Without a doubt, the '05 Mustang is slated to become a classic in terms of both styling and performance. Yeah, we've heard it all before, but this car never ceases to garner attention, whether cruising down Main Street or proudly parked curbside. The ads featuring the digital ghost of Steve McQueen aptly summed it up, "If you build it, they will come." And they have--right into the dealership.
For some of us who are old school in terms of building horsepower, hopping up a late-model car with all of its gizmos and New-Age controls can be a daunting task. Truth be told, the reason that all these cars get such good mileage while still being capable of blistering the quarter-mile is due to computer science. Sensors and computer code allow the car to automatically react to different circumstances and conditions, reading factors like air speed through the intake inlet above the throttle body and exhaust heat, then instantly changing settings for camshaft advance, ignition timing, and other components based on that data. Unlike in the old days, if you make a big hardware change, the car may not run as well or go as fast as it did stock. You need to reconfigure the computer to adjust to the new environmental conditions surrounding the engine's computer-driven responses.
However, because of this computer science, it is also now possible to build fresh horsepower without ever lifting a wrench. In the past, an aftermarket chip was a big part of this; just put a new chip in place of the factory unit. Nevertheless, the new Mustang does not have provisions for a removable chip; changes need to be made to the factory computer software by reflashing (reprogramming) a new tune into the stock computer. This is where DiabloSport's latest version of the Predator comes in.
Based in Boca Raton, Florida, DiabloSport has been a leading player in the OEM computer reprogramming business for several years, building products like the custom Delta Chip burner, the diesel-based Power Puck, and the DiabloSport Predator tool seen in our story. Since 1992, these guys have reworked OEM electronic products for many automotive applications. DiabloSport was founded to service the American performance industry in 2000. For the '05 Mustang, the company sells a pre-programmed "flash tuner" unit (PN U7140) that allows for both quick tuneability and ease of installation; the Predator uses your car's battery power, is plugged directly into the OBD-II port under the dash, and can install a hotter tune in less than 10 minutes. It also adjusts the transmission computer, as well.
By installing this program into your new Mustang rather then swapping in fresh hardware, the DiabloSport Predator lets you have your cake and eat it. The performance code is not permanent, and with the click-through menus in the DiabloSport Predator's LCD screen, it is a simple task to reinstall the factory program if the car needs to be base-lined or go in for service.
How Does It Work?
The code that DiabloSport's engineers have written adjusts various engine management parameters to increase performance while keeping fuel economy in mind. The DiabloSport Predator will first retrieve a copy of the stock vehicle computer program from your car and use data from it to lock itself to that specific computer. This is required because the DiabloSport Predator performance tunes you get with the tool are written and saved as difference files; these files use the stock computer program you just downloaded, apply performance-related overwrites to it, and then re-flashes that adjusted program back into the vehicle computer.
For this reason, your Diablosport Predator can only be used in one car unless you restore the copy of the stock program back to the car's computer. You can then use it in another vehicle with a fresh stock computer download. We will note here that while many of these adjustments are within the realm of most emissions standards, they are not approved by CARB for highway use in sunny California.
The OBDII port is located under the dash and is easily accessible; this is where the dealership service department also plugs in its diagnostic equipment. The DiabloSport Predator is plugged in and will begin by giving basic info and a disclaimer (mainly because this product will disable the rev-limiter in the 4.6-mod motor--programmed at the factory for an anemic 5,650 rpm). After entering the initial data, including a VIN code so it is for your car alone, it will ask you which tune you want to install: the 87-octane performance tune, the 91-octane performance tune, the 93-octane performance, or the stock tune you started with. There is even room for up to five custom tunes if the car has been uniquely or extensively modified; these special tunes can be custom-made by any of the 170 ChipMaster Revolution dealers nationwide.
As you click through each question, the LCD screen will track the progress of the unit. You will know the factory tune is being downloaded into the DiabloSport Predator when it asks you if you want to modify the tune or install it. For this test we simply modified for the 93-octane tune and then installed it with no changes. Using a bar graph similar to what you may see when doing updates on your home computer, the LCD showed us that the tool was creating the new tune, and then showed us it was being installed.
For our test, we used the load-bearing Superflow dyno at the DiabloSport research and engineering facility. The only modifications to the three-week-old test car were a fiberglass hood, better rubber, and a cat-back exhaust; it was stock under the hood. The numbers above are corrected to represent SAE Dynojet numbers and all of the runs were made at the same exact temperatures.
But Wait, There's More...
You've got the new tune in and you're enjoying that feel in the seat of your pants, but you would like to do some more tweaking on the package. Unlike other flash tuners, the DiabloSport Predator does not simply stop at reprogramming the factory computer, it can also be used to make incremental adjustments.Plug your DiabloSport Predator back into the OBDII port, click through the data questions, and you can begin to modify it by advancing the timing, adding more fuel to the injectors, and other changes. Using the software, you are allowed to adjust the already scienced-out DiabloSport parameters by as much as 10 percent. Once you've made your changes, click through to install the changes and within five minutes you have got your new adjustments in the car, and you never even opened the hood.
Of course, being hot rodders, a little too much may be a problem, especially if making several changes at once. In case you get really lost, plug in the DiabloSport Predator and reinstall the stock tune once again to bring everything back to zero and start over from scratch. That is the true beauty of this unit; you have very little chance of making any change to the car's computer permanent.
Let's go one step further. Let's say you want to add a cold-air kit from Steeda. This is going to make readings through the MAF (Mass Airflow) sensor much different from stock, which can throw the stock computer program into chaos. DiabloSport has worked closely with Steeda and other aftermarket suppliers to have tunes ready for these changes . A few of the most common parts changes come pre-installed in the DiabloSport Predator; simply click through and add the parts to the tune you are installing.
Others are being added at the company's website www.diablosport.com on a continual basis; any of these can be downloaded free of charge from the Web site into your Predator using a standard serial cable, then installed into your car. It is as easy as it sounds. As mentioned earlier, the company's 170 ChipMaster Revolution dealers can also create custom programs if you have made unique adjustments.

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 This is the DiabloSport Predator....  This is the DiabloSport Predator. It consists of the tool and cable going into the 2005 Mustang OBDII port, a detailed booklet with step-by-step instructions, and a decal. List price is $399. |
 Up on the dyno for the pulls,...  Up on the dyno for the pulls, we got the car to hit 285 hp stock by removing the rev-limiter from the computer. By simply removing the inlet hydro-carbon filter and adding the 93-octane tune, we peaked just below 300 hp at 298.4 at 5,900 rpm, but the car then made over 290 hp from 5,100 to 6,300 rpm, a huge 1,200-rpm power band. Torque peaked at a stump-pulling 312 lb-ft. |
 This is the OBD-II port located...  This is the OBD-II port located under the dash. Simply plug in the DiabloSport Predator and follow the instructions onthe LCD screen. |
 Here is the tuner in action....  Here is the tuner in action. Each step will ask for a response, and upload/download progress is displayed and tracked via a horizontal bar graph on the LCD screen. The keypad can also be used to make adjustments to the DiabloSport pre-programmed tune files. |
 Stock 285.5 hp/292.5 lb-ft...  Stock 285.5 hp/292.5 lb-ft For the most part, the stock tune was crippled by the rev limiter; at 5,700 rpm, the car went into retard mode and power fell to nothing. So for this test, we went in with the DiabloSport Predator and removed only the rev-limiter from the computer. The end result of three pulls found us with a best result of 285.5 horses at 5,500 rpm (and 280 horses or better from 5,300 to 6,100 rpm) and a max of 292.5 lb-ft of torque at 4,500. |
 87-Octane Tune 293.8 hp/305.6...  87-Octane Tune 293.8 hp/305.6 lb-ft After a brief cool-down period, we installed the new tune and did three more pulls. Right away, the exhaust sounded crisper, and the engine pulled hard all the way to 6,400 rpm with no problems. Looking at the data, the 4.6 mill not only made more horsepower, but it also pulled much harder through the top of each gear with little fall-off as the engine topped 6,000 rpm. Our max torque was up by 13 lb-ft (305.6 at 4,500 rpm) and our horsepower hit 293.8 at 5,900 rpm, but the powerband was a lot wider. In fact, the car made 280 horses or better at the rear wheels from 4,900 rpm up, and was at 290.5 by 5,300, and stayed that high or better until the pull was almost done at 6,300. Regardless of the tune installed, engine speed this fast should only be done with high-test gas to prevent detonation issues above 6,000 rpm. |