Michael Johnson
Technical Editor
February 3, 2014

Horse Sense: Centerforce says the definition of DYAD is "two units treated as one; a couple; a pair, or combining power of two."

After owning one of the first Coyote swap cars on the planet for a couple years, it was time for a new project car. I became intrigued by the ’01 Bullitt model, and after just missing out on a Highland Green version (I really wanted that one), I found a black example that fit perfectly into my budget.

Going from my Coyote-swap ’94 Cobra to a stock-engined ’01 Bullitt was quite the step down in power. However, the Bullitt was a much nicer starting point than the Cobra. The Bullitt was the perfect cruising Mustang. It was slow, which kept me out of trouble, it handled amazingly well thanks to a Maximum Motorsports Grip Box suspension, had amazing brakes thanks to a Brembo package up front, and most importantly, it was stock and reliable.

Even with all that, as I mention, it was slow. I mean, dog slow. But that was OK for a little while because we... had... a...plan. It probably only felt really slow because the Coyote Cobra made 400-rwhp with a 7,000 rpm shift point. The Bullitt’s little 4.6 Two-Valve couldn’t even come close to those numbers. Something had to be done, but what were our choices?

When Ford Racing announced its new 5.0-liter short-block, we jumped at the chance to get one under the Bullitt’s hood. But what would we pair with the short-block? We toyed with the idea of doing a Four-Valve head conversion, but wanting to avoid complications, we opted out of that and decided to use a Two-Valve loaded with the best parts available. As such, we went to Trick Flow for one of its top-end kits.

Our goal was to prove a point—that a Two-Valve could be a viable option. We wanted to make, as KJ would say, big steam with a and show you didn’t need a Coyote swap to make real N/A power.

Were we able to prove our point? You’ll have to read on to find out.

1. We were chastised on Facebook for running through a parts store having a sale on silver paint, but trust us, when you see the finished installed shot, you won’t see all silver. However, this is how the 5.0-liter stroker looked just prior to throwing it on the trailer, and hauling it up to David Piercey’s Mustang Performance a few miles north of our Tampa, Florida, office. Dave (D2) Squire and I assembled the top end of the engine here at the Tampa office before taking it up to Dave (D1) Piercey’s shop. Here you can see we’ve added the Trick Flow Track Heat heads (TFS-51910004-M44; $1,149.97 per) and Street Burner intake (TFS-51800000; $869.97) to Ford Racing’s new 5.0-liter modular short-block (M-6009-A46X; $5,299). Instead of reusing the factory cam covers, we used Trick Flow items there as well. For headers, you can see we went with BBK Performance’s 15⁄8-inch long-tube headers (15410; $599.99), while a Trick Flow 75mm throttle body (TFS-24075; $189.97) sits up top. We hadn’t received the new PA Performance alternator bracket as part of it, and as you'll see, the bracket flips the alternator around at the front of the engine. Before tackling something like this on your own, it's a great idea to have installation instructions not only from Trick Flow, but also Ford, to make sure you don't miss or mess up any steps. You don't want to wipe out an engine because you missed a step, torque sequence, or the like.

2. This is what we started with, Ford Racing’s M-6009-A46X 5.0-liter short-block. Ford Racing uses an ’05-’10 aluminum block with a 3.572-inch bore and an Eagle 3.75-inch forged stroker crank to arrive at 5.0 liters of displacement. This short-block also features Eagle H-beam connecting rods with ARP 2000 bolts, Mahle forged aluminum pistons, and a high-pressure oil pump. The rotating assembly is neutral-balanced, and the short-block is ready for your top end, whether it be a Two-, Three-, or Four-Valve combination. Ford Racing dyno’d several different combinations with this short-block, including a Three-Valve combo with an FRPP 2.3 supercharger and Hot Rod cams, and it made 748 horsepower and 667 lb-ft of torque at the flywheel. The dyno number we were more interested in is the one featuring the parts we used for this bolt-on experiment. Those numbers were 424 horsepower and 416 lb-ft of torque at the flywheel. The compression ratio for the engine Ford Racing tested is 10.78:1, and we used the exact same parts so our engine's compression ratio should be in that neighborhood, as well.

3. Trick Flow’s Twisted Wedge Track Heat 185 cylinder heads for Ford’s 4.6/5.4 modular are designed to go right in place of factory Two-Valve heads. Since the Trick Flow heads are the only aftermarket choice, they’re pretty much the only game in town, and we’ve seen them used on both fast street cars and racecars alike. Since we wanted more performance than could be offered with PI castings, we chose the Trick Flow Twisted Wedge Track Heat 185 heads. These heads feature a CNC-machined, 44cc combustion chamber volume, 1.84/1.45 valves, a 185cc intake runner volume, and a 93cc exhaust runner volume. They arrived to us fully assembled with valves, beehive-style springs, 7-degree locks, powdered-metal valveguides, and a three-angle valve job.

4. Before installing the heads, you have to decide the heads’ orientation. In other words, figure out which side each head will be installed on. The heads aren’t side-specific until you add the oil plugs. These plugs are critical for oil flow and pressure through the heads, and must be installed, or you’ll have oil leaks, and the valvetrain won’t receive proper oiling. It’s way easier to install these plugs into the heads while they’re off the engine.

5. Keeping in mind the cylinder heads’ orientation, we installed the heads on top of the Ford Racing head-changing kit’s MLS head gaskets. Like the heads, the head gaskets are side-specific. Since we were starting fresh with a new engine, we didn’t need them, but Trick Flow includes rubber sleeves to help place the head bolts on the heads when installing them with the engine in the car. There’s a specific torque sequence for the heads, which is covered by the Trick Flow instructions.

6. Ah, yes, we wanted the mean sound that comes with adding rowdy cams. Since we were adding the Trick Flow heads, we thought the perfect match for them would be Trick Flow’s Track Max hydraulic-roller cams for 4.6/5.4 Two-Valve engines ($569.97). These 0.550-inch-lift cams have a basic operating range of 1,500-to-5,000 rpm with a 228 intake/230 exhaust duration at 0.050-inch lift and a 112-degree lobe separation. All of the above help to maintain everyday driveability and stock-computer compatibility. These cams work with both stock PI heads, and of course, Trick Flow heads. They made our Bullitt sound unlike any other Two-Valve. It’s worth adding these cams to a stock engine just for the sound alone.

7. Installing the cams is pretty straightforward. The cam caps must be removed; on the Trick Flow heads, they’re numbered. Make sure to reinstall the caps in their proper place. Using a liberal amount of cam lube, we place the cams onto the heads and reinstall the caps. The caps also have a specific torque sequence, and the instructions will spell that out for you in an easily understood manner.

8. We’re going to move to the bottom of the engine for a little bit to install the oil pickup tube. The Ford Racing short-block comes with an installed windage tray, and you’ll have to loosen the tray slightly to slide the pickup tube into place. If you do the same as we did with a Ford Racing short-block, it comes with a new oil pump but doesn’t include an oil pickup tube, so keep that in mind. If you order a new oil pump from Ford Racing, it comes with the pickup tube.

9. Our Bullitt had received a new BBK Performance X-shape crossover pipe a few issues back, but it still had the stock exhaust manifolds. There’s no way we were going to use those for the 5.0-liter stroker, so we got a pair of BBK Performance’s 15⁄8-inch, full-length headers ($599.99) to help the 5.0-liter stroker exhale as easily as possible. We chose the ceramic finish since we want them to last. These headers also feature a 3⁄8-inch-thick flange and a two-bolt flange collector to line up with a BBK Performance 21⁄2-inch, X-shape crossover pipe designed for the full-length headers that we’re also adding this time around.

10. We’d say things are getting pretty serious now. We’ve installed the timing chains and guides, crank and cam sprockets, and the timing chain tensioners. The Trick Flow top-end package comes with a timing chain installation kit so you won’t need to get one from Ford Racing. We had both a Trick Flow, and a Ford Racing timing chain package, but the most important piece of the puzzle in front of you is the TDC tool on the crankshaft snout. That has to be lined up with the dowel on the block as you see it, or some people just position the crankshaft keyway at 11 o’clock, and let ’er eat. We didn’t want to go that route so we borrowed the tool from Sam Lippincott at Coastal Chassis in Tampa. There are timing marks on the crank sprocket, and on the cam sprockets. Likewise, there are links on the chain just like on a bicycle chain, and after you line up the cam sprockets (driver-side sprocket at 12-to-1 o’clock, passenger-side cam sprocket at 11 o’clock), align the timing marks on the sprockets with the darkened links on the chains, and you're set. Then release the pin from the tensioners, and timing chain installation is done.

11. Here’s a close-up shot of the timing chain tensioner. These tensioners keep tension on the timing chain guides, which in turn keep tension on the timing chains. Do not pull the pin on the tensioners until you know for sure everything is installed correctly.

12. Now we can install the lash adjusters (lifters) and the cam followers (rockers). Again using engine lube, we coat the lash adjusters, which we also soaked in oil, before installing the cam followers. Using engine lube will help with the installation of the cam followers.

13. Trick Flow includes a cam follower installation tool, and the instructions also detail how to install them. Basically the tool allows you to compress the valvespring on each individual intake or exhaust cylinder so you’re able to install each follower. The critical part is making sure you don’t lose any valve-stem keepers when compressing the valvesprings. Pay attention and make sure the valve stem is going down along with the valvespring. It will help to have a buddy or two assisting and watching during this part of the build.

14. Now we can prep the long-block for installing the front cover. Notice we’ve already installed the crank trigger wheel, or crankshaft sensor ring, from the timing chain kit. Dabs of silicone must be placed where the heads meet the block and where the block meets the oil pan. Then the front cover can be installed onto the long-block. One thing to note, we used a ‘99-’04 front cover. As we mentioned earlier in this report, Ford Racing uses a ’05-’10 block as the basis for the 5.0-liter modular short-block, and one of the bolts on the cover doesn’t match up to the engine. Some people drill and tap that hole on the engine, but that was too risky for us. We chose, instead, to silicone the hole on the cover, and we are happy to report no leaks. We had to source front-cover hardware from Brandon Ford, as well, since we were building a new engine, and didn’t have access to the old engine’s front cover bolts at the time.

15. Moving back up top, we added a new water tube to the engine. Trick Flow includes a rubber hose for this, but we felt better having a metal tube. It’s available through Ford, so you can go this route, as well. The tube installs at the front of the valley and bolts onto the head at the back of the engine. Notice we’ve also installed the engine’s intake gaskets in place.

16. Before installing the intake on the engine, however, the lower intake must be pre-assembled. Dave (D2) uses the Trick Flow-supplied hardware and gaskets to assemble the lower prior to bolting it onto the engine. There are torque sequences and specs one must follow with the majority of the engine, including the Trick Flow lower, so make sure to have them handy and follow them.

17. With the intake assembled, D2 sets it in place on the long-block. We also added Trick Flow cam covers to the mix, as well. This is where we started hearing taunts of silver paint sales at the local auto parts store, but as you’ll see, it all turns out nice in the end. Like everything else, follow the torque sequence and specs on the intake as they are specific.

18. With the lower intake installed, D2 installs the upper intake. We’ve already installed the Trick Flow 75mm throttle body onto the upper, along with the intake port fittings into the upper intake manifold. These fittings need Teflon sealer before installing them into place. The lower fitting is for the engine’s PCV system. We would take the upper manifold off just before engine installation into the car, but we were just getting the engine ready for a pretty shot at this time.

19. Next up we oil the tips of our Ford Racing fuel injectors and install them into place. We chose to go with Ford Racing’s 47-lb/hr injectors. Yes, they’re a bit overkill (OK, a lot overkill), but they worked just fine, and tuner James Gordon from Tuning by James is familiar with their tuning parameters.

20. Once D2 and I were done assembling the top end of the engine, we took the car and the engine up to David Piercey’s Mustang Performance just north of Tampa, Florida, to install the new engine. Dave Piercey’s (D1) idea was to drop the engine out from the bottom, leave the K-member in the same spot, install everything onto the new engine, place it right back onto the K-member, and lower the car down onto the new engine. We made sure to mark where the K-member was on the shop floor in case anything moved, but we had no such issues.

21. Of course, a new engine needs new plugs. We chose Motorcraft items, going with Trick Flow- recommended SP-432 plugs. D1 arranged a “clean table” for new or clean parts so we would know what was left to install. Keeping track of new or clean parts makes it easier to track your progress, as well as identify what you may need to finish the job.

22. If you caught our Bullitt’s exhaust install in the Jan. ’13 issue (pg. 96), you’ll know our tuner James Gordon noted our Bullitt’s alternator giving up the ghost in the upper rpm range. We didn’t want that to happen with the new engine so we called up PA Performance for an 130-amp, 4G unit ($289), along with the company’s Power Pack kit. PA sent the Power Pack kit just in case we were still short of voltage once everything was installed. However, when all was said and done, the 130-amp 4G alternator was just what the doctor ordered to cure our upper- rpm voltage issues.

23. Once everything was at Mustang Performance (D1’s shop), we had to transfer the wiring from the old engine to our new 5.0-liter stroker engine. Here D1 (left) and D2 (right) are transferring the old engine’s harness to the new engine.

24. For a clutch, we chose to go with Centerforce’s DYAD dual disc set-up ($1,495). Like the fuel injectors, this clutch is probably way too much for this engine’s power output, but there are certain things you only want to do once, and a clutch is one of those items. The DYAD clutch is capable of handling way more power thanks to its floating, dual-disc design. There was increased pedal effort, and the clutch is unlike any stock clutch we’ve used, but the DYAD clutch brings promises of greater longevity and quiet operation—and should a power adder ever find its way onto the engine, we won’t have to swap out the clutch.

25. As you can see, D1 has installed the flywheel, the drive disc, the floater, and the floating disc. Even though it looks intimidating, installing the DYAD is straightforward and easy. You’ll spend more time admiring the clutch than actually installing it.

26. The moment of truth. D1 and D2 move the 5.0-liter stroker engine into place with the transmission installed onto the engine. We drop the engine onto the Bullitt’s Maximum Motorsports K-member, get the engine hoist out of the way, and drop the car down on the new combination.

27. D1 finishes up the clutch by installing the clutch cover, and following the torque specs, and sequence. And yes, we had to remove the passenger-side header in order to mate the transmission with the engine and make it easier to install the starter. Notice the header gaskets on the ground, too. We chose to use factory gaskets for the BBK headers.

28. With the engine installed in the car, we raised it up to do the exhaust, which consisted of installing the BBK Performance X-shape crossover pipe ($179), and connecting it to the car’s existing Flowmaster after-cat exhaust. Since my Bullitt has a Maximum Motorsports Grip Box, we did have to remove the car’s torque arm in order to do this, but of course, if your Mustang isn’t so equipped, you can install the engine and transmission in the same manner as we did. The oxygen sensors you see hanging will be connected to BBK Performance extension harnesses to mate them with the factory harness.

29. With the engine in the car and running, it was time to add the Bullitt’s new BBK Performance fuel pump ($289.99). D1 wanted to make sure the engine was in good shape before going back down below to install the fuel pump. BBK Performance’s fuel pump is a direct-replacement for the factory pump, and is available for your ’98-’04 Mustang V-6, and GT, and ’98-’01 Cobra. It’s a 300-lph fuel pump designed to drop right into place of the factory fuel pump module.

30. Installing the BBK Performance 300-lph fuel pump was without question the easiest fuel-pump install ever. The hardest part was dropping and reinstalling the tank itself. Otherwise, you release the tabs on the stock fuel pump module, pull it out, and drop the BBK pump module in place. It really is that easy, and our Bullitt will have plenty of fuel for the new 5.0-liter stroker engine. 5.0

On the Dyno

For our Bullitt’s dyno session, we first had to break-in the Centerforce DYAD clutch for 500 miles before going full throttle, then we made the trip over the Brothers Performance in Deland to have James Gordon from Tuning by James work his magic. James is thorough, so we knew we were in good hands. Plus, he performs all the tuning for Brothers Performance’s car shows, and BBK Performance parts packages.
Before our Bullitt’s new 5.0-liter engine, it made roughly 245 horsepower and 286 lb-ft of torque at the wheels. I know, nothing to write home about. After the Ford Racing/Trick Flow 5.0-liter installation, those numbers jumped significantly to 338 horsepower and 331 lb-ft of torque. We had hoped it would make more power, considering the numbers we saw from Ford Racing’s engine dyno test. We used the same products as Ford Racing, so we were kind of dumbfounded by what the Bullitt made. In talking to Trick Flow reps, they see almost the same power from a stock 4.6 with the Trick Flow top-end kit. However, in our testing, the combination climbs like a mountain until 5,250 rpm, then it kind of flattens out. We can only reason the engine needs more air than these cams are able to provide. Perhaps with a bit more duration from the cams would provide more power output, but for a Two-Valve to make almost 340 horsepower at the wheels, and remain daily driver friendly is pretty good. For now, the Bullitt runs great, s
So we got some flack for too much silver when we posted the engine picture on Facebook, but as you can see, as installed in the car, you know this thing looks good, and the engine’s various hoses and harnesses break up the silver perfectly. James is familiar with SCT software so we chose to run a SCT BA2600 mass air meter for the install. If you’ve been wanting to build a Two-Valve for your Mustang, here’s your answer. Get out there and build your own.

RPM Power Torque Power Torque Power Torque
2,300 109.62 250.31 118.72 271.10 9.10 20.79
2,400 113.90 249.25 125.90 275.50 12.00 26.25
2,500 118.23 248.39 131.70 276.69 13.47 28.30
2,600 122.69 247.83 138.07 278.89 15.38 31.06
2,700 127.31 247.66 144.63 281.34 17.32 33.68
2,800 131.22 246.13 151.88 284.89 20.66 38.76
2,900 136.87 247.88 156.53 283.50 19.66 35.62
3,000 143.02 250.39 160.21 280.49 17.19 30.10
3,100 150.52 255.01 167.25 283.36 16.73 28.35
3,200 159.72 262.14 174.17 285.86 14.45 23.72
3,300 168.51 268.19 182.59 290.59 14.08 22.40
3,400 176.57 272.75 194.09 299.81 17.52 27.06
3,500 182.21 273.42 203.26 305.02 21.05 31.60
3,600 188.09 274.41 213.32 311.22 25.23 36.81
3,700 195.26 277.17 219.27 311.25 24.01 34.08
3,800 203.05 280.64 226.47 313.01 23.42 32.37
3,900 210.95 284.08 233.41 314.33 22.46 30.25
4,000 216.10 283.74 243.70 319.98 27.60 36.24
4,100 223.79 286.68 252.71 323.73 28.92 37.05
4,200 227.33 284.28 260.52 325.78 33.19 41.50
4,300 230.10 281.05 271.40 331.50 41.30 50.45
4,400 233.00 278.13 277.72 331.51 44.72 53.38
4,500 234.83 274.08 283.45 330.84 48.62 56.76
4,600 238.41 272.21 289.26 330.27 50.85 58.06
4,700 240.51 268.76 295.99 330.76 55.48 62.00
4,800 241.73 264.50 302.23 330.70 60.50 66.20
4,900 243.41 260.90 309.53 331.77 66.12 70.87
5,000 245.20 257.56 314.04 329.86 68.84 72.30
5,100 245.34 252.66 321.05 330.63 75.71 77.97
5,200 243.45 245.88 324.66 327.92 81.21 82.04
5,300 242.57 240.38 327.52 324.57 84.95 84.19
5,400 239.75 233.19 327.33 318.36 87.58 85.17
5,500 237.99 227.27 330.15 315.28 92.16 88.01
5,600 234.00 219.46 329.71 309.23 95.71 89.77
5,700 233.89 215.51 331.35 305.31 97.46 89.80
5,800 231.93 210.02 333.24 301.76 101.31 91.74
5,900 229.38 204.19 335.66 298.80 106.28 94.61
6,000 227.48 199.13 334.28 292.61 106.80 93.48
6,100 n/a n/a 338.75 291.66 n/a n/a
6,200 n/a n/a 337.14 285.61 n/a n/a
6,300 n/a n/a 336.02 280.13 n/a n/a
6,400 n/a n/a 333.52 273.71 n/a n/a


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