The compressor moves 2,300...
The compressor moves 2,300 cc of air per revolution. Amazingly, it sits upside-down so the air exits from the top. This allows the flow of air to transition smoothly into the runners.
The Saleen supercharger kit retails for $4,999.99 and includes everything needed to do the job. The kit does come with an informative instruction manual with plenty of illustrations, but it's not for the inexperienced mechanic. "The Saleen instructions are great," says JDM tech Shaun Lacko, who performed the work. "All the parts fit well, as described, and the instructions tell you how to do everything. There's almost nothing to figure out on your own. It even tells you what tools you'll need."
Performing the swap entails discon-necting and/or removing a few underhood items such as the battery, the wiring, the hoses, the intake manifold, the alternator, and some of the front engine dress. It is also necessary to remove the front fascia in order to install the heat exchanger. Lastly, the kit includes a Saleen PowerFlash performance computer, which is tuned for 91-octane and meets the standards for warranty and emissions.
While we realize the Saleen computer is specifically tuned for the kit and it works beautifully, Amato planned to up the boost with an aftermarket blower pulley, so he and D'Amore of JDM agreed to tune the factory computer using Superchips Custom Tuning software. "We're going to try 6-, 8-, and 10-psi pulleys, though the 10 may be a bit much for the compression," Amato says. "I'd need a new tune each time, so I wanted to tune locally instead of sending the computer back and forth to California. That's also why we installed the Cobra 39-pound injectors."
Once the labor was completed, we hit the dyno and then the track. You may recall that in our test last month, the S281 Supercharged kicked out 390 rwhp and ran 12.50, so we had both the before numbers for this GT as well as another baseline for comparison. And the kit didn't disappoint, as Amato's Three-Valve now produced 430 hp and 398 lb-ft of torque. That's a gain of roughly 120 hp and 76 lb-ft of torque with only 3.5-4 psi of boost. Imagine how much the power will increase when the boost is doubled. But extra boost will have to wait for another day, as we wanted to get to the track and lay down some numbers.
The compressor sits neatly...
The compressor sits neatly under this uniquely designed intake system. Saleen says much of the low-end power comes from the long-runners in the intake manifold. While the inlet looks thin, it flows like gangbusters. "The shape of the 'snorkel' opening for the air tube is designed for maximum flow," says Cody White of Saleen, "and to maintain a constant volume of air as the air flows toward the rear of the engine, the housing widens and flattens out over the engine."
Going into the drag test, we knew the performance would be in the 12s. What we didn't count on was temperatures in the 90s, high humidity, and a low barometer reading. The weather was much better when we tested the last Saleen, but that's how the ball bounces. At least we can't be accused of always having killer conditions. So, with soup for weather we marched on and took Amato's Stang to the line.
The first attempt produced a non-stellar and extremely traction-limited 13.003 at 111.88 mph. Mounds of low-rpm torque caused spin off the line and crazy spin after the First-to-Second gear exchange. In fact, the GT smoked the tires all the way through Second, even though yours truly tried to pedal it. Finally, I hit Third and hooked up, but by then the run was a bust. At the 1,100-foot mark it was time to shift into Fourth, and then I crossed the stripe.
The next run, made immediately following with the engine hot, brought similar results, and the clock posted a 13.002 at 110.58 mph. The 60-foot times on those runs were 2.15 and 2.07, respectively.
We allowed the engine to cool, but we didn't use any ice or artificial cooling. We dropped tire pressure from 30 psi to 26 psi and we went back for another hit. This time I was smooth off the line with another 2.07 short-time, but I granny-shifted into Second to limit the spin. I was rewarded with a 12.80 at 112.15 mph. Sadly, the weather was getting even hotter and that was preventing us from besting the Saleen's 12.50, despite the fact that we had 40 more rwhp and were toting about with nearly 240 less pounds of baggage.
We had one last trick up our sleeves and that was to install a set of drag radial tires. With the potential for better traction, I was more aggressive in my launch technique. I got after it off the line (3,800-rpm launch with slight clutch slip) and the 60-foot dropped to 1.93 seconds. I powershifted Second--it hooked--and I marched on to a 12.40 at 112.18 mph. While we thought the GT could have run in the 12.30s, the hot weather was pressing us into submission. Amato took a turn, but didn't go any quicker, so we decided to park it until more boost was added. Then we could go for the 11s, even if the weather remained hot.
But even at Saleen's preset boost level, Amato and I were impressed with the performance, especially in the lower rev range. "The throttle response is 10 times greater now," Amato says. "Just hit the throttle and it moves. What I like the most is that the power comes on instantly and it pulls through all the gears. It's nice, but I would say we could make another 40-50 hp at the wheels once we up the boost. We [Downs Ford Motorsport] plan to sell the kits stock and upgraded with a cold-air, chip, and pulley package."