MCE Engines Builds A 427ci Ford Engine - Eight Barrels-No Waiting
MCE Engines Builds a 427-Inch, 600-Horse Street Screamer
From the March, 2007 issue of Modified Mustangs & Fords
By Jim Smart
Photography by Benton Jackson, Jim Smart
Special Thanks to Marvin McAfee, from MCE Engine, for his technical expertise and knowhow.
When Blair Jennings of Santa Barbara, California, called Marvin McAfee at MCE Engines in Los Angeles, his voice and story were familiar. Blair's father, Allan, who passed away many years ago, once collaborated with Marvin on his engines. They enjoyed a terrific friendship and working relationship centered on fast cars and the scream of high-performance Ford engines. When George Folmer, Parnelli Jones, and Dan Gurney were cutting apexes in SCCA Trans Am competition approaching 40 years ago, Marvin was building competition engines for people like Blair's father-and Blair was there to witness it all through the eyes of a child. After losing track of Marvin for the better part of a lifetime, Blair rediscovered him through a recent story in Mustang & Fords.
At his Santa Barbara shop, Blair had a 427W stroker all in pieces for his '66 Mustang Street Trans Am car that was under construction. He didn't know where to turn for engine-building expertise until he read about MCE Engines in our magazine. That's when he called Marvin for a long-overdue hello. Stunned by a call from someone he hadn't seen in 36 years, Marvin was eager to shake Blair's hand. He was also saddened by the loss of Blair's father and a friendship that quietly slipped away over time. Inspired by that friendship, Marvin did something he and the MCE team don't normally do. He chose to build Blair's engine using parts MCE Engines didn't specify to begin with. MCE Engines has a house rule: All parts must be MCE approved. Blair was the rare exception. Because he and his father were treasured friends, Marvin broke his own rules and worked with what the younger Jennings brought him.
Blair wanted what was almost impossible to achieve-an all-out racing engine with good street manners. We're talking Webers, a radical cam-shaft, big Edelbrock Victor heads, and a dry-sump oiling system. Marvin and the MCE team felt like Blair might be off his rocker. They took his dreamy-eyed idea and looked at what could be done with it.
Formula For Big-Inch Success
Blair did the right thing when he ordered his 427W stroker kit, opting for a Probe Industries 4340 super-strong steel crank, H-beam rods, and forged SRS flat-top pistons. Edelbrock Victor heads were an excellent choice for Blair's 427W, yielding 2.08/1.60-inch valves, large ports, and 62cc chambers designed for better quench, i.e., rapid flame travel across the top of the piston.
Blair dreamed of having Weber carburetion-something his Bow-Tie buddies did not have. But Weber carburetors are not easy to own and maintain. They look terrific, and under ideal circumstances they perform extremely well. Webers are as close to fuel injection as you can get with a carburetor. Marvin's concern was the minimal clearance Blair's Webers would have beneath his Mustang's cowl-induction hood. It wasn't just a performance issue, but a safety one as well. Because fuel vapors, called "stand off," tend to form immediately above each carburetor at high rpm, the risk of ignition in a confined area is what concerned Marvin most. He knew from years of experience that Blair needed a lot of room above his Webers. This remained a challenge for Blair as of press time.
This late-model 351W two-bolt...
This late-model 351W two-bolt main block has been girdled with a windage tray. It also has a one-piece rear main seal. Marvin blueprinted it to MCE standards, working oil passages and installing restrictor plugs at No. 2 through No. 5 main journals to improve oil distribution. He also notched cylinder walls and pan rails to clear rod bolts, and thoroughly inspected for cracks and other abnormalities. The No. 1 main journal does not get a restrictor plug. As you can see, the craftsmanship is impeccable. Marvin uses Glyptal coating from The Eastwood Company to seal unmachined iron surfaces.
Blair ordered a complete 427W...
Blair ordered a complete 427W stroker kit from Coast High Performance. We like the 4340 steel crank, H-beam rods, and forged 4.030-inch SRS flat-top pistons. Probe increases stroke to 4.170 inches to achieve 427 ci. Rod length center to center, is 6.200 inches, yielding a rod ratio of 1.48:1. Marvin has massaged this crank to MCE specs, micro-polishing the journals for better oil control, chamfering the oil passages for improved flow, with a precision balance job from both MCE Engines and Automotive Balancing.
At first glance, these don't...
At first glance, these don't look like Edelbrock Victor heads. They have been Marvin-ized with port work, precision fitment, Glyptal coating, and MCE's own black enamel. High-swirl 62cc chambers improve quench.
Formula For Big-Inch Success (Cont'd)
Note how Edelbrock puts the...
Note how Edelbrock puts the spark-plug firing tip deep into the chamber. Examine the chamber's edges closely. Marvin removed all sharp edges, which reduces the risk of detonation and hot spots.
This isn't the cam Marvin...
This isn't the cam Marvin had in mind for this application. Blair brought him a Schneider Racing hydraulic roller cam, grind number 284-RH. What this means in actual numbers is 284/284 running duration, a lobe lift of .340/.340 inch, and valve lift of .544/.544 inch with lobe centers at 112 degrees. This is an aggressive camshaft designed to do its best work at 3,500-5,000 rpm, where peak torque is expected to occur. While this makes sense on a racetrack, it doesn't hold much weight on the street. Idle quality and driveability will be compromised. At high rpm, get out of the way!
High-performance engines need...
High-performance engines need hot ignition systems and healthy charging systems to keep a battery ready. Race-proven MSD systems, especially when enhanced with the 6AL box, light a volatile mixture under the toughest circumstances. Powermaster's 120-amp single-wire alternator not only keeps a high-energy ignition system fed, but also all those power accessories Blair may be thinking of installing. Old-fashioned 45-, 55-, and 65-amp externally regulated alternators just don't cut it when you're running a high-amp sound system and power windows.
As mentioned earlier, Blair...
As mentioned earlier, Blair opted for Weber induction available from Inglese. These are 48mm throttle bores, which flow 635 cfm each for a total of 2,540 cfm. This level of carburetion is more attuned to the racetrack than street. "I would never recommend these 48mm throttle bores for street use," Marvin says. Webers must be synchronized using a unison, which measures manifold vacuum. This gets all eight carburetors to exactly the same idle mixture. When you run Webers, you must think of your V-8 engine as eight individual engines sharing four float bowls.
California Pony Cars set us...
California Pony Cars set us up with a cast-aluminum timing cover, which has been blueprinted to MCE specs. (Blueprinting means going over the top with your engine build.) Marvin radiused all of the passages for smooth coolant flow and oil return. Blair brought Marvin this Edelbrock water pump, which was also blueprinted to MCE specs. Marvin got rid of the edges to improve coolant flow and to minimize fluid turbulence.
This is a Weaver Brothers...
This is a Weaver Brothers dry-sump oiling system. It consists of a three-stage pump, hoses, and a custom-made Canton dry-sump pan, which we will discuss later. What makes this oiling system different than your Mustang's is its dry-sump design. Dry-sump oiling ensures positive oil supply under just about any condition imaginable. It provides oil from an oil tank, and it scavenges the return oil for constant uninterrupted flow.
Race Attitude - Street Demeanor
When Blair brought his 427W to MCE Engines, he learned quickly he made the same mistake as a lot of us: He didn't properly plan his engine project, and he ordered parts that don't always work well together.
Blair wanted the awesome look of Weber carburetors, but he didn't consider the sacrifices that must be made to have them. He opted for a radical high-rpm roller camshaft without considering what he would be giving up on the street. Blair chose the Edelbrock Victor cylinder head, which is an excellent head for high-displacement 351 Windsor strokers. Even at low rpm, the Victor works well when you're huffing lots of displacement. Victors were a good choice.
Marvin scolded Blair for his part selection, pointing out that too many of us package big-inch small-blocks like they're still small-blocks. Martin stressed that when you stroke a 351ci small-block to 427 ci, you no longer have a small-block, displacement-wise. You have a big-block, with much greater displacement and power than you had at 351 ci. That means you must feed the hungry small-block like a big-block with larger fuel lines, bigger ports and runners, a larger carburetor or throttle body, and so on. You also need to have a driveline that will stand up to the horsepower and torque a big-block makes. When you increase displacement, you must raise the bar in every way.
Although dynamic balancing is optional (extra cost) with all engine builders, it is a necessity to engine smoothness and longevity. It is manda-tory at MCE Engines, but Marvin takes it a step further with his own disciplined approach to dynamic balancing. He weighs everything before it goes to Automotive Balancing, then AB precision balances everything to Marvin's own specs.
Dynamic balancing happens for the same reason we balance tires-to remove shake and vibration. Centrifugal force is an ugly thing when spinning and reciprocating parts are not in perfect balance. All pistons, rings, and bearings must weigh the same. Engine oil must also figure into this equation. Pistons and rings must weigh exactly the same as crankshaft counterweights. They should dance around each other smoothly, with the precision of a Swiss watch.
With dynamic balancing, each piston is machined down to the same weight as the lightest piston. Rings and pistons are weighed together as individual assemblies. All rods must weigh the same as the lightest one. To get it all in balance, remove metal from the heavier parts to get them down to the same weight as the lightest part. The same can be said for the crankshaft.
Internally balanced engines can be balanced independently of the harmonic balancer and flywheel/flexplate. Externally balanced engines, like the small-block Ford and FE-Series 428 Cobra Jet big-block, call for including the harmonic balancer and flywheel/flexplate in the balancing process.
Assembly begins with cleaning...
Assembly begins with cleaning everything. Marvin works the oil galleys with lots of soap, water, and brushes. He uses rifle-cleaning brushes to make sure every trace of dirt and iron particles are gone. He also visually inspects everything closely. Does the passage look clean to your naked eye? Can you see all of the passage?
Because Blair is running a...
Because Blair is running a large-radius 4340 steel crank, it's necessary to use H-Series Clevite main and rod bearings. Notice Marvin has opened up the oil-galley passages to improve oil flow. Remember, crankshaft journals roll on a solid cushion of pressurized engine oil. Oil isn't just a lubricant; it is a coolant as well. He wants clearances that aren't too tight, which would restrict oil flow. The right measure of clearance and oil flow carries heat away from the bearings.
Once Marvin properly seats...
Once Marvin properly seats the main bearing halves in the block saddles, he gives them a dressing of his own assembly lube. Never use too much. Marvin supports doing a pressure prelube on your engine before firing to ensure plenty of lubrication at the bearings and on all moving parts.
Late-model small-block Fords...
Late-model small-block Fords utilize a one-piece rear main seal common from 1985-up. Although Fel-Pro doesn't suggest using a sealant around the circumference of this seal, Marvin recommends it. He runs a thin film of high-temp RTV silicone around the outside to ensure proper sealing.
With the mains lubed, Marvin...
With the mains lubed, Marvin is good to go with crank installation. He thoroughly checks main journal clearances, keeping them around .00220 inch with an average of .00224 inch. Rod bearing clearances run about the same at .0021 to .0022 inch, averaging .00218 inch. Endplay is .005 inch.
Before Marvin sets the main...
Before Marvin sets the main caps, he applies high-temp RTV silicone sealer between the No. 5 rear main cap index and block for additional sealing. This reduces the chance of engine oil leaking between the main cap and block.
Marvin torques main caps in...
Marvin torques main caps in third values. Accepting torque value is 60-70 ft-lb, which means he torques these bolts to 23 ft-lb, then 46 ft-lb, then a full 70 ft-lb. With each torque, he checks the crankshaft for freedom of rotation. You should be able to turn the crank with your fingertips or the weight of a breaker bar. Threads should always be lubricated and free of damage for accurate torque readings.
With No. 3 main cap snugged...
With No. 3 main cap snugged (not torqued), Marvin whacks the rearend of the crank with a mallet to help align and center the main thrust bearing. Then he checks endplay, which should be .004-.008 inch depending on how you intend to use the engine. Maximum allowable endplay is .012 inch.
Piston-ring design and installation...
Piston-ring design and installation is a fascinating study in cylinder sealing and oil control. Although most people call the top two rings "compression" rings, only the top ring handles compression. The second ring is an oil-control ring designed to meter oil up the cylinder wall. The bottom pair of oil rings are actually oil wipers, which carry excessive oil off cylinder walls on the downstroke.
These are oil-wiper rings...
These are oil-wiper rings supported by a ring expander. It is important to ensure proper expander installation at this juncture. Expander ends need to lock as shown. Overlap them and you can expect trouble almost immediately.
Piston-ring end gaps must...
Piston-ring end gaps must be located initially at 45-degree intervals-9, 12, 3, and 6 o'clock. Ring end gaps should be checked on all eight cylinders prior to installation and at three positions-top, middle, and bottom. Another important issue is piston-ring side clearances; you need .002 inch on the top and second rings. This ensures proper oil control behind the ring for better sealing.
Pay close attention to piston...
Pay close attention to piston pin clips in bushed pin installations. Roll-in clips, which are designed to protect cylinder walls, are commonplace these days. These are conventional C-clips, which require close attention during installation. Marvin blueprints each C-clip by working sharp edges and ensuring each clip is firmly seated.
Marvin knows he'll get a lot...
Marvin knows he'll get a lot of arguments, but he never rolls piston rings into the grooves during installation. He uses a piston ring expander as shown to install rings. Rolling rings into the grooves will distort them, which creates potential for improper ring seating and sealing.
Did you know small-block Ford...
Did you know small-block Ford cam thrust plates install properly only one way? And did you know the 351C, 351M, and 400M take a different cam thrust plate than 221-351W? We have found 351C cam thrust plates installed on 289/302/351W engines, and we have seen them installed backwards. When you install this cam thrust plate backwards, you're robbing the cam sprocket of important lubrication even though return oil lubricates. The slot gets oil from the galley to the cam sprocket. When installing this cam thrust plate, use a thread locker and torque the bolts to 9-12 ft-lb. Do not overtorque.
Delivery day early in 2006:...
Delivery day early in 2006: from left to right are Marvin McAfee, Blair Jennings, and Benton Jackson. Blair hauled this 600-horse 427W home to Santa Barbara. Expect to see his '66 Mustang fastback in Mustang & Fords in the future.
When Blair brought Marvin his 427W in a basket, he also brought an aggressive hydraulic-roller race cam from Schneider Racing Cams. This is an off-the-shelf bumpstick ready for racing. Blair wants to use his '66 Mustang fastback on the street as well as the track, though. Here are his cam specs:
|Schneider Racing Cams Grind No. 284-RH|
|Running Duration:||284/284 degrees|
|Lobe Centers:||112 degrees|
|Lobe Lift:||.340/.340 inch|
|Valve Lift:||.544/.544 inch|
|Peak Torque:||3,500-5,000 rpm|
|Specifications At .050-inch tappet height|
|Intake Open:||2 degrees BTDC|
|Intake Closed:||42 degrees ABDC|
|Intake Centerline:||110 degrees ATDC|
|Exhaust Open:||46 degrees BBDC|
|Exhaust Closed:||-2 degrees BTDC|
|Exhaust Centerline:||114 degrees BTDC|
|Duration at.050 inch:||224/224 degrees|
|Cam installed 2 1/2 degrees retarded (to enhance horsepower)|
Duration and lift will prove the most challenging for Blair. When you're shopping for a cam, duration, lift, and lobe centers are the main concern. A lobe center of 112 degrees isn't the issue here-duration and lift are. Because duration is 284/284, which is rather lengthy, this will affect both idle quality and manifold vacuum. The same can be said for valve lift, which also robs vacuum and idle quality. Duration has a direct bearing on valve overlap (the period when both valves are off their seats). Overlap helps power on the high end, but hurts idle and manifold vacuum down low. These elements are what will make Blair's Mustang restomod a chore to drive on the street, yet incredible when it's time to go road racing. Our message here is simple: You cannot have both superior street and race qualities in the same engine.
What Is a Dry-Sump Oiling System?
This is what a typical dry-sump...
This is what a typical dry-sump oiling system looks like. Shown here is a three-stage pump (actually three pumps-one for pressure and two for scavenging). You can have as many stages as you want, depending on how much scavenging you need. Generally, there is one stage for pressure and at least one stage for scavenging. In this application, we have one pressure stage (capped) and two scavenging stages. The scavenge ratio is 4:1, which means it has the capacity to return way more oil than it receives. This means more power because an efficient scavenging system will reduce crankcase pressure.
A dry-sump oiling system does away with your engine's conventional oil pan and internal pump, replacing them with a beltdriven external pump system and low-profile oil pan. Dry-sump oiling systems are designed specifically for racing even though they may be used in street applications. They are used in racing to ensure a constant supply of oil under high lateral g-forces and hard acceleration, which is crucial to engine survival at high rpm.
Because racing engines demand a continuous supply of oil under pressure at high rpm, a dry-sump system is designed to keep them well supplied. Conventional wet-sump oiling systems can develop oil supply problems at high revs, cavitating the oil pump and causing an oiling system to areate (suck air), causing major engine damage in nanoseconds. At high rpm, an engine's internal oil pump can empty a deep-sump racing oil pan, rendering moving parts dry in short order. At high rpm, all of the pan's oil winds up at the top of the engine, filling valve covers and the lifter valley completely-robbing important moving parts of pressurized lubrication. The dry-sump oiling system gives us more control of where the oil is. A dry sump gets oil back to the reservoir (oil tank) as quickly as it leaves.
A dry-sump oiling system consists of an external multistage, a beltdriven pump, cog-belt drive pulleys, high-pressure hoses and fittings, and a special dry-sump oil pan. The pan is designed to channel oil back to the pump and reservoir. When we speak of pump stages, we're talking individual pumps (stages) designed to move oil. Typically, there is one pump to provide oil under pressure to give us an oil wedge between moving parts. Then, we have at least one scavenge pump stage to collect oil and return it quickly to a reservoir. We can scavenge oil where a deep sump pan would normally be. We may also scavenge oil at the lifter valley and even high up at the valve covers. Much depends on the kind of driving we're going to be doing.
Reunited and It Feels So Good
Here is Blair Jennings at...
Here is Blair Jennings at an SCCA Trans Am race at Riverside, California in 1970. That's the Grabber Blue Boss 302 campaigned by Jefferson Enterprises, powered by an MCE-built Boss 302.
Blair met Marvin long ago when he was in adolescence. At the time, Marvin was building race-winning Boss 302 engines for SCCA Trans-Am competi-tion. The Grabber Blue '70 Boss 302 Mustang campaigned by Jefferson Enterprises went after big game with a Boss 302 engine built by Marvin's Competition Engines (MCE). Blair's father looked to Marvin for his expertise-and he got it, using powerful small-blocks from MCE Engines.
As the fever of intense Trans-Am competition faded and faces changed, Marvin moved on, and so did Blair and his father. It would be more than 30 years before Marvin and Blair saw one another again. More than a year ago, Blair brought his engine to Marvin for a second generation of Jennings engines built by Marvin's Competition Engines.