40-Valve Flyer

Even Ford Motor Company builds project cars, and we thrash its latest -- a V-10-powered Mustang that smells a lot like the next R-model.

The 21st Century horsepower war is starting to make the '60s musclecar era look like a tea party. Technology has allowed the Big Three to maximize performance of EFI systems and when coupled with the latest engine and vehicle designs, amazing things happen.

Take, for example, the 4.6-liter '03 Cobra. Its DOHC engine is rated at 390 hp, but it really makes about 425 and can run mid-12s with ease, all with every creature comfort. The Lightning is not far behind with 380 ponies and enough torque to make you grin like a fool. Chevy's top dog is the 405-horse ZO6 Vette, a 12.0 player and Chrysler joins the mix with the 500hp Viper and a modern Hemi V-8 that comes to the table with 345 hp. The next incarnation of the fabled Pontiac GTO is just months away from production.

Now, Ford will match the Viper with the 500hp GT super car, and the next Lightning should fall in right behind that. Performance is alive and kicking and it's only getting better.

In order to stay on top, a company must be thinking ahead and the Blue Oval boys are doing just that.

Enter the Boss 351 seen here. Not a retro remake of the popular '71 model, this modern Boss is capable of ripping the asphalt from under the tires. Unlike the filly that previously wore this moniker, which had a 330-horse, 351 Cleveland and a four-speed, this Boss Mustang has a current production body and is motivated by a prototype V-10 making 500-flywheel hp.

The Boss is just the latest skunkworks project built by Ford Motor Company. It's an engineering exercise. Yeah, right, you're saying, Ford wouldn't build such a car. But before you write it off I urge you to read on. I'm sure you have lots of questions and so did we. Are they going to build it? Could it be the next R? What happens if they supercharge it? And most importantly, how did it come about?

For starters, the V-10 Boss is not a 6.8-liter Triton truck engine dumped in a Mustang shell. Instead, it is a short-stroke V-10 that's similar to the 4.6. The block is cast from aluminum and topped with four-valve heads and a free-flowing intake, pirated partially from the Cobra R. It has power to spare and can be revved past 7,000 rpm. Do I have your attention yet?

The hopped up V-10 is a product of Ford's Engine Manufacturing Development Operations (EMDO), the same group that designed the Modular V-8s and the Triton V-10. According to Nick Twork of Ford Public Affairs, "The guys in the engine development area are real car guys. They have a passion for this stuff and this V-10 allows them to show it. But they wouldn't waste time on something that didn't have production feasibility."

That's not to say that Ford is ready to churn out a 500hp V-10 engine in our favorite ponycar, but Twork admitted that the possibility certainly exists that an engine like this could make production.

Believe it or not, the project began as nothing more than a "what if" idea and progressed into a running prototype. As I just mentioned, it uses current 4.6 architecture (3.55-inch bore x 3.54-inch stroke), but with two additional cylinders. Because of the shorter stroke, this V-10 sports a 351-cubic-inch displacement and offers high-rpm capabilities. A special block was cut and pasted together and then the aluminum block was cast and machined. The 10-cylinder block was then fitted with a billet 4130 common-pin crankshaft (five journals, two rods per journal), rather than the single-pin crank (one rod per journal) found in the 6.8 V-10.

According to Kevin Byrd of Ford's Powertrain Research & Advanced Engines, the Boss is an "odd-fire" engine, because the cylinders do not fire at evenly spaced intervals. They fire at 90 and 54 degrees. Connecting rods are straight out of the '03 Cobra, while the pistons are '00 R-issue and they compress the air/fuel mix into '00 Cobra R-style DOHC heads.

Like the block, the heads were formed using casts that were "cut and pasted." The cams and valves are of the same dimensions as the 5.4 R model, albeit with a few extra lobes, and they are driven by a stock 4.6 DOHC chain setup.

Topping the V-10 is a hand-built aluminum intake that was pieced together from two Cobra R units. It is a cross-ram design with twin plenums (with a crossover) and straight runners. A 70mm throttle body feeds each plenum, and air is metered by two 80mm mass air meters. In order to fire the coil-on-plug ignition they went with twin 6.8-liter EEC V processors (one per side) and the fuel system consists of a Weldon pump with 30-pound injectors fitted to customized Vortech rails. A Paxton regulator keeps pressure to 39 psi. EMDO backed the V-10 with a Cobra clutch, a Pro 5.0-shifted '01 Cobra R six-speed, and a Ford 9-inch with 3.73:1 gearing. In addition, the Mustang sports coilover front struts and Maximum Motorsports lower controls arms with stock-type shocks and uppers in the rear.

The Boss is definitely different than most of the project cars we've seen from Ford. Pessimists will still see this glass as half empty, but optimists will see the benefit of such a car. Most Ford fans were thrilled with the potential of the '00 Cobra R, but annoyed at the price tag and the availability. Then two years later Ford stepped up and built the Terminator Cobra. It is $15,000 cheaper than the R, just as quick, and can be much more easily modified. And without prototypes like the Super Stallion and the like, Ford would not be able to build and sell such a car as the supercharged Cobra. In our mind there is no doubt the technology at work here will some how, some way make production, whether in R or other trim.

The Test
It took about one week from my original phone conversation with Ford Public Affairs to book the track and a flight. And before I knew it I landed in the Motor City and headed over to Milan Dragway, where the Mustang was waiting. From a distance the silver Stang looked pretty cool, but it's no trailer queen. Upon closer inspection I realized this mule had a well-worn interior, with telemetry scattered throughout. There were two exhaust temperature gauges covering the passenger-side airbag, a pair of computers on the floor, gauges on the A-pillar and a big Ford breakout box loaded behind the passenger seat. All this was necessary to run the mammoth V-10 sitting, long, lean and mean under the Cobra R hood.

It was also evident the boys in the EMDO built this baby right, with a six-speed and 9-inch rear, so we'd be able to drop the hammer and shift as hard as we could without fear or breakage. Furthermore, the Mustang was driven to the track, not trailered-- they didn't care how hard I drove it. That's confidence, especially given my track record with Ford test vehicles.

Since they drove it in from Dearborn, warming the car wasn't necessary. I made my formal introductions and did a quick photo shoot. Then, I hopped in, adjusted the seat and fired the engine. The exhaust note was like no other Mustang. It was Viper-like, spitting out a low burble at idle and a throaty note once the throttle was cracked. I let the engine idle for a second while I strapped on my helmet and Kevin Byrd reassured me I could drive it hard. He had no fear of me breaking this thing--I was shocked.

I gave Byrd the nod, tossed up the driver's side window and then rolled up and heated the BFGoodrich G-Force tires until they smoked. Next, I eased up, staged, reved the engine to 2,500 and milked the Stang off the line. There was plenty of bite initially, but the tires broke loose at the top of first gear and spun wildly after I shifted second. I pedaled the gas and found some traction, then I ripped third and forth at redline (read: 6,900 rpm). The timeslip for the first run read 13.06 and the trap speed was 114.19 mph. The engine was wonderful, making awesome power from about 3,000 to 7,000 rpm, but hooking was another story.

I followed the first run with a smoother application of power and a 12.97 at 115.45. Then I tried the left lane and clocked a 12.83 at 116.25. The Mustang was no match for the combination of cold track and street tires, so we decided to trade the street radials for Mickey Thompson ET Streets that Mustang racer and friend Barry Shepard brought along.

I was anxious to dump the clutch and get to some serious powershifting, but I had no idea how good the traction would be so I did a moderate burnout, staged, and revved the engine to 3,800 rpm. When I dumped the clutch the Mustang leapt forward, then bogged badly. The big V-10 pulled way back, almost to idle, then took off like a rocket and I plowed the shifter through the gears with the throttle blades held to the stops. The e.t. plummeted to 12.14 and the speed was up to 116.61 mph, our best of the day. And even with the bog, the 60-foot time dropped from a 2.28 best to a 1.95.

With a 9-inch and six-speed in place there was little fear of hurting anything so I turned the launch rpm up to 5,500 and let it go. Our 60-foot time fell again, this time to a 1.76, and the resultant elapsed time dropped to an 11.76. Speed was now up to 117.81 mph, but we weren't done yet.

Despite the displacement (351 cubic inches), the V-10 was not really happy below 3,000 rpm. Not that it ran poorly, but it really loved being revved high. Power came on strong at about 3,500 and it pulled like an animal right up to the rev limiter, which was set at 7,000 rpm. I liken the power to that of the '00 Cobra R, but with more oomph down low and more power above 6,500. I attribute this to the shorter stroke (3.55 vs. 4.16 inches). The combination of the four-valve heads and the extra cylinders made this one fun engine to drive.

Okay, if the 5,500-rpm launch was good then a 6,000-rpm launch would be better, right? Yes, indeed. The higher I revved it the faster we went and this time I clicked off an 11.56 at 116.84 mph. The Boss 351 engine was running like a Timex, taking all I could give it, but the clutch was getting hot (I knew this because I could smell it) and I didn't want to burn it up just yet. Byrd and I were happy with the 11.56, but I wanted to give it one more try. Byrd wanted the best e.t. and said, "Do what ever you have to."

To me this meant jacking the rpm to the limit. I gave the clutch a 30-minute cool down and climbed back aboard. A second-gear burnout got the Mickeys hot and I staged as shallow as I could. This time I simply matted the gas and watched the tach needle shoot to the 7,000-rpm limit. The engine bounced off the limiter and shortly thereafter I snapped my leg from the clutch and the Mustang took off. The tail kicked to the left as the tires spun (slightly), but the car was accelerating and the spin kept the rpm in the peak power range. About 30-feet out the tires locked up and at 6,900 I tapped the clutch and pulled back as hard as I could.

The gearing in the Tremec six-speed kept the rpm in a tight powerband and each time the engine climbed to redline I grabbed a gear. Before I knew it I was in fourth and trucking to the stripe. The V-10 felt stronger than it had all day and the e.t. showed it. This time we scored an 11.51 at 118.19 mph. The team of Ford engineers were thrilled and couldn't wait to report back (plus, the car was still in one piece), but I wasn't done.

I still wanted to give the V-10 one more try with the BFG street tires. Shepard and Richard "Tiny" Mitchell jacked up the car and slapped the Saleen wheels back into place and I gave it the old college try. Now, with more traction, I was able to get aggressive with the radial street rubber. Previously, with the street tires, my best 60-foot was a 2.28, but this time I got away with a 2.09 and the tire spin was minimal on the first-to-second gear change. This kept the car accelerating and the clock showed a 12.44 at 117.01, a big improvement over the 12.83 we ran earlier. I hot lapped the Mustang, this time powershifting, and the e.t. dropped to a 12.28 at 117.50. We made that our last run.

For comparison sake, we also ran the '03 Cobra Ford SVT was kind enough to lend us while we were in town. On this day, the best we could muster was a 12.83 at 110 mph. The Boss was a full 7 mph faster than the current king of all Mustangs in back-to-back testing. Yow!

After spending the afternoon with the Boss 351, I'll say Ford has hit on a winning combination. The V-10 is just about the perfect engine. It has a good sound and excellent drivability. I believe it is something that would appeal to the masses and could even be used in a variety of vehicles, both cars and trucks. It could be a special edition, or even an R-model. In my opinion it is too good to leave on the shelf. Will Ford ever build it? Who knows, but one thing is for sure--Ford is certainly showing the competition who's boss.