For most of us, the process of building an engine for our Mustang is a Herculean exercise in compromise. Elements of that compromise include physical size, driveability, reliability, upkeep and cash flow. Of all these elements, however, cash flow likely places the biggest demand on our automotive sensibilities. In even the most well intentioned of projects, the lack of cash flow can turn mountainous dreams into modest molehill realities.

But what if cost were a much smaller concern? What if you won the lottery? Or inherited a fortune? We're so shackled by the mental bonds of cost that sometimes we're even scared to dream, and dreaming is free.

Tommy Gourzis of Coopersburg, Pa., dared to dream, and then he dared to spend. Though the cost involved was huge – let's just say it was a very large stack of C-notes – Tommy built the engine of his dreams, a 422-cubic-inch Yates-headed, fuel-injected, nitrous-inflated street terror.

How Tommy arrived at this outrageous juncture is worth noting. Like many of us, his story is littered with broken parts, lackluster performance and mondo dollars spent. Gourzis says, "Back in high school I went through three 302s. I had a Kaufmann motor in an '87. That motor blew. Then I went to another 302 but it wasn't fast enough so I sold it. Then I went to a regular 351 Windsor. It had Dart heads, a Victor Jr. intake and a 750 Double Pumper.

"I got tired of it and went to my first stroker motor. That went good until last summer, when I bent the crank. So I decided that for my next motor I wasn't going to take it easy. If I had built this one from the start I would have saved a couple of bucks."

Incredibly, Tommy's decision to build an all-out shootout motor for the street was, at least in part, born out of cost savings!

For street use, reliability was the key concern. Tommy's experience with his stroker engine was enough to convince him that cubic inches were the best solution for the street, the more the merrier. Gourzis obtained an SVO 9.2-inch-deck 351 Windsor block and a forged Crower 4-inch stroke crank with the intention of building a 400-plus-cubic-inch mill. To turn these parts into a working engine, Gourzis brought them over to Second Street Speed in neighboring Perkasie, Pa.

"Tommy wanted to run as fast as he could afford without using any boost," says Lon Moyer of Second Street. "His approach at that point was good cylinder heads and nitrous."

Stroker motors solve many practical problems faced by other power-adder engines with regard to octane, detonation, reliability and strength. They are capable of turning a large amount of air and fuel into power without suffering the same woes of turbos, blowers and nitrous. But all is not perfect in stroker–land.

Large-cube motors – Ford small-block strokers in particular – suffer from congenital defects unique to them. The ratio of valve area to swept volume, for instance, leaves many stroker engines over 400 cubic inches wheezing for breath after 5000 rpm. The problem is that the valves and ports simply cannot move as much air per cubic inch of displacement compared with their smaller siblings.

This calls for a serious take-no-prisoners cylinder head. And when it comes to mega Ford cylinder heads, there's only one choice: Yates.

"The Yates head has a superior intake runner and combustion chamber design," says Moyer. "It's got the proper location of spark plug, and the short turn radius is real good. The intake runner carries fuel well so fuel separation is minimal."

Second Street turned to Weld Tech of Brownsburg, Ind., for its CNC-ported version of the Yates/SVO piece. This was deemed the best way the achieve the flow numbers necessary to support 700 naturally aspirated horsepower in a streetable 400-plus-cubic-inch package. At 28 inches of Hg, the Weld Tech flowed 341 cfm at .600 inch lift on the intake and 229 cfm on the exhaust (see flow chart).

The other problem encountered with stroker motors is poor rod ratio. Once rod ratio dips below 1.6:1, factors like piston speed and wear become a concern. With a rod length of 6 inches and a stroke of 4 inches, rod ratio is reduced to 1.5:1 in Gourzis' 422. This is not optimal, but with the large dosage of torque characteristic of strokers, and a camshaft optimized to widen the power-band, the folks at Second Street felt that very little would be given up by limiting engine speed to a safe 7500 rpm.

To further maximize flow into and out of the engine, Second Street Speed opted for a solid-roller camshaft in combination with lightweight titanium valves, retainers and keepers. A low valvetrain inertia coupled with a fast-rise lobe profile increases the quantity of flow for any given cam duration; this is especially important for a valve-limited engine like Gourzis' 422-cubic-inch stroker. Second Street likewise equipped the 422 with 2.10-inch/1.60-inch Del West titanium valves activated by Jesel 1.7:1 shaft-type rockers and a Comp Cams solid-roller cam with .714 inch lift and 268/272 deg. of duration at .050 inch.

With such radical valvetrain acceleration, a heavy Winston Cup type valve spring from Competition Cams was employed. These Pacaloy springs provide 240 lbs. of pressure at the seat and a whopping 600 lbs. at .600 inch lift. This elevated pressure is required to safely keep the solid Competition Cams roller lifters in contact with the cam lobe's trailing flank at higher engine speeds.

High spring loads put additional stress on cam bearings, particularly in situations where endurance is an issue. In place of standard performance cam bearings, Second Street installed roller cam bearings from Roush. These bearings are used extensively in Winston Cup applications and were perfect for Gourzis' street engine. Higher strength, lower friction and better heat management will help the bearings stand up to the high valve spring pressure when used on the street for longer periods.

In the stratosphere of Ford performance, induction component choices are no longer made by calculated guess. Even the most experienced engine builders can no longer entrust to experience alone a choice of camshaft, intake or exhaust component.

As an aid, engine designers employ computer programs to refine the specifics of a basic combo before precious time and money are spent on hardware. Moyer says, "We use a computer program to run some numbers before we order any parts for a motor. It's called Dynomation. You can basically simulate a whole engine combination with flow numbers, bore, stroke, compression ratio, intake runner design, headers, air/fuel ratio and lots more. The biggest thing we toyed around with was camshaft."

Through the Dynomation program (VP Engineering, 515/276-0701), many of the variables were nailed down, such as the 422's camshaft, 12.8:1 compression and 2-inch long-tube headers. One of the engine's most critical features, its intake design, however, was not determined by the Dynomation program. Although Moyer did experiment with runner length in the program, he opted to let Hogan's Racing Manifolds design the sheetmetal intake because of Hogan's extensive experience in building high-powered fuel-injected intakes.

The reciprocating assembly consists of custom J&E forged pistons, Oliver 6-inch billet rods and a Crower forged crankshaft. When combined with the Yates head's 63.5cc combustion chamber, the custom domed piston yields a compression ratio of 12.8:1. A full-floating .927-inch Chevy wrist pin rides in a high-pivot location without infringing on the piston's oil ring groove. Second Street declined to divulge the specifics of the ring package other than to say it contains a moly top ring and a cast-iron second ring.

Although great efforts were taken to obtain maximum horsepower in naturally aspirated form, Tommy wanted to have more power in reserve when it came time to race the dual-purpose vehicle on the shootout circuit. Since the recipient Mustang has been back-halved, narrowed and caged, it is capable of applying quite a bit more than the 422's natural power output in a race environment with slicks.

Tommy felt it would take at least 1,000 hp to be competitive in most Mustang shootout situations. Provision for a nitrous oxide fogger system was made from the outset in order to reach the target power level, but that would require the motor to make around 700 hp in naturally aspirated trim.

All of this power is predicated on the strength of the bottom end, so all steps were taken to keep the expanding gases where they belong, inside the cylinder wall. The block was bored to 4.100 inches, torque-plate honed, deck equalized, and stress relieved with the Metalax process. The reciprocating assembly was also computer balanced (internally) to reduce vibration, excessive wear, and the possibility of disintegration at high speed.

Second Street Speed also chose a Danny Bee beltdrive for the 422. Among the reasons cited by Moyer for using the Danny Bee were that the unit allows for quick adjustment of the cam timing and that the beltdrive dampens harmonics in the valvetrain better than a chain or geardrive.

From a cost standpoint, a carbureted fogger combination would have been the easiest way to make the requisite power, but a fuel-injected engine was more in keeping with Tommy's non-compromise strategy. Street manners for an engine of this power virtually dictate the use of fuel injection. From a tuning perspective, a programmable fuel injection setup would be more flexible than a carb, and nitrous management would be considerably simplified.

With these criteria in mind, Second Street chose the aforementioned Hogan's fuel-injection manifold, a Cutler throttle body, and a Motec M48 Pro controller with a Motec IEX ignition expander module. The Motec unit has a 32-bit processor that operates at a 33-Megahertz clock speed, making it the fastest after-market engine management system currently available.

Among the Motec's advantages is its ability to control fuel through Lambda feedback, meaning that the unit can seek a specific table-based air/fuel ratio via a wide-band oxygen sensor in real time. This simplifies the setup and tuning process when combined with the Motec's ability to perform multi-channel data-logging at up to 20 times per second.

We'll go into more detail about the Motec fuel injection and ignition system in next month's installment, when we give you complete dyno results with and without nitrous.