Titleist GT drivers: What you need to know

WHAT YOU NEED TO KNOW: The three new Titleist GT drivers (GT2, GT3, GT4) fill similar slots to the three TSR models they replace with the forgiving GT2, the shot-shaping GT3 and the ultra low-spin GT4. But they do so in a dramatically new way for the traditional Titleist metalwood philosophy. For the first time these streamlined designs feature a super lightweight thermoplastic polymer piece that overlaps the crown and joins to the sole on both the heel and toe sides. This weight savings creates a combination of forgiving rear weighting with forward mass to lower the center of gravity for better energy transfer.

PRICE: $650 (GT2, GT3: 8, 9, 10, 11 degrees; GT4: 8, 9, 10 degrees). At retail Aug. 23.

3 COOL THINGS

1. The shape of speed. Every driver introduction in recent memory is going to make a reference to speed. Typically, that reference is about creating ball speed, and the new GT family of Titleist drivers is, of course, doing that with an enhanced version of the variable face thickness design that was ushered in two years ago with the TSR family of drivers. More on the face in a bit, but Titleist’s first order of business with this new family of drivers this go-round started with aerodynamic shaping designed to boost clubhead speed. And as we all know, more clubhead speed is the foundation for more ball speed.

If you look at these models from the side, particularly the meat-of-the-market GT2 (above) and GT3 (below), you will see sleeker lines, softer curves and a raised aft section, a key to reduce the head’s turbulence in the air. It can be a bonus boost to the faster swingers, but don’t discount the ease through the air more average speeds can experience, too, said Stephanie Luttrell, Titleist’s director of metalwood product development. The key is focusing on a shape more like something designed to really fly through the air.

“Part of what we've learned is that if you think of the clubhead almost like an airplane wing, you want to see the back of the clubhead come together at more consistent aperture rates and more consistent angles of closure,” she said. “When we shaped it like the wing of an airplane, you're able to then keep the flow of air connected to the crown and the sole and you don't get turbulent eddies and separation. You’re able to minimize drag and increase clubhead speed.

“Anything that we can do to produce more speed for players through clubhead aerodynamics, it benefits the fastest players obviously the most, but it benefits all players at incremental levels.”

That enhanced effect on clubhead speed is fundamental, but to get to the next level, it needs a responsive face design, as well. The GT drivers feature a face design that incorporates a thicker ring shape around the perimeter of the back of the face, while the middle of the face inside that ring uses a variable thickness pattern to maximize deflection. The face thickness changes from as much as four millimeters thick to as little as two.

“That thickened band allows us to constrain the face perimeter,” Luttrell said. “And it brings more localized deflection to face center, delivering maximum ball speed on center, but also ball speed consistency on those off-center hits.”

2. A new age in materials. The problem with a focus on aerodynamic shaping in a driver is how much it runs at cross purposes to a functional shape for forgiveness and lower spin. Raising the back end of a driver may make it move easier through the air, but it also raises the center of gravity. That produces shots that don’t launch high enough and shots that feature excess, distance-robbing spin. That’s especially if you make drivers the way Titleist traditionally has with an all-titanium construction.

But not anymore.

The GT drivers usher in a new materials age for Titleist thanks to a distinctive (but relatively undetected) crown piece made of a lightweight thermoplastic polymer. The piece, which wraps around the crown and down to the sole on either side of the head, is made of carbon fiber impregnated with a polymer resin that “actually conducts sound frequency,” Luttrell said of the substance, which is one-third the mass of the surrounding titanium. “That resin allows us to tune the product to sound and feel.”

But it’s the weight savings that is the real game-changer for the GT designs. The crown wrap piece provides saved discretionary mass that’s divided internally between the back of the club (for stability) and the front. That front location that lowers the center of gravity significantly, putting it more in a direct line with the center of the face, what’s generally referred to as the neutral axis. This is an imaginary line that’s perpendicular to the face and running through the center into the head. A center of gravity close to that line provides low spin and the most efficient energy transfer for both center and off-center impacts, Luttrell said. It also helps how efficiently the crown wrap piece has been bonded to the titanium body.

“The way we've been able to optimize the positions of these joint ledges and bonds is allowing us to distribute the mass exactly where we want it and allowing us to then be able to hit our center of gravity goals,” she said.

3. Making the case for less is more. While there has been in some circles a push toward driver designs lately with an extreme moment of inertia, including those that push a combined stability in the horizontal and vertical planes above the 10,000 grams-centimeters squared mark, Titleist’s GT driver philosophy is decidedly not in that camp. These latest models, with a more forward and lower CG, actually show a slightly lower moment of inertia than their predecessors. That’s an immaterial concession, Luttrell said flatly.

“When you focus solely on one parameter, it can oftentimes be at the detriment of other aspects of club performance,” she said. “Moment of inertia is logarithmic in terms of its benefit, and so the higher that you get, the less impactful it is to you. So where these products all live is still in a space that's incredibly stable for launch and spin stability, as well as speed stability.”

Translation: Super high MOI, in Titleist’s design brief, compromises overall performance. Moreover, the company points to research that indicates 85 percent of all driver impacts occur within a half-inch of the center of the face, a region she says isn’t going to be improved by super-high MOI designs.

“As you seek to design for moment of inertia, there are penalties for seeking out that max inertia,” Luttrell said. “You lose speed because of your center gravity position, because of its depth. Do you want to design a driver to be as fast and as great performing as you can for 85 percent of the time? Or do you want to design it for the 15 percent of the time and sacrifice the 85 percent?”

Instead, the GT lineup focuses on designs that cater to specific player types. The GT2 is the larger footprint more forgiving model with higher launch. The GT3 features a more forward CG location with a movable track that’s now forward in the sole compared to the TSR3’s rearward track (but similar to the track found on the TSR3 fairway wood). The GT4 is the spin-killing model but also features 11-gram and 3-gram weights that can be arranged to create a more forgiving design when the 11-gram weight is put in the rear port. For all models, the lower and more forward CG keys overall better performance, Luttrell said.

“We know by getting that CG closer to the neutral axis it helps with momentum and the physics of the impact for unlocking more speed,” she said. “But it also helps with our goals of generating a better spin to launch ratio. It gets us higher launch, lower spin, or higher launch, same spin.”