Wayne Cook
November 1, 2007

We've known for a long time that Superior Automotive in Anaheim, California, is a gold mine for Ford high-performance expertise. The folks at Superior Automotive work on all kinds of American muscle, but there's always something interesting going on from a Ford-performance perspective whenever we pay them a visit. From garden-variety Mustangs to the more esoteric visitors-such as a '48 Mercury convertible with a 460 conversion-on any given day, a visit to Superior always makes us feel like kids in a hobby shop.

In issues past, we visited the in-house carb shop and came away with extra horsepower. With more than 40 years of experience, Don Spaccarotella is the apostle of horsepower at the carb shop. He's especially adroit at resurrecting basket-case Holley four-barrel carbs. This time, we thought we'd throw him a curveball and see if he could get anything out of a brand-new Holley carb.

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The new Holley four-barrel is a 650-cfm unit sitting atop a fresh 351 Windsor. The double-pumper carb has a mechanical secondary, and the only alteration is that the choke has been wired open. The carb has about 2,000 miles on it, and the engine runs like gangbusters. Holley knows what it's doing when it comes to building carburetors, and a new Holley four-barrel will usually run fine right out of the box provided it's appropriately sized to the engine. Such is the case with our carburetor.

When we approached Superior with the idea of throwing Spaccarotella the new carb curveball, the company agreed to the story. Its employees have confidence in their man and know he will deliver. We wanted new baseline figures before the carburetor was modified and then a second session on the Dynojet to measure the result. To eliminate as many variables as possible, our test used the same Dynojet on the same day, with the same operator. Much of what Spaccarotella does is confidential, but if you send Superior your carb, the company can modify it, new or used.

Follow us to the Dynojet at Superior to see if Spaccarotella can squeak a few more ponies out of a new carb.

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Here are the results of the best baseline pull. Our Windsor uses the stock crank and displacement. So with 274.83 hp at 5,100 rpm and a torque reading of 311.99 lb-ft at 3,700 rpm, these numbers are pretty respectable for a street-driven daily driver. The graph contains the same information as the numerical tables, however, certain parts (such as the substantial dip in both horsepower and torque at 4,350 rpm) become more evident on a graph.
RPM HP TQ
2,800 144.91 271.80
2,900 155.99 284.30
3,000 166.82 292.05
3,100 175.73 299.41
3,200 185.15 305.52
3,300 193.20 307.48
3,400 200.70 310.03
3,500 206.77 310.28
3,600 218.60 311.63
3,700 219.79 311.99
3,800 226.26 311.34
3,900 229.64 309.26
4,000 234.82 308.33
4,100 233.51 305.53
4,200 243.28 304.23
4,300 247.18 301.92
4,400 250.03 298.44
4,500 254.66 297.22
4,600 254.66 290.76
4,700 257.52 287.77
4,800 260.79 285.36
4,900 263.35 287.53
5,000 272.18 285.90
5,100 274.83 283.03

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The numbers tell the tale. The Dynojet recorded a peak horsepower figure of 289.48, an increase of 14.65 hp. The 322.69 lb-ft reading is also a substantial improvement, amounting to 10.70 lb-ft. Here's the chart for the final pull. Although the dip at 4,350 rpm has smoothed out, another smaller bump has emerged right above 4,600 rpm, necessitating a few additional tweaks from Spaccarotella to eliminate it. With a gain of more than 14 hp, accompanied by a 10.7 lb-ft improvement in torque, the Superior carburetor hop-up is a resounding success that you'll notice right away and feel through the seat of your pants.
RPM HP TQ
2,800 152.30 285.69
2,900 163.15 295.48
3,000 170.56 298.60
3,100 181.43 307.38
3,200 189.66 311.28
3,300 193.06 317.81
3,400 205.74 317.81
3,500 212.66 319.12
3,600 220.02 320.99
3,700 227.33 322.69
3,800 232.87 321.86
3,900 237.50 319.85
4,000 243.43 319.62
4,100 245.84 315.57
4,200 250.25 312.93
4,300 255.85 312.50
4,400 259.06 309.23
4,500 259.18 302.50
4,600 264.33 301.81
4,700 263.62 300.18
4,800 275.27 301.20
4,900 277.63 297.58
5,000 283.13 297.41
5,100 287.16 295.72
5,200 289.48 292.38

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