2005 Mustang GT

It's still a bit disconcerting. From a few feet away, it has the looks of a new Mustang. Sure, it has some wheels on it, and are those Shelby body parts? Windveil Blue wasn't a GT 500 color, but then again, we know exactly what this car is. It's the normal people that seem taken aback by Don Walker's 810hp '05 Mustang GT. When he turns the key, it sounds anything but stock as the built Three-Valve rumbles to life and the familiar buzzing whirr of a ProCharger floats atop the syncopating rhythm of custom Crane cams and competes with the rumble of MAC Prochambers to become the star of this sonic show. All the glorious sounds of performance announce the potential of this modern hot rod.

I jump in the passenger seat and we head to our photo location. Don drives normally at first, but he can't resist showing me how this car will annihilate the tire at the slightest urging. Whether we are cruising or hot-dogging, heads turn everywhere we go. It's not a long drive, but people working alongside the road or driving on it can't help but give the 'Stang a second or third look. The most recent Mustang is a head turner off the lot, but this one is different. The looks are there, but the sound is what first attracts the attention. At a second glance, on-lookers try to process the seeming contradiction of the modern appearance with the retro hot-rod sound. In a way, that was what Don was after.

Besides wanting to build a way-cool S197 with huge power, Don had ulterior motives. He has a shop called Modular Madness [(941) 527-0156; www.modularmadness.com] in Sarasota, Florida. Starting to make sense, right? While it takes a mad scientist to turn a brand-new Mustang into a fire-breathing, 810hp monster, it also takes talent to build one that starts right up, idles steadily-even with the air on-and retains all the creature comforts. That's what Don wants you to know about, and we can't blame him. We surely want to know how he did it.

Like most project cars, it didn't start with such a radical concept. Don began working with his old friend Jim Summers at ProCharger to push the stock Three-Valve to the limit. Happy to oblige, Don kept tuning and boosting his stock motor with long-tube headers until he found the limit at 577 hp with a D-1SC supercharger. Finally, some rods let go-OK, all of them let go. After 200 dyno pulls and numerous dragstrip passes, destruction ensued, and Don was in need of a new engine. As you all know, you might as well build it to the hilt, and that's what he did. "I built a motor to showcase my product, and I tried anything new that was available."

What might surprise you is he kept the factory aluminum block. Apparently, the block in the latest Mustang is one of the strongest modular blocks to date. Don chose the tried-and-true Terminator-forged crankshaft and topped it off with Manley H-beam rods and JE pistons with 17cc dishes. He assembled the engine, but relied on the porting talents of Dan Rawls and the valve job tricks of Herb Yancer to expand the potential of the stock Three-Valve heads. Custom Crane cams control the valve events and retain the use of the factory variable cam timing mechanism. Thus far, Don hasn't deviated from the factory VCT programming, but he thinks there's some power in there.

This car isn't all about power, however. Don still drives it on the street, and for that you have to hand it to the collaborative tuning efforts of Don and DiabloSport's Kevin McDonald. As we mentioned, the car fires right up and idles like a purring kitten despite its radical mods. Don keeps chipping away at the tuning. When we experienced the car, it was "only" making 760 rear-wheel horsepower, as the 60-lb/hr injectors were at their limit. Larger 83-lb/hr injectors were the answer, but feeding either set with a stock-style returnless arrangement meant stepping up to twin Ford GT fuel pumps, a larger -8 fuel line, and voluminous CPR billet fuel rails. Don tried several combinations, including using pumps from the GT 500, but those signed off around 600 hp. That should be helpful news for GT 500 owners looking to push big power.