Tom Wilson
October 5, 2006
Bolt-ons, a chassis dyno, and a V-6 Mustang are a perfect fit. Thecurrent 4.0-liter V-6 has the smoothness and punch to make it as a dailydriver. And with a few easy mods you can have 20 more horsepower.

Horse Sense: East and West Coast readers are often left wondering abouteach other's octane. That's because East Coast premium is typically 93octane, while West Coast premium is only 91 octane. For bolt-on carssuch as the one tested here, it doesn't matter, but East Coast blowercars can often eke out a little more horsepower on pump gas.

If you're a senior Mustang enthusiast--not to mention a plain, old seniorlike some of us--today's 4.0-liter V-6 Mustangs are especially wonderful.For decades, the entry-level Mustang has made do with either hopelesslyoutclassed four-cylinder or fairly agricultural V-6 engines. The resulthas been a justly earned "V-8 or bust" attitude in the Mustang ranks.

But now, that's a shame, as today's smooth, revvy 4.0-liter SOHC bentsix is a great fit for daily duty Mustangs. Its advantages areimpressive. Not the least, the V-6 is considerably less expensive. It'sless expensive to purchase, less expensive to fuel, less expensive toinsure, and maybe even less expensive to keep tires and brakes due toless weight.

Here's the full monty: C&L's cold air intake and pre-programmed Predatoroption. GTR offers this complete kit for $614.99, which includeseverything shown. If you already have a Diablo Predator, the C&L intakekit is $284.99 by itself. Another option if you don't have a Predator,is to purchase the C&L intake kit by itself and continue to run the caron 87 octane fuel. It's a smaller power gain, but less money, too.

Give the V-6 Mustangs the top score in front-end weight and overallchassis balance, and there's no contest when it comes to working roomunder the hood. The V-6 looks great and can be purchased with a manualtransmission. Not only that, but all of the chassis mods that work sowell for V-8s work even better on the lighter, better balanced V-6s.

Of course, the V-6 doesn't sound like a V-8, doesn't have as many speedparts available as a V-8, and just doesn't have the power potential ofthe V-8. If it's rippling masses of V-8 power you want, then sell theV-6 and get a V-8. There's no replacement for displacement.

But there are many of us who don't need all the rippling mass of V-8power. Most of us aren't sparking up their household's second Mustang,or simply can't swing the money a GT requires. For those so inclined,there are V-6 bolt-ons. Bolt-ons make good sense for the 4.0-liter V-6Mustang. If it's big speed you want, get a V-8 and go crazy, but don'twaste time trying to make a 4.0-liter V-6 respond like a 4.6-liter V-8.It can be done, but at major cost. Just ask the Europeans.

The V-6 is a great real-world car, and bolt-ons retain the highlydesirable man-about-town persona while giving that little more urgeeveryone wants.

So, this story is all about the real and practical V-6 bolt-on. To seewhat was up in this corner of the Mustang market, we asked Ricardo andGonzolo Topete at GTR what pieces their V-6 customers were buying. GTRmails large volumes of mild-to-wild Mustang parts, and recently openedan installation center with dyno services. Now, they know what'sactually going on the new 4.0-liter cars.

It turns out to be a short list: cold-air intakes, mufflers, andunderdrive crank pulleys. Additionally, we wanted to see if the new V-6engines responded as favorably to octane increases the same way the V-8engines do. So GTR scheduled a customer's five-speed,manual-transmission '06 Mustang for some bolt-on work. We brought thecamera.

One thing we noticed immediately is the ample elbow room surrounding theV-6. Considering the six has only 600 cc less displacement than theThree-Valve V-8, or a massive Four-Valve Shelby 5.4 for that matter, thespacious working conditions are impressive and appreciated.

We'll also note the 4.0-liter V-6 uses cast-iron exhaust manifolds. Theengineers tell us the massive castings help with emissions (it keepsheat in the cats), but they'll also end any worries about headercracking. That is an issue with '99-'04 Mustang V-6 passenger-sideheaders ('96-'98 V-6 cars do the same thing, but not quite as often)when air-conditioning condensation water drips onto the header andcracks it. That won't happen with the new car. The cast-iron manifoldsappear reasonably shaped from a flow standpoint, too. They probablydon't hurt power much.