Michael Galimi
February 8, 2010

"I want big power," was the comment from Editor Smitty to Mike Dezotell and myself during a brainstorming meeting last month. The power he was referring to is the little supercharged Two-Valve bullet that resides under the hood of a 2000 Mustang GT at Dez Racing (Seekonk, Massachusetts). It has been the subject of multiple articles over the past few issues, which began with the addition of a pair of newly released Trick Flow Twisted Wedge Street/Strip 4.6L cylinder heads.

Dez and I were left thirsting for more after sampling a healthy gain with the addition of the new heads in stock form. In follow-up stories, we added a larger ProCharger D1SC blower, a Lethal/Fore Precision fuel system with enough fuel pump capacity to support an EFI-Renegade car, Ford Racing 80-lb/hr injectors, F-82 cams from Anderson Ford Motorsport (AFM), and Kooks long-tube headers. The mild 284ci engine spun the dyno to 579 rwhp, but we were way short of the true potential of this combination given its healthy induction and large ProCharger blower. That is when Smitty issued the decree for max power.

This month, we pulled out all of the stops and went in search of 600-plus rwhp. We increased the airflow with a set of ported Trick Flow heads and a new intake manifold, which should effectively help the engine rev higher. The Trick Flow 4.6L Street/Strip heads were shipped to Fox Lake Power Products for a workout on its CNC machine. Fox Lake cleaned up the intake and exhaust ports, but left the Trick Flow valves in place (1.84/1.45). As far as we know, this is the first company to offer CNC-ported versions of the Trick Flow 4.6L heads. We ran the heads over to Steve LaPoint Racing Engines to get independent flow-bench numbers. It is the same shop that we used to flow the ported OEM heads and out-of-the-box Trick Flow pieces. The Fox Lake porting added 9 cfm when compared to the out-of-the-box heads-on both the intake and exhaust ports. Now the heads flow 259 cfm on the intake and 189 cfm through the exhaust port, both at 0.500-inch lift. Moving to 0.600-inch lift, the flow numbers increase to 269 and 195 for a gain of 16 and 6 cfm, intake and exhaust respectively.

Getting more rpm from this bullet was a priority and not one that was unrealistic. Better flowing heads would equal more power. The engine consumes more air at higher rpm levels and/or piston speeds. The Trick Flow Twisted Wedge 4.6L Street/Strip heads have higher flow rates through all lift ranges and our heads allow the engine to consume a higher volume of air per cycle.

"The cross-section of the Twisted Wedge port and its velocity was optimized despite the constraints of Ford's layout. We had to deal with the head-bolt boss on one side of the port, the spark plug on the other side, and the spring pocket on the roof. Had we not had those three constraints, we could have made a better port. But given the situation, we made a port that works as designed by giving very good torque and upper rpm power," commented Al Noe of Trick Flow. Fox Lake didn't alter the port design (shape), the CNC process merely trimmed away a little material to help more air pass through the ports.

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Our original plan was to use a hand-ported Fox Lake P-51 intake but it didn't make it back in time for the test. That forced Dez to pull a Trick Flow intake off the shelf to put in its place. We knew the Trick Flow wouldn't have a problem sitting on top of our better-breathing heads and not lose torque in the lower rpm ranges. "There is a balance between the cross-section area and length of a port (intake manifold port). Every design, unfortunately, is a compromise. The TFS manifold was designed to feed a 4.6L to 8,000 rpm, while minimizing a shift in the torque curve toward lower speeds. This is why you see dual-port intakes or charge-motion plates on smaller, newer engines. At slower engine speeds, less air is consumed, minimizing the cross-section increases velocity for improved cylinder filling and torque production, while at high engine speeds, cross-section is maximized to supply the volume being consumed by the engine," said Noe. In the end, despite the power the '00 Stang makes, it's still a street car and the intake is a nice blend for its dual-purpose use. The BBK 70mm throttle body was carried over from our original testing.

We continued to employ a ProCharger D1SC blower with the company's two-core front-mounted intercooler. It is a healthy street blower capable of producing enough air to make 925 hp (at the crank) on a properly prepared engine-according to ProCharger. After experiencing belt slip in Part 2 ("Two-Cam Belt-Slippin' Jam," Dec. '09), we added a ProCharger eight-rib pulley conversion kit. Initially, we were stuck with a 3.40-inch blower pulley, which regulated boost to 17 psi. Not to disappoint Smitty, Dez decided to get a 3.150-inch blower pulley for serious boost. It would spin the supercharger much harder when combined with our new 7,000-rpm redline. "I ordered a pulley from a new company, Carbonite. The Pro-Grip pulley is all the rage in the NMRA EFI-Renegade ranks where they are limited to an eight-rib pulley setup. It helps belt grip through a special coating applied to the contact area of the pulley," commented Dez. The Pro-Grip's texture is rough and reports from the streets say it doesn't tear up the belt like some other traction-enhancing pulleys on the market. The Snow Performance methanol injection kit was also used so Dez could get more timing to go along with the big boost. We didn't want to let the boss down, and this plan was sure to bring big power from the 2000 Mustang GT street car.

The short-block remained the same-a stock block bored 0.020 inch (3.572-inches), cast-steel crank (stock 3.543-inch stroke size), forged pistons, and cheap steel rods. Total displacement checks in at 284ci using the V-8 displacement formula of Bore x Bore x Stroke x 6.2832. While our tiny engine held up to a barrage of chassis dyno tests at 20 psi of boost and over 7,000 rpm, it won't last long at that level. We definitely recommend adding a billet crank and even a good set of billet rods if you dare to venture in the realm of this combination.

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On the dyno, the car did as we expected-within a few pulls the 284ci mill produced 630 rwhp and 520 rwtq. Dez cranked the timing to 21 degrees, thanks to the octane enhancement from the Snow kit. With the meth flowing and the boost pressurizing the engine to the tune of 20 psi, the Stang screamed to max power at 6,800 rpm. And to add icing to the cake, these numbers were in SAE correction factor-like the other tests with this vehicle. Dez converted the numbers to STD and the power increased to 648 rwhp. Some shops utilize the STD correction factor rather than SAE. The difference between the two is how the computer converts the data based on a pre-determined weather condition. SAE converts the actual weather and power results to read as if the car was run on the dyno during a day with an air temperature of 77 degrees and a barometer reading of 29.23 InHg (99 KPa). The STD correction works off the weather model of 60 degrees and a barometer of 29.92 (103.3 KPa). STD will always read higher than SAE because it is correcting to a day representing cooler, drier air. Both correction factors use a humidity reading of zero. It's important to note that the automobile manufacturers such as Ford, use the SAE correction factor when testing.

The boost soared to 20 psi, which might not seem like a lot considering our big jump in pulley size. But it is actually a pretty good number considering we opened up the induction side with a larger intake and higher flowing cylinder heads. The induction upgrades provide less restriction, which in turn lowers the boost if the pulleys aren't changed. The reason is because boost is simply a measurement of restriction in the intake manifold (where the pressure is measured in most applications). By providing a freer-flowing setup, the same blower speed would show a lower boost reading despite providing the same amount of airflow. We increased the blower speed and saw three more pounds of boost on top of what the engine probably lost due to the new intake and heads.

"This is still a cast-crank motor. I don't want to push anymore than 630, which is way more than this short-block can handle for regular operation. The motor is seven years old. It ran great and I am really happy where we are at with it," said Dez. Hopefully Smitty is satisfied with a mid-600-rwhp street car combination too. (Editor's note: Yes I am!)

FLOW CHART: INTAKE
LIFT TRICK FLOW (PORTED) TRICK FLOW (UNPORTED) PORTED STOCK
0.100 69 cfm 58 cfm 59 cfm
0.200 130 cfm 125 cfm 110 cfm
0.300 189 cfm 177 cfm 158 cfm
0.400 235 cfm 223 cfm 189 cfm
0.500 259 cfm 250 cfm 209 cfm
0.600 269 cfm 253 cfm 219 cfm
EXHAUST TRICK FLOW (PORTED) TRICK FLOW (UNPORTED) PORTED STOCK
0.100 62 cfm 50 cfm 52 cfm
0.200 118 cfm 103 cfm 100 cfm
0.300 158 cfm 145 cfm 133 cfm
0.400 185 cfm 175 cfm 169 cfm
0.500 189 cfm 180 cfm 190 cfm
0.600 195 cfm 189 cfm 200 cfm

Flow Bench Notes
Bore size: 3.552
28 inches of water
Trick Flow heads feature 1.84/1.45 valves
Stock heads feature 1.78/1.45 valves
All heads tested at Steve LaPointe Racing Engines

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