Basic questions about swing speed, clubhead weight and distance

[Chipless]

Wondering if someone could help me to understand the basics of how swing speed and clubhead weight work together to determine the distance a ball will travel.

Pretend a swing with a certain club makes perfect ball contact and the ball travels a specific distance.  What if you add 10% to the weight of the clubhead without changing the swing speed or anything else?  How much farther would the ball travel?  And what if the clubhead was 10% lighter?

I ask these questions realizing that a heavier club will naturally be swung slower.  But I'm still curious about how these factors inter-relate.  For example, if 10% more clubhead weight means a decrease of 5% speed, but still gives you 5% more distance, then it would be a tradeoff that seems to be worth considering.

On that note, I think I have a basic understanding about how players get fit for clubs.  But I haven't seen anyone reference the ideal clubhead weight for a particular swing speed.  Is this a non-issue, because the benefits would be too small to matter?

Same questions for clubhead speed.  Say the swing speed increases or decreases by 10%.  How much distance would we gain or lose?

[mvmac]

Tough question.  Also depends on where you put or take the weight off.  Sorry it's complicated.  Distance is a product of many things, hitting it solid, launch angle, spin rate, angle of attack.  But to answer your question, in a general sense, I think something like 2 mph more swing speed can be about 5 yards.  Here are some number off Trackman

Ideal Numbers:

Ball Speed	Launch Angle	Back Spin (rpm's)	Carry Distance
170 mph	11.5-15.5+*	2000-2400	289 yards
160 mph	12-16+*	2200-2650	271 yards
150 mph	13-16.5+*	2300-2800	252 yards
140 mph	14-17+*	2350-2950	233 yards
130 mph	14.5-17*	2400-3100	215 yards
120 mph	15-17*	2500-3300	196 yards

[saevel25]

Since the equations governing the transfer of energy is 1/2 mass times velocity squared. So as you can see velocity has the most effect on the transfer of energy from the golf club to the golf ball.

Lets say you swing a 300 gram clubhead at 100 mph, In an ideal world with 100% transfer of energy,

If you increase the mph by 10, your going to increase the energy transfered by about 21%

If you increase the clubhead weight by 20 grams, your going to increase the energy transfered by about 6.7%

If 5 yards per 2 mph increase, that means there was about a 4-5% increase in energy possible.

To get that same % increase you would have to increase your clubhead weight from 300 grams to 312 grams, and not loose any clubhead speed.

Given most clubheads are getting lighter and lighter, like the ping G20 is 204 grams clubhead. That would mean, about 8 grams increase in clubhead weight.

[Stretch]

From what I've read, you can ballpark ball speed relative to clubhead conditions thusly:

V ball =  V clubhead

1 + e 1 + m/M

cos(loft) * (1 - 0.14*miss)

m = ball mass, M = clubhead mass, e = coefficient of restitution, cosine of the club's loft angle to roughly account for energy lost to glancing blow, miss = amount in inches by which impact is away from the sweet spot.

Realize this does little to answer your question about how club weight affects clubhead speed. Only thing I know in that regard is that it is the weight of the shaft -- rather than the head -- that is the major determinant. This is why we see the current trend to ultralight driver shafts for lower-swing-speed golfers. In theory, these let you both maintain clubhead mass and increase swing speed (by lowering the total weight of the club) -- which according to our formula should yield higher ball speeds. Does it actually work? I don't know.