Driver: Persimmon V Steel V Titanium

How much has Driver Technology moved on?

The persimmon was the driver of choice up until the late 80's early 90s, Bernhard Langer was the last golfer to win a major with one in 1993. The Taylormade steel driver first made an appearance in 1979 and the burner model was in play until 1993. The first titanium driver was the Callaway Great Big Bertha in 1996 and the current 460 cc titanium haven't changed that much since 2005/2006 What is the difference between these clubs and a current titanium driver?

How much better is the current driver and why is it better?

 

A couple of days ago we put this to the test. We tested three drivers, a Titleist Tour Model Persimmon, A Taylor Made Burner Steel and a PXG 0811 Titanium.

 

 The specifications of each club were

 

 

Club	Persimmon	Steel	Titanium
Length	43.5	43	46.5
Loft	10.0	10.5	10.5
Weight	375	375	323
Shaft Weight	127	127	75
Swing weight	D1	D0	D3
Flex	251	268	272

Both the Persimmon and Steel had a Dynamic Gold S300 shaft and the PXG had an Accra Tour Z CB 75 M5 shaft 

 

 
The testing was done on an October day, about 12 degrees Celsius and no real wind. The golfer performed a warm-up before the testing. The ball used in the test was the Titleist ProV1. The methodology of the test was to hit 3 shots with the Persimmon, then 3 shots with the Steel, Titanium returning to the Persimmon and following the same procedure until 14 shots were hit with each. The shots were recorded on a Trackman 111 launch monitor.

Results

Driver	Club Speed MPH	Ball Speed MPH	Carry Yards	Total Distance Yards
Persimmon	96.1	141.0	207	235.6
Steel	97.4	142.1	214.4	241.3
Titanium	104.6	150.7	234.4	258
	Dispersion Feet	Launch Angle	Spin Rate	Height Feet
Persimmon	37.3	9.4	2810	59
Steel	32.2	10.8	2756	68
Titanium	36.2	9.9	2955	78

When it comes to driver performance, we are interested in two things, length and accuracy. As you'd expect the Titanium was the longest at 234.4 yards carry, 258 total, followed by the steel at 214.4, 241.3 and the shortest was the persimmon at 207 and 235.6. The temperature on the day of 12 degrees would be a factor in how far the balls went, we'd expect to see a little more distance in warmer temperatures.

 

For accuracy the steel was the best at an average of 32.2 feet from the target, with the titanium next at 36.2 and the persimmon at 37.3. Looking closer at the results photo none of the persimmon ended up on the target but a few each of the other two did.

 

Analysis

 

Why does the Titanium go further? Two factors give us length, one is ball speed and the other is the trajectory of the ball.

Let's deal with ball speed first. It comes from club head speed correctly applied. The titanium has significantly more club head speed then the other two, 104.6 compared to 97.4 and 96.1. There are three reasons behind this, club head weight, shaft weight and shaft length. The weight of the club head in the Titanium is 186 grams, the others are 200 grams. Lighter heads are swung faster. 

Next is shaft weight, the Titanium is 75 grams the others are 127 grams, again we will gain some speed from the lighter shaft. Thirdly, the length of shaft gives more speed, our testing suggests that each inch longer in the shaft gives 1 mph more speed. So the 46.5 inch Titanium length should give approx 3.5 mph club head speed then the 43 and 43.5 lengths in the others.

These are where the gains of 8.5 and 7.2 mph in club head speed are coming from.

 

Next is the trajectory, there again is a significant difference in the height of each of the three clubs, the titanium is the highest at a peak height of 78 feet, followed by the steel at 68 feet and a quite low 59 feet for the persimmon. The higher flight of the Titanium allows for a more optimal carry and more overall distance as a result. This is coming from the head design, a bigger head giving a lower centre of gravity, a higher launch and a higher flight as a result. Also more ball speed will give a higher flight too.

Accuracy wise, you'd have to say that the three are very close, the persimmon is 5.1 feet, the titanium 4 feet further away on average then the steel. Looking closer at this though the titanium is performing quite well in comparison, the shaft is longer, making it harder to control and the ball speed conversion is the worst of the three suggesting that the centredness of strike is also the worst. The ball speed to club head speed conversions of the three are, persimmon 1.47, steel 1.46 and titanium 1.44. 

The COR or coefficient of restitution in the titanium is higher then the other two which also should give better ball speed too. The weight of the other two heads though would help to give better ball speed conversions, momentum is mass combined with velocity, so with the heavier heads of steel and persimmon we should see better momentum being transferred to the ball. The COR gain of the titanium might cancel the loss of gain from the lighter head.

Driver	Attack Angle	Club Path	Face to Path
Persimmon	1.8	-1.0	1.4
Steel	0.7	0.7	-0.5
Titanium	-0.6	0.0	-1.7

Delving in a little deeper into the swing to see if the clubs make a difference to the swing, we can see that they do. First to notice is the attack angle, highest with the persimmon and lowest with the titanium. This is mainly to do with tee height relative to the size of the club head, the tee height we're used to for the current drivers is very high for the older drivers but encourage a more upward swing. Which is good for extra distance. The other notable thing from the swing impact factors is the fade pattern of the persimmon swing. I'd surmise this is because the golfer wanted to get the persimmon in the air more to get more distance and subconsciously went with a fade to get this.

 

Conclusion

 

The Titanium gives 22.4 more yards then the Persimmon and 16.7 yards more then the Steel, and no loss of accuracy. Both significant gains leading to jumps in performance and lower scores.

The bigger head design of the Titanium driver allows for more forgiveness. The more forgiveness allows for longer and lighter shafts to give more club head speed while maintaining accuracy. The weighting in the bigger head also allows for the a higher flight while keeping the spin down, giving maximum carry and over all distance. 

The next test will be to see if the older heads can be optimised more for distance, longer and lighter shafts will do this, but will this lead to less accuracy? Find out shortly.

Any comments and questions are welcome.