Shawn Byrne / Treasure Island, FL
Go to YouTube and search "Shawn Byrne's Turbo Mustang." You'll find a cool, multi-angle video of him making an 8.420-second pass at Bradenton Motorsports Park, with a trap speed of 133 mph. Using our trusty Car Math iPhone app, that speed, plus a race weight of 3,270 pounds, means Shawn's car is making somewhere in the neighborhood of 1,100 hp at the wheels. We met Shawn at Lights Out V, the Outlaw Drag Radial race at South Georgia Motorsports Park, where he was competing in the Ultimate Street Class. We did a double take upon seeing the distinctive valve covers of a 2-valve mod motor. Shawn says the car is capable of breaking into the 7s in the quarter-mile and claims his '99 Mustang is the fastest 2V car out there right now. What's it take to make this kind of power with the lowly 2V engine? Lets explore.
The engine runs on FAST's XIM engine management system with MSD's DIS 4 ignition box controlling stock Motorcraft coils.
We've said it before: To make big power, you need good cylinder heads. Billet cranks and pistons don't make horsepower if air can't get into or out of the engine efficiently. For this application, there's no way the stock 2V cylinder heads were going to be able to support this much horsepower, no matter how much boost you put to them. They simply weren't designed for something like this, so Shawn wisely stepped up to a pair of Trick Flow Specialties Track Heat heads. The combination of more efficient ports and runners and revised valve angles in a better combustion chamber make these heads a logical choice for making serious horsepower.
Able to ingest small children, Shawn's CRT S400 80mm turbocharger is basically what made us stop to look at his car in the first place. Yes, we admit that was shallow of us. Shawn limits the boost to a rather conservative 21 psi. Want one of these for your car? Go to www.Stores.CustomRacingTurbos.com
Shawn and his buddies made the sheetmetal intake manifold. They added the reinforcement ribs because the previous version broke under boost. Missing at the time we took this picture is the inlet plumbing coming from the air-to-water intercooler mounted behind the passenger-side headlight.
One criticism always levied against Ford's modular engines is lack of displacement. The 4.6L is the most common and is found in passenger cars and 1⁄2-ton trucks, while 5.4L engines are found in 3⁄4- and 1-ton trucks, Navigators, some HiPo Mustangs, and the GT supercar. Converting from liters, these engines measure 281 and 330 ci, respectively, so they're displacement-challenged compared to most pushrod small-blocks built these days. Therefore, if your plan is to make maximum power with one of these engines, it only makes sense to start with a 5.4, like Shawn did. His is an aluminum block from a GT, which he had bored and sleeved to 358 inches. The rotating assembly consists of the crankshaft from a Lightning pickup, Manley connecting rods, and Diamond pistons.