine Buildup - E=MCE2Part 1 In A Two-Part Series From the March, 2010 issue of Modified Mustangs & Fords By Jim Smart Photography by Jim Smart
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Never before have we learned more about engine building and power production than we have with Marvin McAfee and MCE Engines. That said, we're about to learn something refreshing about how to look at how power is made. When we're planning our engine projects, we don't give enough thought to how power is made. In fact, as bench racers, all we can think about is high-rpm, foot-to-the-floor horsepower. However, there's a whole lot more to performance than just horsepower. There's also torque and durability. Torque is your daddy on the street. And without durability, all the horsepower in the world won't help if you scatter engine parts all over the asphalt. We have an M-6010-N351 Ford... We have an M-6010-N351 Ford Racing block. The casting number reads E6ZM-6015-G351 with a casting date code of "6D10" or April 10, 2006, cast at the Windsor Iron Foundry. When you're planning an engine build, the first question to ask yourself is what do you want the engine to do? When MCE Engines was planning the 427 Raptor, Marvin knew exactly what he wanted the engine to do-and, when we went to the dyno at Edelbrock, it did exactly what he expected it to do. Being magazine guys with bold cover headlines in mind, we were thinking 600-650 hp and 600 lb-ft of torque because these are numbers that sell magazines. And, these are very typical numbers for street-going, weekend-racing 427ci small-blocks that go together in car magazines. However, this isn't what Marvin had in mind. MCE Engines had torque, durability, and horsepower in mind and exactly in that order of priority. Marvin will pointedly tell you power isn't worth a damn without durability. And if given a choice between power and durability, Marvin will go for durability any day because you can build more power into durability. We will tell you the road to the dyno wasn't an easy one. We got into intense conversation with Marvin about power because we were seeking at least 600/600 and Marvin was thinking more like 550/550. Marvin was thinking of road racing and we were thinking of awe-inspiring circulation numbers from hot cover blurbs. Bench racing logic was, if 550 was enough, then why wouldn't 600 be even better? Marvin smiled, then, invited us to patiently wait for the dyno room. Because this is a race block,... Because this is a race block, Ford Racing has done a lot of our thinking for us. Screw-in oil galley plugs are standard. Cylinder and lifter bores are unfinished, which enables Marvin to lay down a custom bore and hone for exceptional cylinder sealing. The N351 block has thicker decks and plenty of meat around each cylinder bore for a stable foundation. Our argument with Marvin about desired horsepower numbers really wasn't our fault. Madison Avenue has been brainwashing us for a century about horsepower. Horsepower always has the spotlight whenever a new car or truck comes out or when car magazines build engines. We all promote horsepower. However, horsepower isn't always the most important dynamic, especially on the street and certainly in road racing. Horsepower is a key element in drag and stock car racing at high rpm. On the street and in road racing, we need abundant low- and mid-range torque, because that's where our engines operate most of the time. Torque is what gets us started at the traffic light and onto a freeway. Torque is also what spanks the other guy when we're flexing muscles from traffic light to traffic light. Torque is what launches. Torque is also what gets the road racer out of a turn and back up to speed in short order. Torque is fundamentally nothing more than shear grunt, the kind of power you make with your upper leg muscles. And once torque gets us going, it hands off to horsepower at high rpm where an engine takes off like a bat out of hell. In a road-racing engine, we need liberal amounts of both torque and horsepower. We need an engine that can do both without faltering or breaking.  The N351 block's No. 5 main...  The N351 block's No. 5 main is designed for a one-piece rear main seal. Marvin will use Clevite H-Series race bearings to complement the 4340 steel stroker crank with increased journal radiuses from Coast High Performance/Probe Industries.  Marvin has a strict regimen...  Marvin has a strict regimen he follows with every engine he builds. All oil passages, both pressurized and drain back, are massaged to improve flow and reduce fluid turbulence. Marvin also removes all iron casting stress risers, which can lead to cracking and sliced fingers.  All oil galleys are chased...  All oil galleys are chased thoroughly and threaded for screw-in plugs at MCE Engines. The top oil galley has already been threaded by Ford Racing. Marvin has chased and massaged this crossover passage for improved flow.  Marvin massages all oil drain...  Marvin massages all oil drain back passages to expedite oil return. He will also paint all inside surfaces with GE Glyptal from The Eastwood Company, which seals all unmachined surfaces and improves return oil flow. He also uses oil restrictors to reduce cam bearing/rocker arm oil flow and increase flow to the main and rod bearings.  Marvin's discipline includes...  Marvin's discipline includes chasing all bolt holes with a bottom tap as shown. This improves fastener performance and makes for accurate and uniform torque readings.  Marvin's policy is easy to...  Marvin's policy is easy to understand and follow-trust, but verify because where there are humans involved, mistakes will happen. Just because a part is new doesn't mean it is free of defects. Marvin inspects and blueprints every part. Blocks are completely stripped down including Welsh and oil galley plugs. Marvin has unearthed lots of machining trash and iron particles from every single casting he's ever worked. Here, he finds stray iron from factory machine work hidden behind the Welsh (freeze) plugs. Iron particles like this can plug smaller cooling passages and create hot spots, which raise hell in the water pump and restrict radiator cooling tubes. What Works . . .
When Marvin sat down to pencil out his 427W Raptor project, he knew exactly what he needed this road-racing engine to do. Architecturally, he needed a brute block that would stay together, which meant a stock 351W block would never do for an engine expected to make 550-600 horsepower and turn 6,500-7,500 rpm. We contacted Ford Racing and ordered an M-6010-N351 wet-sump block, which is perfect for road or drag racing thanks to a four-bolt main design, higher nickel content for strength, 2.749-inch main journals, non-siamese bores, thick nodular iron main caps, heavy-duty webbing for incredible strength, semi-finished cylinder and lifter bores, thick decks, 9.500-inch deck height, and a 4.000-4.030-inch bore range. Marvin checks main caps for... Marvin checks main caps for a perfect interference fit. H-Series main bearings are also checked for proper fit meaning just the right amount of crush. Marvin's plan for power was common sense-raw street smarts of how power is made. No matter what the hot shots will tell you, power, durability, and cash flow are all about compromise. To have a whole lot of one thing, you must sacrifice from another. Marvin subscribes to the air pump theory of how an engine makes power. How much air and fuel can you huff into each bore and light off as the piston reaches top dead center? If you want boatloads of horsepower at 7,500 rpm, you will sacrifice torque. And if you want low-rpm grunt out of a traffic light, you're going to give up horsepower. It is the age-old rule of physics and how horsepower and torque dance with each other. When it's time for Marvin... When it's time for Marvin to send his N351 block to Team C in Bellflower, California, for machine work, communication is concise and clear. He writes everything he wants the machine shop to know on the tag. And when he arrives with the block, he's clear about what's expected. And when he picks up the block, he will check all tolerances. If anything is out of spec, the block goes back for corrective action. No matter what kind of Otto four-cycle internal combustion engine you're thinking of, horsepower and torque pass each other at 5,250 rpm. This formula is "horsepower equals torque times rpm over 5,250 rpm. But, what really matters is how horsepower and torque respond before and after 5,250 rpm that counts. The ideal situation is to have a broad torque curve where an engine pulls like stink as early as possible and remains strong as close to peak horsepower as possible. What's more, you want an engine to make the most power possible at the lowest rpm range possible, which is where durability comes in and keeps you in the race. If your engine is making 650 horsepower at 7,500 rpm, but comes unglued all over the track before reaching the finish line, where's the benefit? No one remembers the poor slob who finishes twelfth who was leading the race early on. When Marvin was planning the Raptor, there were skeptics, including one cylinder head manufacturer who said we'd never clear 500 horsepower with the Erson mechanical roller cam Marvin had chosen. In fact, we were also among the skeptics who said it probably couldn't be done. This is when Marvin became very determined to prove his point. He chose the Edelbrock/Glidden/Victor Pro-Port CNC Raw cylinder head (No. 61099) in combination with the port-matched Super Victor intake (No. 2924) for the Raptor project because, in his opinion, it was ultimately the best cylinder head for the job. Marvin saw room for growth in the Edelbrock/Glidden/Victor CNC Pro-Port head where anywhere from 500 to 750 horsepower could be made depending upon cam selection, compression, and carburetion. Valve selection is as crucial as cylinder head type, port and chamber design. "Don't cut corners on valves," Marvin stresses, "Manley Performance has got you covered from dead stock to high-end racing." Manley can make a custom dimension valve for your engine project, which is something not all manufacturers do. Start with Manley's catalog and fill out the spec sheet with your requirements. Marvin decided to go with hollow-stem stainless steel valves for the Raptor project. Lightweight titanium valves would have been cost prohibitive. The E=MCE2 formula is about growth-building one heck of a foundation on which you can grow, and that's what we're doing here. If your objective is 500-550 horsepower, you have a solid foundation that will live to see a lot of action. If your plan is an all out drag racing engine with 650-750 horsepower, expect shorter engine life and yet tremendous power.  Marvin opted for the No. 10027...  Marvin opted for the No. 10027 4340 steel crankshaft from Probe Industries along with 6.250-inch 4340 H-beam rods (No. 10082). Because the N351 block calls for a smaller 2.750-inch main journal, we're going with a 351C crankshaft, which has this main journal size. And this is the main journal size you want with the N351 block.  As with the block, heads,...  As with the block, heads, and other components, Marvin goes over the 4340 steel crank thoroughly looking for flaws. All oil passages are examined and chased with soap, water, and a drill-powered rat-tail brush to remove any debris. Then, the crank is immediately soaked with WD-40 to prevent corrosion.  The Fel-Pro one-piece high-performance...  The Fel-Pro one-piece high-performance rear main seal provided by Summit Racing Equipment is gently fitted as shown. Marvin dresses the seal with assembly lube around its inside perimeter, which ensures plenty of lubrication on start-up. A dry seal on start-up will overheat from friction and induce seal failure.  When you're going to run an...  When you're going to run an engine hard, use H-Series bearings with your 4340 steel crankshaft. Notice Marvin has massaged oil galleys for improved flow.  Marvin stresses never using...  Marvin stresses never using assembly lube or engine oil between bearings and block and bearings and rods. Surfaces must be bone dry for good crush and secure fit. However, bearings and journals get liberal doses of Marvin's own special mix of engine assembly lube, which has staying power.  Marvin sets the crankshaft...  Marvin sets the crankshaft with the rear main seal installed for best results. He closely examines the inside lip to ensure there's proper sealing. A smooth marriage between... A smooth marriage between journal and bearing is where longevity comes from. Marvin goes to extremes here-measuring journals and bearings, then, establishing exact clearances. He stresses having a good oil wedge, plenty of clearance (yet not too much or too little), and uniformity for 360 degrees. High spots on a bearing create hot spots and wear issues. Marvin calls these tall claims of 600-650 horsepower on pump gas as laughable because they are not true. To make brute horsepower and torque numbers, you must have compression and abundant airflow, which translates into whopping cylinder pressure and power. You must also have octane that will stand up to high cylinder pressures without detonation. There are no free lunches, Marvin stresses, when it comes to power. You're going to have to give up one thing to have more of another and there are no exceptions. He adds if you decide to cheat and go with nitrous or supercharging, you will sacrifice durability. When you can touch a button and get 150-200 horsepower, you will hammer the daylights out of an engine, Marvin offers with a snapper. Marvin canvassed cam manufacturers for just the right combination of lift, duration, valve overlap, and lobe centers. He wanted something off the shelf anyone could buy. He found exactly what he was looking for at Erson Cams, a drag racing cam profile that offered him the smooth combination of torque and horsepower. And had Marvin been willing to go with a custom grind, he could have improved horsepower and torque numbers significantly. However, Marvin's madness is rooted in building something anyone else could build using off-the-shelf parts readily available to anyone. In his opinion, that makes things fair. Erson Cam Snapshot
Part Number: E212991 with 1.050-inch (small) base circle.
Grind Number: R-278-2 (Intake/Exhaust)
Lobe Separation:112-Degrees +4
Lift: 0.592-inch (Intake/Exhaust)
Advertised Duration: 278/286 ‚degrees (Intake/Exhaust)
Duration at 0.050-inch: 238/246 degrees  Marvin has a unique system...  Marvin has a unique system of torquing fasteners. Main caps get torqued in three phases for proper seating and alignment, checking for smooth crank rotation, proper clamping, and bearing crush between torque phases.  When main cap fastener torquing...  When main cap fastener torquing is complete, Marvin checks crankshaft endplay, which should be 0.004-0.008-inch. Ideally, you will have 0.006-inch.  Marvin's disciplined routine...  Marvin's disciplined routine includes checking volume above the piston or "cc'ing" chambers, piston domes/dishes and valve reliefs, deck height, and head gasket thickness to ascertain exact static compression ratio.  As with main bearings and...  As with main bearings and journals, rod bearings and journals must have a happy marriage.  It is incredibly easy to install...  It is incredibly easy to install rod bearings backwards or not set the bearing properly. Do not make this mistake. Make sure bearing shoulders/radiuses follow rod journal shoulders. And remember, the bearing tang is there for proper alignment, not security. What holds the bearing is a good, dry crush.  Our Probe Industries 4340...  Our Probe Industries 4340 H-Beam rods are secured with 7/16-inch cap screws, which clamp better than pressed-in rod bolts and nuts. Torque is 70 lb-ft, or 0.006-inch bolt stretch using moly lube.  There's always plenty of stress...  There's always plenty of stress on crankshaft endplay, but not enough of us check camshaft endplay, Marvin tells us. Cam endplay should be 0.002-0.006-inch. However, 0.004-inch is desired.  Marvin checks for true top...  Marvin checks for true top dead center, which helps determine exact cam timing and piston-to-valve clearance. The Raptor's true top dead center yielded 0.187-inch of piston-to-valve clearance cold for both intake and exhaust.  This is Marvin's finish work,...  This is Marvin's finish work, with screw-in oil galley plugs and GE Glyptal.  To achieve perfect fit between...  To achieve perfect fit between the Edelbrock/Glidden heads, Super Victor intake manifold, and N351 block, Marvin fabricated special spacers for the block ends.  All fasteners should be lubricated...  All fasteners should be lubricated with engine oil, anti-seize, or molybdenum grease. This, coupled with thread chasing, makes for smooth, accurate fastener tightening.  Erson Cams set us up with...  Erson Cams set us up with a mechanical roller camshaft designed primarily for drag racing. It will yield a sweet combination of both torque and horsepower. Bank on a broad torque curve nearly equal to horsepower when rpm rises. Crane Cams provided us with shaft-mounted 1.6:1 roller rocker arms.
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