2007 Mustang GT - Tripping The Light Camtastic

Horse Sense: As its name suggests, Big 3 Performance works its magic not only on Mustangs, but also on Mopar and GM muscle. Yes, I know the phrase "GM muscle" is pretty much an oxymoron. (Just kidding, Dr. Meyer.)

Around here, we catch the keys to a fairly broad array of certifiably banzai Mustang machinery, often revved-up by some form of power adder. In truth, we get used to it, so when I got the call to photograph and drive this tastefully understated Paxton Novi 2200-blown S197 from Big 3 Performance (www.big3 performance.com), my seat-of-the-pants dyno knew what to expect-or so I thought.

The first clue that I had sadly underestimated this experience came from simply listening to-and feeling-this thing idle. It has a deliciously nervous and lumpy cam lope that's reminiscent of something more like a late-'60s big-block drag car. A Three-Valve modular isn't supposed to create its own little earthquake, not even one bored and stroked to 5.0 liters of displacement. And yes, the plug wires were all attached.

It's no secret that centrifugal-blown cars are rpm-reliant when it comes to boost, so they're usually relatively docile down low on the tach. This is especially true if boost-friendly, lower-compression pistons have been substituted, such as the 8.7:1 Arias units working with the Eagle stroker crank inside this '07 GT's bored stock block. Believe it when I say that such soft throttle response is not an issue with Big 3's manic GT, which is simply called the Stroker Edition. This thing has a hair trigger unlike anything I've ever experienced in a modular Mustang of any variety. The initial throttle response is so immediate-no, make that violent-that it's all but impossible to tame, at least without a lot more seat time than I had. In traffic, the only sane practice is to desperately short-shift and get it up into Third gear ASAP. Big 3's sales manager, Anthony Stephenson, tells us that this berserk off-idle response, as well as the fact that the 5.0-liter missile will zing happily and repeatedly to 7,500 rpm, is in great part due to its custom-spec Crower cams.

Forced induction doesn't normally need or even like big cams. However, Anthony says that even with the Novi huffing out 18 psi of boost prior to fitment of these bellicose bumpsticks, the Stroker's rear-wheel horsepower was "only" in the 530 vicinity, whereas now, the Dynojet rollers-or any handy pavement-are subjected to a full 631-rwhp wallop, which is impressive for otherwise bone-stock heads. This, by the way, is on 93-octane pump gas, which we confirmed by fueling up the Stroker before heading out to try and lose our license in Dearborn's rush hour traffic.

If all this sounds interesting, our tester is actually the prototype for a series of 20 such Strokers that Big 3 Performance wants to build. While this one has a stock-style, five-speed Tremec 3650 with cryogenically treated gears, the production cars will carry six-speed TR6060s and utilize a SPEC Super Twin twin-disc clutch and a full 3-inch exhaust in place of this car's 2 1/2-inch tubes. Oh, and CNC-ported heads-as if it needed more power.

It's not all about power. Anthony tells us this car is now owned by Michael Zamzow, who chose it because of his apparent affection for hot-lapping at Wisconsin's Road America track. Therefore, the Stroker's drivetrain, suspension, and brake modifications (see our 5.0 Tech Specs sidebar) are just as important to him as having 631 hp on tap. We're still trying to get our minds around some sort of corner-exit strategy with this monster's light-switch throttle response. Obviously, Michael has much better reflexes than I do.

For that track role, or even spirited street use, the Stroker's suede seat inserts are also a wise and stylish way to stay in place under lateral g-loading. We can't help but think that the Hurst shifter, with its retro white knob, is the perfect complement to the Stroker's old-school, rock-and-roll cams. The dash plaque proudly declaring this a Stroker Limited Edition matches those discreetly placed mid-stripe on the front fenders.