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385-Series Ford Big-Block Build - Monster Mash, Part 2MCE Engines Of Los Angeles Builds Real Power (And Durability!) Into Ford Racing's A460 Race Block From the January, 2011 issue of Modified Mustangs & Fords By Jim Smart Photography by Benton Jackson, Jim Smart
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598ci Big-Block Engine Build, Part 2
Last month, we introduced you to the 598ci T-Rex Ford 385-series big-block from MCE Engines in Los Angeles, California. In truth, we're cheating a little bitbecause it's unfair to call this engine a 385-series 460 Ford big-block. The A460 block is an all-out, super-cube drag racing big-block from Ford Racing Performance Parts. It's not your father's 460 from that old stodgy Lincoln Continental freeway battlewagon. For one thing, you could never infuse 598 ci into a stock 460 block because the stock bore and deck numbers aren't there. This is where the new Ford Racing A460 block comes in to play with its thick webs and decks, siamesed 4.600-inch bores, and 10.322-inch deck. When Marvin McAfee of MCE Engines began planning the T-Rex 598, his goal was to shoehorn as much displacement as he could into this Ford behemoth, while keeping with durability. His logic was pure common sense street smarts-what good is more than 1,000 horsepower if the darned thing blows up? He came up with a near square combination-a 4.600-inch bore and 4.500-inch stroke to achieve 598 ci. Eagle Specialty Products and Mahle Motorsports came up with terrific off-the-shelf components for this effort, and durability comes from making all of your power at the lowest rpm range possible. In other words, Marvin wanted this thing all finished at 6,800 rpm, with peak torque happening between 4,500 and 5,000 rpm, and a redline of 7,200 rpm. McAfee's great success comes from more than a half century of engine building experience. At 77, he knows what works and what doesn't. His success starts with a methodical technique, along with selection of the right parts. Lets get started.  McAfee stresses few things...  McAfee stresses few things are more defeating than a leaker. His strategy is to stagger rear main seal end gaps away from the main cap parting lines. He also uses a thin film of sealer between the seal and main saddle for added assurance. Additionally, he also reminds us to make sure each seal is positioned correctly with lips facing inside. Get this backwards and you can count on having oil on the floor.  Supporting such a huge arm...  Supporting such a huge arm and crank are Clevite 77 main (PN MS-1039V) and rod (PN CB-743VND) bearings, which offer increased durability and improved crush for severe duty operation. McAfee has installed restrictors between the main and cam journals in No. 2 through No. 5 main saddles to reduce flow to the cam bearings and improve main bearing lubrication.  McAfee coated the bearings...  McAfee coated the bearings and journals with his own special assembly lube mix that yields staying power, should an engine wind up sitting for an extended period of time prior to firing up. This is an Eagle 4340 steel crank (PN 44604450002200EGAR100) with 4.500-inch stroke, 3.000-inch mains, and 2.200-inch rod journals, and it weighs roughly 85 pounds. It sports a huge arm (read-huge mechanical advantage), in fact it's the most stroke we've ever rolled into a Ford big-block here at Modified Mustangs & Fords.  Huge 3.000-inch mains sit...  Huge 3.000-inch mains sit on race-ready Clevite 77 bearings. McAfee blueprints each and every bearing for perfect crush and a solid oil wedge. Bearings are installed bone dry, then lubricated between the journal and bearing only to ensure a good wedge on start up...  ...Once McAfee sets the crank,...  ...Once McAfee sets the crank, he checks bearings for solid seating, double-checking his installation work. He gently rolls the crankshaft over and checks feel. Ideally, it should turn with one hand on the snout both before main caps go on and after.  Before the main caps are torqued,...  Before the main caps are torqued, the No. 3 thrust bearing must be centered. McAfee gives each end of the crank a whack with a dead blow mallet (though a brass hammer is being used here), which centers the thrust faces. This ensures uniform journal fit. Choosing The Right Cam For the Job
When we started talking with McAfee about this project back in 2005, his goal was maximum torque rather than horsepower. He ordered a mechanical roller camshaft bent more on torque than horsepower. As time passed and we waited for the A460 block, McAfee started thinking about why horsepower was more important to this project than torque. Torque is a byproduct to an engine this size. Torque is there no matter what you do with horsepower. Earthmoving torque. McAfee had a change of heart with camshaft selection, opting instead for the 34-850-9 mechanical roller camshaft from Comp Cams. Here's how this bumpstick adds up: - RPM Range: 4,400 to 7,200 rpm
- Lobe Centers: 112 Degrees
- Lobe Lift Intake/Exhaust: 0.421/0.420-inch
- Valve Lift Intake/Exhaust: 0.727/0.727-inch
- Duration at 0.050-inch: 275/281
- Duration at 0.020-inch: 308/316
Additional components for the build
- Lifter Set: 836-16
- Push Rods: Manley #1610-16 (3/8-inch w/0.080-inch wall)
- Timing Set: 3122
- Valvesprings: 998-16
- Retainers: 733-16
- Keepers: 611-16
- Lash Caps: 621-16
With this mechanical roller from Comp Cams, peak torque should be somewhere around 4,500-5,000 rpm, handing off to peak horsepower around 6,500-6,800 rpm. Redline, per MCE Engines, is 7,200 rpm. Valve float is likely beyond 7,200 rpm. While retaining the same lobe centers (112), McAfee chose to increase both lift and duration to maximize breathing efficiency at high rpm. It is important to remember that horsepower is a product of not only torque, but rpm. When we increase lift and duration, we enable the engine to ingest a bigger intake charge at high rpm.  Main caps are torqued one...  Main caps are torqued one at a time beginning at No. 5. McAfee's belief is that you should be able to turn a crankshaft with one hand on the snout, whether you have one main cap torqued or all five. Resistance should be uniform. With moly lube on the threads, each main cap is torqued in three increments to 110 ft-lb. The studs should never be bottomed out, but instead, one-quarter to one-half turn from bottoming out. Never use a thread locker because if you ever have to remove the studs, it will be very difficult.  Because this is a drag racing...  Because this is a drag racing engine, Ford Racing thought it appropriate that we use a double-sump, seven-quart drag racing pan for the Fox body Mustang. This pan has reliefs designed to clear the maximum amount of stroke we're using here.  There are also seven-quart...  There are also seven-quart front sump pans available for classic Mustangs and other vintage Fords. McAfee will tell you he's not a gambler. He safety wires the Ford Racing high-volume oil pump (PN M-600-A460) and pick-up bolts like they do in racing and aviation.  Just as important as oil supply...  Just as important as oil supply is oil scavenging. McAfee opens up the drain backs and installs screens to keep unwanted debris from entering the crankcase and pick-up. Plus, a magnetic drain plug is also employed down under.  Earlier, we showed you acceptable...  Earlier, we showed you acceptable resistance to crankshaft rotation. The same is true for camshafts. If it takes more than your hand to turn the camshaft sprocket, bearing clearances are too tight or bearing alignment is off.  Cam and crankshaft endplay...  Cam and crankshaft endplay should be checked during the mock-up phase and during final assembly. Crankshaft and camshaft endplay should be 0.004-0.008-inch.  Mahle Motorsports 4.600-inch...  Mahle Motorsports 4.600-inch forged pistons and low-friction rings get a bath with SAE-30-weight engine oil. The top two ring end gaps are positioned at 180-degree spacing for proper installation. Oil ring end gaps are also 180 degrees opposite at the wristpin.  In any case, always follow...  In any case, always follow the manufacturer's directions for best results. McAfee had to dig out his largest ring compressor, one he hadn't used in years, because MCE doesn't build them this big that often.  These 18-bolt Ford Racing...  These 18-bolt Ford Racing C460 race heads call for special prep work, and Manley stainless steel valves the size of cocktail tables, to control traffic through Holland Tunnel-sized intake and exhaust ports. PowerHeads of Wildomar, California, cleaned these castings up with a port match for improved flow.  However, no specialized port...  However, no specialized port work was done as we wanted to know what these heads did out of the box. Installed valvespring height is 1.900-inches. Seat pressure, valves closed, should be 228 pounds at 1.900-inches. Open pressure should be 702 pounds at 1.200-inches, with spring coil bind at 1.090-inches.  MCE uses non-petroleum-based...  MCE uses non-petroleum-based solvents in the final clean-up work. Acetone is probably your best bet and certainly safer than M.E.K. (Methyl Ethyl Ketone).  Contact surfaces are wiped...  Contact surfaces are wiped down with a lint-free tack rag and Acetone. Even skin oil is bad for these surfaces because any oil disturbs sealing and acts as a lubricant making a compression or coolant leak more probable.  This is a special 18-hole...  This is a special 18-hole Fel-Pro cylinder head gasket (PN 1092) designed specifically for the A460 block and C460 cylinder heads. It consists of a metal sandwich and self-sealing material. Fire rings must be cleaned thoroughly with Acetone or M.E.K. to remove the coating (sealer) before installation.  ARP cylinder head studs are...  ARP cylinder head studs are turned until they touch bottom, then backed out one-quarter to one-half turn. High temperature anti-seize has been used on the stud threads. The center ten 1/2-inch head studs are torqued first in three increments to 100 ft-lb, then both sets of 7/16-inch outer bolts and studs to 60-65 ft-lb.  You're going to need a crow's...  You're going to need a crow's foot for the outboard 7/16-inch studs as shown. Inside the valley are four more 7/16-inch bolts that call for a short socket.  You will literally have to...  You will literally have to take an 11/16-inch 3/8-inch drive socket and cut it down to size to fit these bolts.  McAfee has opted for an aggressive...  McAfee has opted for an aggressive mechanical roller camshaft, which gets these linked roller tappets (PN 836-16). Each set gets a generous dressing of MCE engine assembly lube after soaking in 30-weight engine oil for 24 hours. McAfee prefers a good oil prime in and between moving parts on start up. The bar gets located toward the valley center, never toward the block.  When we contacted Jesel Valvetrain...  When we contacted Jesel Valvetrain Innovation, it was happy to work with us on getting a race-ready precision Mohawk (KPS11057) valvetrain going, because stud-mounted rockers just weren't going to cut it.  Here, McAfee lays down the...  Here, McAfee lays down the Jesel rocker stand and torques the large fasteners to 60-65 ft-lb, and small ones to 26-28 ft-lb.  Jesel rocker shafts are torqued...  Jesel rocker shafts are torqued evenly to 22-25 ft-lb, and feature a 1.8:1 ratio. Pushrods measure 10.0-inch x 3/8-inch with a 0.080-inch wall thickness.  Valve lash is adjusted by...  Valve lash is adjusted by taking the crankshaft in 90-degree increments with the engine's firing order. McAfee has marked the balancer at TDC/Zero, 90, 180, and 270 degrees. Although cam manufacturers tend to specify valve lash hot, you've got to start somewhere cold. Marvin allows for 0.004-inch growth from engine heat. He sets the intake/exhaust lash at TDC compression stroke for each bore. Intake lash is 0.024-inch cold or 0.028-inch hot. Exhaust is 0.026-inch cold and 0.030-inch hot. A feeler gauge should present some resistance to movement, but not too tight. After the engine is run in, precise hot valve lash is checked before cool down.  Ford Racing offers the necessary...  Ford Racing offers the necessary intake gasket (PN M-5439-G460), which is a unique intake gasket for the C460 raised-port heads.  McAfee examines port match...  McAfee examines port match and gasket alignment with a flashlight.  Custom Performance Racing...  Custom Performance Racing in Gardena, California, is fabricating long-tube step headers for the T-Rex. We'll go deeper into header design and how it affects power when we go to the dyno. Next time, we're going to wrap up the T-Rex 598 with closing thoughts, finishing touches, and a trip to the dyno room to learn something about both horsepower and durability.
 | MCE Engines' T-Rex 598 Is A Brute 800-Horsepower, 1,320-Foot Performer |
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