Quote:
Originally Posted by epaulo
sorry numbers just dont seem right, only way the gtr can compete is if its pushing out well more then 500hp and tq given its weight disadvantage.
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ice don't make enough torque to get a car moving with 1:1 gearing. gearing multiplies power. the gtr uses more gear multiplication, so that it in fact has a better power/weight ratio than either the porsche or z06. if this analysis doesn't make sense to you, just take an automotive engineer's word at face value.
here are the final drive ratios:
......gtr...z06...911
1st 15.02 9.10 13.14
2nd 8.51 6.09 7.36
3rd 5.88 4.45 5.09
4th 4.63 3.42 4.06
here's available hp in each gear:
......gtr...z06...911
1st 7210 4596 6307
2nd 4085 3075 3533
3rd 2822 2247 2443
4th 2222 1727 1949
the test weight of the gtr, z06 and 911 are 3960 lb, 3350 lb, and 3710 lb, respectively. power to weight ratio in 1st gear is 1.82 hp/lb, 1.37 hp/lb, and 1.7 hp/lb. power/weight in 3rd gear is 0.71 hp/lb, 0.67 hp/lb, and 0.66 hp/lb. the gtr, despite having slightly lower peak hp, has more hp at the wheels in first gear, and this is why it accelerates faster than mere figures would show. i hope this helps.
fwiw, an ls3 c6 z51 with 3.70:1 dif will come very close to the z06 in 0-60. 3.70 over stock 3.42 gearing gives 8.2% more power (not engine power, power at the wheels!) since the ls3 puts down 394 whp, this would give 426 whp, or a 30 whp gain.