Technical Tips
February 2009
Technical Terminology Used by the Golf Industry That You Should Know.
When shopping for a golf club there may be numbers on the head or shaft that mean some sort of measurement. Maybe these numbers could help you select a club that is better suited for your needs as a golfer. Measurements from a fitting can be used to select Drivers that would reward your swing. The following measurements apply to current Drivers, most Fairway Woods and some Hybrids.
What is C.O.R.?
Coefficient of Restitution, or C.O.R., is one of the most important terms in golf. This is a measurement calculated by the U.S.G.A. when it tests golf clubs for conformity. If a golf club does not meet the C.O.R. standards, the U.S.G.A. could rule it nonconforming and illegal for tournament play.
The maximum C.O.R. allowed by the U.S.G.A. is .830. This transfer of energy is a measurement of how much energy is transferred from the club head to the ball upon impact. The U.S.G.A. only allows 83% of the club head energy to be transferred to the ball.
What is C.T.?
Characteristic Time, or C.T., is a measurement taken by the U.S.G.A. when testing golf clubs. This measurement determined how long the ball lingers on the face of the club upon impact. The longer the ball stays on the face of the club, the farther the ball will travel.
Trampoline Effect
When a golfer strikes a golf ball, the goal is to compress the face of the club. The problem most golfers experience, and they don't know this, is, most golfers can not compress the face of the club because golf clubs are built to be tested at 110 MPH, per U.S.G.A. protocol. If a golfer does not swing his driver at 110 MPH, he can not compress the face of the club and does not experience the Trampoline Effect.
Smash Factor
The maximum Smash Factor allowed by the U.S.G.A. is 1.50. This measurement is the difference between swing speed and ball speed.
If your swing speed is 100 MPH, and your ball speed is 150 MPH, your Smash Factor is 1.50.
If your swing speed is 110 MPH and your ball speed is 163 MPH, your Smash Factor is 1.48.
If your swing speed is 95 MPH and your ball speed is 125 MPH, your Smash Factor is 1.31.
To calculate, divide your ball speed by swing speed (150/100=1.50).
