Quote:
Originally Posted by jparnes1
Teague, your'e saying the lower the hp/weight and tq/weight ratios in the comparo chart you posted are better? Maybe I'm missing something, but increasing the weight or decreasing hp or tq makes for a lower number. How is that better?
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There may be other methods, but the method I learned years ago is dividing the vehicle weight by the horsepower or torque.
(Edit Note: I believe this methods is better known as the pound per horsepower ratio. The true PTW ratio method is dividing horsepower or torque by the vehicle weight, which would result in a higher number.)
So as you can see from the chart the 911 Turbo S has significantly better (numerically lower) PTW and TTW ratios than its sibling Boxster S w/ MT. So even though the Boxster S beats the pants off the 911 Turbo S in the weight department, the Turbo S' overwhelming horsepower and torque results in lower ratios. On the other hand, we all know the mid-engine Boxster S is universally praised for its balance and handling. So huge horsepower and torque figures are not the ultimate goals. A great chassis, light weight, tire/wheel combo, correct spring, damper and anti-roll components all come into play.
On the other hand, the Boxster S may have a slight TTW advantage vs the Z4 35i, but the Boxster S' naturally aspirated engine doesn't built that torque until much higher up in its RPM range so the win goes to the BMW with its TT engine. The 35is further improves that comparison, but when you add the tuner factor it's not really a fair comparison anymore. Refine a few of the Z4's suspension bits and I'd be curious to see if BMW could come up with something better in a Z4 model.
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