Callaway revealed new GBB Epic and Epic Sub Zero drivers for 2017.
Over the years we've seen lots of ways to make drivers hotter – from face cups to elliptical sweetspots, speed slots to inverted cones. But we've never seen anything like the tech on Callaway's new Epic driver and there's a low-spin Sub Zero version.
Callaway GBB Epic Driver
The club changes the way the head and face behave to boost ball speed, using a sophisticated titanium/carbon body and two titanium bars behind the face to stiffen the entire structure.
The key structural components of a driver – crown, sole and face – all bend, flex and rebound when they hit the ball. As they're connected, they influence each other's dynamics. So "Jailbreak Technology" makes the face more efficient by focusing energy back into the ball. Boffins call it "energy lensing".
Jailbreak uses two very light (3g), but very strong titanium, bars right behind the face, parallel to each other and connected on either end to the crown and sole. The size, strength and position of each bar works together to reduce how much the crown and sole deflect, allowing the face to take on more of the load.
Is it said to result in faster ball speeds across a larger area of the face, to promote more average distance from swing to swing. Extensive player testing confirms that Jailbreak Technology significantly boosts ball speed.
We saw it with our own eyes when Callaway's European Tour star Sebastien Gros – the second longest hitter on tour in 2016 – tried the Epic for the first time; he gained 3mph on his XR 16 after putting a head on his own shaft.
It's not just about the bars, though. Epic's clubhead consists of a new aerospace-grade titanium Exo-cage construction, with crown and sole panels made of triaxial carbon – a very light and strong composite material used in the new Fusion driver.
Nearly half of the head's surface – 46% – is made up of this carbon. With the crown weighing just 9.7g and the sole just 5.8g, it's the lightest crown ever in a Callaway driver.
Hocknell and his team weren't finished there, though. They added adjustable perimeter weighting (with a heavier weight on a redesigned track) to offer up to 21 yards of shot-shape correction (22% more than the Great Big Bertha) to dial in straighter shots.
Hocknell told TG: "We paid particular attention to the shape, aesthetics and acoustics to make Epic pleasing to the eye and the ear. The Tour-inspired shape is sleek, aerodynamic and confidence-inspiring.
The triaxial carbon weave visible on the rear half of the crown, along with the vibrant green highlights, gives Epic a uniquely pleasing appearance."
Epic details: RRP £469. Lofts: 9.5°, 10.5° and 13.5°HT. Left hand in 9°, 10.5° and in 13.5°HT as custom only. On sale January 27.
Those two vertical bars behind the face link the crown with the sole to increases distance by stiffening the body, transferring more energy to the ball.
The head is made from an aerospace-grade titanium "exo-cage"; an an ultra-light triaxial carbon crown (9.7g, the lightest ever in a Callaway driver) and sole (5.8g) allows designers to move more weight into the perimeter for higher MOI and more forgiveness.
Changing the position of the 17g weight on the track gives 21 yards of shot-shaping control to promote straighter and longer tee shots.
Like the XR 16, the streamlined head has a Speed Step –created with input from Boeing – to improve airflow for more speed and distance without extra effort.
Four shaft options
HZRDS, Diamana, Fuji, and Rogue in four weight classes: 40g, 50g, 60g, 70g. Each premium, Tour-proven shaft is engineered to promote speed, stability, feel and control.
Callaway GBB Epic Sub Zero Driver
Callaway designed the Epic Sub Zero as a powerful, low-spinning Tour-level driver that would be popular among its superstar players. But it's so forgiving, it's perfectly suited to mere mortals. Callaway says it is the most forgiving pro-style driver they've ever made.
Like the "standard" Epic driver, it has titanium bars behind the face to increase ball speed, and a super-light titanium-carbon head.
But unlike the other model, it doesn't have an adjustable weight track (better players generally don't need any help to hit it straighter).
Instead, it has two interchangeable weights (12g and 2g) in the sole at the front and back, to let you adjust the spin-rate by up to 250 rpm (according to robot testing), the launch angle and even MOI. The heavier weight forward lowers spin; installing it in the back increases forgiveness and promotes higher launch.
Callaway says with the 12g weight in the rear position the Sub Zero's MOI measurement is 42% higher than Big Bertha 816. Head speed gets an aero boost from Callaway's Speed Step crown design.
Epic Sub Zero details: RRP £469. Lofts: 9° and 10.5°. Left hand option available in 9° and in 10.5° as custom only. Stock shafts HZRDS, Diamana, Fuji, and Rogue in four weight classes: 40g, 50g, 60g, 70g.
Two interchangeable weights (12g and 2g) positioned in the sole at the front and back, gives the player the ability to adjust the spin-rate plus or minus 250rpm.
Why is it called Sub Zero?
It's in reference to the centre of gravity location – low and deep – which promotes a high launch angle and lower spin rates.
The key numbers
460cc Head size
45.5 Shaft length
469 Recommended retail price (£)
3 The weight of one of the titanium Jailbreak bars (g)
21 Yards of shot shape correction from the adjustable weight track
46 Per cent of the head made from triaxial carbon fibre
9.7 The weight of the crown (g), the lightest ever in a Callaway driver)