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Edelbrock MCE Engines 427W Raptor Stroker Project Part 2Part 2 In A Two-Part Series From the May, 2010 issue of Modified Mustangs & Fords By Jim Smart Photography by Jim Smart
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Tech | Engine Building
We Wrap Up Our Edelbrock/MCE Engines 427w Raptor We began our Edelbrock/MCE Engines 427W Raptor stroker project with elements important to making power in the March 2010 issue. This month, we're going to wrap up our project with important points to releasing power wasted inside your engine. They don't always involve cam specifications, carburetor sizing, and cylinder head flow numbers. Marvin McAfee of MCE Engines in Los Angeles, California, stresses you must go looking for trapped power inside an engine. Marvin wants the most airflow... Marvin wants the most airflow possible from manifold to port to combustion chamber.... Marvin's strategy for power includes internal friction reduction, reducing windage, improving oil return flow (scavenging), playing with valve timing, making finite adjustments to valve lash, and making modifications to induction and exhaust. He likes to get clearances to where they aren't too small yet they're not too large either. He wants liberal oil flow across bearing journals, yet he seeks a healthy oil wedge to keep moving parts happy. He likes his engines to have loose tolerances to free up trapped power, yet he likes things snug for durability. Put your hands on the crankshaft in one of Marvin's blocks and give it a twist while it's on the stand. Rotary motion in Marvin's engines is buttery smooth-easy to turn, yet comfortably snug. Slide a timing gear onto the crank and feel unequalled smoothness because everything with Marvin is zero fit void of resistance. Put your mallet away because you won't need it. ....However, he also seeks... ....However, he also seeks durability with sufficient valve seat contact for adequate valve cooling.... Marvin's engine blueprinting regiment is a strict discipline he follows with every engine he builds-extreme attention to detail that begins with the teardown and close forensics analysis. This comes of Marvin's extensive racing background coupled with a career in aviation. Failure analysis is his specialty. If an engine failed, Marvin wants to know why. Engine failure can lead to engine failure again if you miss something important to its foundation, Marvin will tell you. A crank or rod that isn't true; a block with misaligned main saddles; a warped deck, cracked castings; fasteners that should be replaced; and a host of other things we haven't thought of. Marvin will tell you it isn't always the obvious, but the unobvious, that leads to engine failure. Marvin blueprints every oil pump, checking rotor clearances in every way imaginable. He likes a nice, smooth slide fit along with proper spring pressure when he checks the pressure relief valve. Marvin wants at least 10 pounds of oil pressure for every 1,000 rpm along with volume with the engine hot. Raising pressure to increase volume will cost you power. ...You want valve seat width... ...You want valve seat width right on the edge of flow and durability.... When Marvin gets parts back from his machinist, he goes over everything with a fine-tooth comb, measuring all dimensions and inspecting machine work in great detail. Screw-in oil galley plugs are installed where press-in plugs existed. All oil galleys and water jackets are chased thoroughly to rid debris. Brass core plugs (also known as Welsh plugs) are installed with an industrial adhesive. Internal surfaces are coated with GE Glyptal to improve oil return flow. Ragged edges, known as stress risers, or radiuses are chamfered to prevent cracking. Components are checked for proper fit again and again during pre-assembly (mock-up) and assembly. The Edelbrock Glidden/Victor Pro-Port Cylinder Head
The Edelbrock Glidden/Victor CNC Small-Block Ford cylinder head is a replication of the head Billy Glidden designed and used for record drag racing numbers in NMRA competition. The Glidden/Victor casting was born to make the most of the 289/302/351W Ford V-8s. Because these castings come from Edelbrock's own foundry and machining processes, you know you're getting the best American quality possible. MCE Engines has prepared these head castings, massaging in significant improvements to improve durability. No additional port work has been performed though. Marvin opted for Manley hollow-stem stainless steel valves for his Edelbrock Glidden/Victor heads because they power the winners. And as we all know, everyone loves a winner. ....All the power in the world... ....All the power in the world is pointless without durability. Remember, you want an engine that's going to finish the race. "One sales/technical representative at a prominent cylinder head manufacturer said we'd be lucky to reach 500 horsepower with the cam we had chosen," Marvin tells us. "Achieving 600 horsepower is a no brainer. A more aggressive camshaft will get you there with this engine package. But 600 horsepower isn't what we're seeking here. Our goal is 550/550 on torque and horsepower-a nice compromise in our quest for both road racing and durability." Marvin went on to say, "I can't say enough about both Manley Performance and Edelbrock. These guys give you from mild street performance all the way to extreme duty, and they do it so well."  The number on the exhaust...  The number on the exhaust valve identifies its weight, which is 110.2 grams, destined for No. 5 cylinder. The "200" denotes spring pressure in pounds at installed height. The highest spring pressure goes to the heaviest valves because there's more weight there. This is where true "blueprinting" comes into play, those pesky details many builders typically miss.  We're going with Fel-Pro steel...  We're going with Fel-Pro steel core head gaskets with the pre-flattened copper fire rings (PN 1011-2) for the Raptor 427W, which provide excellent head-to-block sealing. Never use steel fire ring head gaskets because they will brinnel the soft aluminum head surfaces. Fire rings at each cylinder bore provide exceptional cylinder-head-to-block sealing with proper cylinder head torque and retorque. Marvin has had the block and head decks milled to perfect flat and true surfaces.  Marvin dresses mating surfaces...  Marvin dresses mating surfaces for smooth installation and fit. Timing components, which are coated in a low-friction coating, glide right on. Erson linked roller lifters... Erson linked roller lifters have been examined for flaws and blueprinted. Marvin has also dressed them with a low-friction coating for improved protection at start-up. In Marvin's quest for power, he wanted clean airflow beginning at the plenum, transitioning smoothly to ports, bowls, and valves. And this is what he achieved with Edelbrock Glidden/Victor heads and Super Victor induction. Valves and seats must have a clean transition to keep air turbulence minimal. This means a valve seat insert where there's no overhang or ragged edges-pesky zones that disrupt airflow. Valve guides need to be out of the way where there's no turbulence around the stem. This is where good port and bowl work is crucial. Intake manifold gaskets and ports must be right sized where there's no turbulence generated as the air/fuel mixture passes from manifold to cylinder head. By the same token, you want clean exhaust passages where turbulence is kept to a minimum and scavenging is thorough.
| Specifics |
Description |
| Part Number |
61099 (bare) |
| Combustion Chamber Volume |
61cc |
| Intake Runner Volume |
280cc |
| Exhaust Runner Volume |
94cc |
| Intake Valve Diameter |
2.15-inches |
| Exhaust Valve Diameter |
1.56-inches |
| Valve Stem Diameter |
11/32-inch |
| Valve Type Used |
Manley hollow stem stainless steel |
| Valve Guides |
Manganese bronze |
| Deck Thickness |
5/8-inch |
| Valve Angle |
15-degrees |
| Exhaust Port Location |
2 1/2-inch spread, raised 0.520-inch |
| Spark Plug Fitment |
14mm x 3/4-inch reach with gasket seat |
Crane shaft-mounted 1.6:1... Crane shaft-mounted 1.6:1 rockers (PN 44809-1) provide exceptional stability at high rpm. This was a more preferable setup compared to stud-mounted rocker arms. Marvin sets up valvetrain geometry where roller tip travel and valve stem are dead perfect. This is what you want for your valvetrain, void of any side loads on the valve stem.
Holley 4150 (0-80513-1), 1000cfm
0.84/0.84 Jetting
12.54:1 Compression
2-inch x 30-inch x 3 1/2-inch Hooker Headers
36 Degrees BTDC Total Ignition Timing
| RPM |
HP |
Torque |
| 4,000 |
399.3 |
524.3 |
| 4,500 |
467.0 |
545.1 |
| 5,000 |
513.6 |
539.5 |
| 5,500 |
541.5 |
517.1 |
| 6,000 |
551.1 |
482.5 |
| 6,500 |
541.2 |
437.3 |
| 7,000 |
522.5 |
392.0 |
Marvin blueprints his oiling... Marvin blueprints his oiling system components, which include a Melling (PN MEL-M83HV) high-volume oil pump along with a Canton front sump pan with windage tray, pick-up,.... We learn from this first pull Marvin's expectations were in line with what this engine made in Edelbrock's dyno lab. He predicted 550/550 and got it. Because this is a road race engine, torque is just as important as horsepower. What you don't see on this first pull, which begins at 4,000 rpm, is this engine's broad torque curve. Torque begins to come on strong around 2,500 rpm, peaking at 545.1 lb-ft at 4,500 rpm. Torque hands off to horsepower at 5,500 rpm, which tops out at 551.1 at 6,000 rpm. Most surprising is 551 horsepower at six grand, which means durability. With this engine, you get it all. In road racing and canyon cutting, you want torque to get you out of the corners and horsepower to blast you through the straights. You may find these numbers disappointing, especially if you're a drag racer, but consider this. Performance is rooted in what we want the engine to do, and we're going to talk about that shortly. If you're building a road race or street engine, you want a nice balance of torque and horsepower. You want a seamless transition from a mid-range torque peak to horsepower as your engine heads into the highlands. Team MCE concluded from this first pull the Holley 4150 needed larger 0.85 jets for the next pull to optimize air/fuel ratio. ....and road race baffles... ....and road race baffles to keep oil where it belongs in those hard corners. We're running an ARP oil pump shaft (PN ARP-154-7901) from Summit Racing. Canton products are available from Mustangs Plus. "Every engine has its sweet spot," Marvin comments. "We've worked with ignition timing and centered our limit at 36 degrees BTDC." He adds, "We could take it to 38 or 40 degrees BTDC and make more power, but be risking durability." Marvin stresses the difference between a dyno cell and real world conditions. Real world on a racetrack at speed put stresses on an engine we don't see under dyno cell conditions. Keeping timing conservative reduces the possibility of engine damage. "And here's another tip," Marvin adds, "maximum cylinder pressure occurs within five degrees of top-dead-center (TDC), which means you want the light off to begin at approximately 36 degrees BTDC." "The single greatest power builder is compression ratio," Marvin tells us. "Add compression and you add power." This is the cheapest, fastest way to increase power while keeping octane requirements in mind.  This is the Edelbrock Super...  This is the Edelbrock Super Victor (PN 2924) single-plane intake manifold for the 351W Ford topped with the Victor/Glidden cylinder heads. This is a high-flow manifold designed for high-rpm, which means it will work with our current cam/head combination or with even more aggressive valve timing events. Marvin has modified the plenum for even better airflow by reducing turbulence. A 2-inch open Edelbrock (PN 8712) phenolic spacer improves low to mid-range torque, giving this engine a brute torque curve.  This is Holley's 170gph (PN...  This is Holley's 170gph (PN 12-289-25) mechanical fuel pump designed specifically for the kind of power Marvin intends to make with the 427W Raptor. Shutoff fuel pressure is set for 6.5 to 8.0 psi. Bulletproof aluminum and steel construction makes this pump perfect for high rpm use. Inlet and outlet are tapped for 3/8-inch ID lines. For this kind of power, you want a minimum 3/8-inch ID line to handle the demand.  Marvin wanted to experiment...  Marvin wanted to experiment with two carburetors-the 1,000cfm Holley (PN 0-80513-1) race carburetor sporting down-leg boosters. This is a terrific out-of-the-box atomizer from Holley, with the quality and know-how you expect from them. MCE Engines had to dial this carburetor in for the 427W Raptor with the right 0.84/0.84 jetting for starters.  This is the 1,000cfm Holley...  This is the 1,000cfm Holley (PN 0-80514-1) carburetor from Performance Carburetors, which includes a custom blueprint, down-leg boosters, and special metering blocks. We're going to try both carburetors out of the box to see what they do on Edelbrock's dyno.  Summit Racing Equipment set...  Summit Racing Equipment set us up with a Powermaster high-output single-wire, internally-regulated 100-amp alternator (PN PWM-8-57100) with 5-inch diameter Summit pulley (PN G-3969). This keeps alternator rpms safe when the engine is at high rpm.  MSD to the rescue with its...  MSD to the rescue with its Pro-Billet (PN 8578) electronic distributor, which yields a compact design (5/8-inch smaller in diameter than a stock Ford distributor) that fits nicely thanks to a smaller cap and GM-style rotor. MCE Engines has dialed in a custom curve suitable for a road-race engine like the Raptor. MCE Engines has custom blueprinted... MCE Engines has custom blueprinted all of these parts for improved durability. The water pump, timing cover, and thermostat housing have been massaged internally to reduce fluid turbulence and hot spots.
Holley 4150 (0-80513-1), 1000cfm
0.85/0.85 Jet Change
12.54:1 Compression
2-inch x 30-inch x 3 1/2-inch Hooker Headers
36 Degrees
| RPM |
HP |
Torque |
| 4,000 |
399.8 |
524.9 |
| 4,500 |
466.1 |
544.0 |
| 5,000 |
514.4 |
540.3 |
| 5,500 |
543.2 |
518.7 |
| 6,000 |
552.3 |
483.5 |
| 6,500 |
543.0 |
438.7 |
| 7,000 |
524.6 |
393.6 |
This jet change didn't accomplish much with only a slight gain in horsepower and loss of torque. Total ignition timing is dialed... Total ignition timing is dialed in at 36 degrees BTDC at 2,800 rpm, which is the most timing Marvin is willing to dial into this engine's ignition timing. Marvin has told us time and time again you can push total ignition timing to 38 or 40 degrees. However, there's a stiff price to be paid for pushing total timing beyond 36 degrees BTDC. Marvin is very conservative because what good is an engine scattered all over a racetrack?
We're going to try out the 1,000cfm Holley 4150 (PN 0-80514-1) PC Series carburetor from Performance Carburetors. Although the Holley 0-80514-1 has annular boosters from Holley, Performance Carburetors fits it with down-leg boosters, screw-in air bleeds, high-flow needles and seats, custom billet metering blocks, non-stick gaskets, polished and flowed venturis, float bowl sight plugs, drag float extensions; longer bowl vent tubes, and a special CNC machining technique to perfect the surfaces. Pricing is just under $800 out of the box. For custom tuning to your application, add another $50. Here's what happened on the dyno with our PC Series carburetor. Performance Carburetors PC Series 4150, 1,000cfm
0.93/0.93 Jetting
12.54:1 Compression
2-inch x 30-inch x 3 1/2-inch Hooker Headers
36 Degrees BTDC Total
| RPM |
HP |
Torque |
| 4,000 |
400.2 |
525.4 |
| 4,500 |
467.3 |
545.4 |
| 5,000 |
518.7 |
544.9 |
| 5,500 |
548.9 |
524.2 |
| 6,000 |
554.5 |
485.4 |
| 6,500 |
552.8 |
446.6 |
| 7,000 |
531.6 |
398.8 |
MCE's 427W Raptor is prepared... MCE's 427W Raptor is prepared for Edelbrock's dyno lab by Fred Christian (right) and Ken Van Fleet (left). Tensions run high at a dyno pull, wondering if an engine will measure up to expectations. Marvin predicted 550 horsepower and 550 lb-ft of torque with this road race package based on desktop computations.
We're not going to kid around, this is an all-out road race engine build. The total cost of parts, machining, and assembly put this bad boy just north of $15,000. A street engine would be easier on the wallet. Dyno Pull 4
We've gone back to the Holley 4150 (0-81513-1) carburetor with 0.85/0.85 jetting, which yielded a near-perfect fuel mixture and consistent numbers. Team MCE has chosen to check valve lash in the wake of three pulls to see what it does for performance. Ignition timing remains the same. After three pulls, Team MCE... After three pulls, Team MCE elected to perform a valve adjustment, which gained nearly 10 horsepower at 6,500 rpm.
0.85/0.85 Jetting
12.54:1 Compression
2-inch x 30-inch x 31/2-inch Hooker Headers
36 Degrees BTDC Total Ignition Timing
| RPM |
HP |
Torque |
| 4,000 |
389.7 |
511.7 |
| 4,500 |
460.6 |
537.6 |
| 5,000 |
515.0 |
540.9 |
| 5,500 |
546.9 |
522.3 |
| 6,000 |
561.8 |
491.8 |
| 6,500 |
560.1 |
452.6 |
| 7,000 |
546.2 |
410.2 |
Team MCE gets the 427W Raptor... Team MCE gets the 427W Raptor ready for its first pull. The first pull isn't about power, but reading spark plugs and determining proper jetting. Edelbrock loads the engine at 4,500 rpm for 15 seconds. Then, Team MCE does a spark plug reading and BSFC (brake specific fuel consumption) to determine jet sizing. Sometimes, it isn't the big things you do, but the little things that gain power. When Team MCE performed a valve adjustment, it gained 9.5 horsepower and moved torque higher in the power band-losing torque in the process. Marvin will tell you engine planning and building are a series of trade-offs. If you want more horsepower, you're going to sacrifice some torque. And if you want torque, you're going to give up horsepower at a given rpm. The message here is simple. There are no free lunches in the world of engine building. The 427W Raptor is a racing engine, although you could install it in your Main Street Saturday night cruiser for weekend fun. The catch, of course, is this engine's compression ratio of 12.54:1 along with a 1,000cfm carburetor. Forget pump gas unless you have a buddy who works at the airport or local dragstrip. And if you pump it into a street ride, you're illegal thanks to tough environmental laws.  Benton Jackson of MCE Engines...  Benton Jackson of MCE Engines dials in initial and total ignition timing, which Marvin wanted precisely at 36 degrees BTDC. Marvin's logic is simple. Conditions are different in a dyno cell compared to a road course. It is one thing to flog an engine hard in a dyno cell under controlled conditions and quite another to push it hard racing. A conservative approach to ignition timing will keep an engine in the race.  Holley's Jet Assortment Kit...  Holley's Jet Assortment Kit makes light work of jet swaps and carburetor tuning. We're starting with 0.84 jets primary and secondary for our first full pull based on fuel system specialist Benton Jackson's recommendations.  MCE Engines opted for ceramic-coated...  MCE Engines opted for ceramic-coated Hooker Super Comp long-tube headers with 2-inch primary tubes into 31/2-inch collectors, yielding exceptional scavenging at high rpm.
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