0 Vortech-Blown 351W Dyno Test

Modern Ford performance is alive and well, just ask any late-model Mustang owner. While the current crop of Coyote 5.0-liters are impressive performers, you are not as likely to find one at your local wrecking yard. Even if you were to come across a Coyote for sale, it would be considerably more expensive than the many 351 Windsors we found on our latest trip to the junkyard.

There were no Coyotes to be had, and only a few mod motors (all of which were the Two-Valve 4.6- and 5.4-liter variety), but the yard was full of the fuel-injected 5.0- and 5.8-liter Windsor motors. Sure, the early small-blocks can’t compete with a Coyote (or mod motor) in stock trim, but the one thing they have going for them is tremendous aftermarket support.

Taking the 351 Windsor to the max meant combining the right bolts-ons with intercooled boost!

Taking the 351 Windsor to the max meant combining the right bolts-ons with intercooled boost!

…The answer to any performance question is almost always “boost.”

Couple the availability of upgrades with endless years of research and development performed by enthusiasts, and you have the makings of a mild motor just begging to get wild. To illustrate the hidden potential of an injected 351 Windsor, we upgraded a 5.8-liter V8 with better hardware then added boost. The result was one impressive street motor, with plenty left on the table should you decide to get serious.

For those that might be new to the performance world, the answer to any performance question is almost always “boost.” Whether it’s street or strip, stock or modified, everything is better with boost. The only thing cooler than boost is (of course) intercooled boost. To drive this point home, we applied intercooled boost to a 351 Windsor.

Before running on the dyno, we augmented the 351W truck motor with a Comp cams upgrade. The XE282HR cam featured a .565/.574 lift split, a 232/240-degree duration split and 112-degree lobe separation.

Before running on the dyno, we augmented the 351W truck motor with a COMP Cams upgrade. The XE282HR cam featured a .565/.574 lift split, a 232/240-degree duration split and 112-degree lobe separation.

Boosting Performance

In this case, a Vortech V3 Si supercharger supplied that boost. On paper, the V3 certainly looked impressive, capable of flowing 1,150 cfm, delivering up to 22 psi and producing upwards of 750 horsepower (a rating we know to be on the conservative side). None of those upper limits would ever come into play on our Windsor, but it was nice to know the V3 Si offered such high adiabatic efficiency (meaning lower charge temps under boost). Naturally, we also liked the self-contained oiling that eliminated the need to supply a high-pressure feed or provide a drain-back in the oil pan.

The Edelbrock, aluminum E-CNC heads feature high-flow, 185cc intake ports; 75cc exhaust ports; and 59cc combustion chambers. Note the use of beehive springs and Comp Cams cast-aluminum roller rockers.

The Edelbrock aluminum E-CNC heads feature high-flow, 185cc intake ports; 75cc exhaust ports; and 59cc combustion chambers. Note the use of beehive springs and COMP Cams cast-aluminum roller rockers.

Boost from any source can best be described as a multiplier of the normally aspirated power. The more powerful the normally aspirated combination, the more power it will make under boost. Knowing this, we made sure the 351 Windsor was plenty powerful before adding the Vortech. Starting with a high-mileage, junkyard 5.8-liter, we retained the stock short-block, but augmented the induction with components from Edelbrock and COMP Cams.

Vortech V-3 Si Performance Specs

Internal Step-Up Ratio: 3.61:1

Max Speed: 52,000 rpm

Max Boost: 26 psi

Max Flow: 1,150 cfm

Max Power: 775 horsepower

Peak Efficiency: 78 percent

We swapped out the stock truck cam in favor of COMP’s Xtreme Energy 282. The XE282HR features a .565/.574 lift split, a 232/240-degree duration split and 112-degree lobe separation. The cam was teamed with a set of Edelbrock’s E-CNC 185 heads retained by ARP fasteners. As their name implies, these heads featured 185cc intake ports that flow a whopping 292 cfm, enough to support 600 horsepower on the right application. Feeding the heads is an Edelbrock Performer RPM II upper and lower intake fitted with a set of FAST 36-lb/hr injectors, an Accufab 75mm throttle body and a Holley HP fuel-injection system.

A two-piece Performer RPM II upper and lower intake topped the E-CNC heads. This long-runner intake offered a nice balance of torque and top-end horsepower. Feeding the Edelbrock intake was a 75mm Accufab throttle body. We bolted up the IAC but didn’t utilize it with the Holley HP management system.

Natural Progression

Before installation of the supercharger, we ran the modified 351W on the dyno using a set of 1 ¾-inch Hooker headers, an MSD distributor and a Meziere electric water pump. With this configuration, the naturally aspirated 351W delivered peak outputs of 418 horsepower at 5,800 rpm and 423 lb-ft of torque at 4,700 rpm.

This MSD billet distributor and matching plug wires handled the ignition chores. Spark energy is doubly important on a supercharged application.

This MSD billet distributor and matching plug wires handled the ignition chores. Spark energy is doubly important on a supercharged application.

At this boost level, the supercharged and intercooled 351W produced peak numbers of 626 horsepower and 577 lb-ft of torque.

With a proper baseline recorded, it was time for some boost. We made short work of installing the Vortech V3 onto the awaiting Windsor, including the air-to-water Maxflow Powercooler. Though we ran other pulley combinations, the best results came from a 3.0-inch blower pulley run in conjunction with the supplied 6.0-inch crank pulley. This produced a 2:1 drive ratio for the blower. When we combined this with the internal step-up ratio of 3.6:1 and 6,000 rpm engine speed, the pulley combo produced a maximum impeller speed of 43,200 rpm. This was well below the 52,000 rpm limit recommend by Vortech, and resulted in a maximum boost pressure of 8.5 psi.

At this boost level, the supercharged and intercooled 351W produced peak numbers of 626 horsepower and 577 lb-ft of torque. Datalogging during the run indicated that the intercooler was knocking over 70 degrees of charge temperature out of the charge air (from 88 to 159 degrees). We did notice a slight drop in boost across the core as well, an indication that it might be time to look for a larger core if you plan to max-out your Windsor, but for now, this supercharged 351 was one cool customer.

Run on the engine dyno at Westech Performance, the naturally aspirated 351 Windsor produced peak numbers of 418 horsepower at 5,800 rpm and 423 lb-ft of torque at 4,700 rpm. The upper intake was reversed for testing to clear the fuel pressure regulator.

Run on the engine dyno at Westech Performance, the naturally aspirated 351 Windsor produced peak numbers of 418 horsepower at 5,800 rpm and 423 lb-ft of torque at 4,700 rpm. The upper intake was reversed for testing to clear the fuel pressure regulator.

In anticipation of boost, we replaced the 36-lb/hr FAST injectors run on the naturally aspirated combo with 50 pounders from Holley. To monitor inlet air temps, we positioned an air-temp sensor just behind the throttle body on our supercharged 351.

We then installed the blower bracket and mounting plate. The mounting bracket was secured to the Edelbrock cylinder head using the supplied hardware. No other accessories were employed on the test engine. The supplied 6-inch blower pulley was secured to the factory damper. This resulted in a blower drive ratio of 2:1 when combined with the 3.0-inch blower pulley. A mounting plate with five 3/8-inch mounting bolts and washers retained the Vortech V3 centrifugal supercharger. Though we also tested a Ti-trim supercharger, the self-contained V3 was more than adequate but at this power level.

The highlight of the intercooled kit was, of course, the Maxflow Power Cooler. Positioned between the supercharger and throttle body, the charge air cooler helped drop inlet air temps by over 70 degrees. The Powercooler was given a steady supply of ambient dyno water for our testing. There was plenty of power left in the combination, but you might think about upgrading the intercooler if you plan on elevated power levels.

It is evident from the power numbers that the Vortech supercharger improved the power output of an already healthy 351W. Starting out life as a junkyard dog, the Windsor was upgraded with Edelbrock E-CNC heads, a COMP Cam and RPM II upper and lower intake. In normally aspirated trim, the 351W produced 418 horsepower and 423 lb-ft of torque. After installation of the intercooled Vortech V3, the power output jumped to 626 hp and 577 lb-ft of torque. The Powercooled Vortech added a cool 208 horsepower and 154 lb-ft of torque to the bottom line. To illustrate the drop in inlet air temps, we positioned thermal probes before and after the MaxFlow PowerCooler. Running a peak boost of less than 9 psi, the inlet air temps coming out of the blower registered nearly 160 degrees, but the charge cooler dropped these below 90 degrees. Cooler air not only helps improve power production, but it allows for increased boost and timing.

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