Geometric drivers dominate PGA Merchandise Show

	Tiger Woods uses Nike's Sumo driver, which is part of the geometric revolution. AFP/Getty Images
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We have seen the future of golf and it is ... square?

Yes, that is a bit of a surprise, but that's what I learned, among other things, at the recent PGA Merchandise Show in Orlando, Fla. In the quest to build a better club (technically, the quest to sell a lot more of the better clubs than the other guys), equipment makers turned geometric drivers into the hot ticket of 2007.

Geometric drivers? Clubs have taken on different shapes -- squarish, rectangular and even triangular -- as equipment companies try to improve their clubs' moment of inertia (MOI). (That's technospeak for a club's resistance to twisting.) The less a club twists before impact, the more stable it is. And, therefore, the straighter and farther the shot flies. Clubmakers are already near the limits the USGA has set in other categories -- coefficient of restitution (resiliency), length (48 inches) and size (460 cc). They still have some space on the new MOI limit -- 5,900 grams/centimeter². Until this year, few drivers cracked the 4,000 MOI barrier. The new models, depending on who's doing the testing, are pushing 5,000 and maybe even clearing it by a bit.

All you need to know is that to maximize MOI, clubmakers are moving mass around to get more of it behind the sweet spot.

"The USGA gives you a five-inch-by-five-inch box in which your profile needs to fit," said Chris McGinley, an engineer for Titleist. "Everyone is trying to stretch their geometry in those limits. That's the new area the USGA has given us to chase. We're all trying to get up in MOI, it's just a matter of how much we can improve. I don't think you'll see big, sweeping jumps in improvement like before. Improvement now will probably be more incremental."

It's a fast-changing world out there in golf equipment. Here are some of the things I saw at the PGA Merchandise Show (unfortunately, I didn't have time to try out every single new club), along with a few things that weren't at the show:

Geometric drivers

Nike Sumo2 ($479): This is the brother for Nike's popular SasQuatch model. It's big and squarish and makes a harsh, metallic sound at impact. However, three of the four swings I made with it at Demo Day were absolute nuke-jobs. I'm willing to overlook a little noise pollution for results.

Titleist 907 D1 ($500): This driver is semi-triangular in shape and pretty hot. I played a round with it after the show in 30 mph winds and hit it pretty straight, just as advertised.

Callaway Ft-i ($625): It's duly square when seen from above. Its sole is uniquely humped. I think it looks futuristic. My boss totally killed it when he tried it ...

TaylorMade Burner ($360): This club makes up for a light grip and shaft by being an inch longer in the quest for distance. The ball really seemed to jump off its face. I couldn't find anyone who tried it and wasn't enthused.

The Cobra Speed LD ($375): This driver has an elongated head and has a clangy sound at impact, sort of like the Sumo, but it goes.

Orlimar Fury QB ($299): This is another square-headed driver in the geometric race, but I didn't get to hit balls with one.

Simpac 460 cc-driver ($549): Little-known in the U.S., Simpac offers a decent square-headed 460 cc-driver with multi-colored heads. It also has square fairway woods with small heads that were remarkably easy to hit. If you can find them, they're worth checking out.