E55Kompressor vs C5 Z06
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CLS55 AMG
I used the dragtimes.com DA calculator and plugged in the ranger run from the list you posted. With a DA of -1500, 11.818 @ 117.26 comes out to 12.013 @ 115.255 at sea level, a difference of 2.0x mph.
The main thing that limits a high horsepower car's 60' is power, in this case not the lack of it, but rather the inability to apply all of it efficiently to the pavement. If it could apply the force with 100% efficiency, there's no doubt that it would win everywhere, but its efficiency is limited, in a perverse way, by lower weight. Now, if you overcome that efficiency gap with drag radials etc. and can make the available traction relatively equal, then it's a question of force/mass, but without sufficient traction a lot of that force is being wasted and the heavier car can indeed get a better 60' time, and beyond.
I do agree that the car w/the better power/weight ratio will definitely close the gap given time, but depending upon the difference in available traction it can take a lot longer than a moment. For example, if you look at the first Audi S4s to hit here, with 250 rated hp and 3800 or so pounds, those things have hit 1.8xx 60' times. Now, once past that they'll slow up and run hi 13's to low 14's, but they can scoot out there to a pretty good initial lead that takes more time than one would think to overcome (I know this from experience, used to own one
). That's a pretty vivid illustration of the extremes you can go to w/good traction.
It's correct that eventually the car with the superior hp/weight rato will catch up and pass, but the distance covered in a set amount of time is proportional to the sum of the energy expended over time, starting at time equals zero until whatever point at which we stop measiuring, here being 60'.
So if we compare the S4 to a higher hp rwd car running a 1.9 or whatever, even though it smokes him in weight/hp, the S4 could equal or beat its 60' time, due to the fact that even though the RWD car has scads more power, the AWD can transfer a much higher percentage of its total power to the ground without overpowering his available traction and turning his tires to mush, allowing very high rpm dropped clutch launches that would result in fishtailing and a huge cloud of smoke in the RWD torque monster.
So the AWD car has got this huge initial kick of power which is transmitted to the ground more efficiently by the AWD's huge traction advantage which would make the energy-vs-time curve look like a straight line jump up to some point, whereas the RWD car's would be more of a ramp due to having to modulate to avoid excessive spin.
Now once the RWD car overcomes this and gets up to maximum force, buh-bye, it's all over baby, but in those initial moments the AWD car will jump out until the RWD car's balance of accelerative vs. tractive force is optimized in its favor. You can see this effect very videly in the graphs of comparative acceleration of an Audi RS6 to an E55 in R&T's 0-100-0 shootout a few years back:
Even though the E55 gets to 100 1.2 sec faster and in a 152 ft shorter distance, the RS6's launch bite gets it ahead all the way out to just shy of 60 mph. They were able to launch it with a fairly high-rpm brake torque with the traction control off, but were forced to leave it on in the E55 and launch it from idle.
Of course, that's an extreme example. Wrt the SL55 vs the E55, the difference won't be nearly as huge as there's no AWD at play here, but there would be a difference...to quantify it we'd need to quantify the actual difference the wider tires and greater downward force on them gets it...the force is probably about 10% due to 10% higher weight, but I forget the equation...anyway, it should buy it something; if it can net it a tenth then I'd figure that cuts the E55's weight advantage essentially in half, so if that's the case I'd think if an E55 ran a 12.4 @ 116, the SL could probably run a 12.6-7 @ 112 to 114, depending upon its actual power (I suspect that since it's got a lower-restriction exhaust than the E, it is probably putting out more power, just not 30 more).
But to quantify this, we'd need some data. Unfortunately, it's sparse for the SL55, but the article I just cited for the RS6 vs E55 comparison also has an SL55 performing a run:
Their descriptions of the techniques that they used to make both runs do make it seem as though the SL55 had better traction: they were able to get the best times launching the SL55 without traction control on, while with the E55 they were forced to keep it on to avoid excessive spin, indicative of superior traction. Of course, our dear friends at R&T aren't kind enough to publish their 60' numbers; if they had another test somewhere that had 0-xx times available for both cars it'd help, as comparing 0-30 times between two cars is a good measure of their relative 0-60 times...but I can't find it.
I did find this, though: MT has tests of an E55 sedan, E55 wagon, and RS6:
_________RS6__E55_sedan__E55_wagon
0-30 mph___1.4___1.8___1.5
0-40 mph___2.2___2.4___2.2
0-50 mph___3.2___3.2___3.0
0-60 mph___4.3___4.2___4.1
0-70 mph___5.6___5.3___5.3
0-80 mph___7.1___6.5___6.5
0-90 mph___8.8___8.1___8.2
0-100 mph___10.7___9.7___10.0
1/4___mile___12.63 @ 108.64___12.39 @ 116.21__12.3 sec @ 113.8 mph
So you can see how that extra weight in the back helps the wagons (one reason why Nomads were popular way back when, in addition to drive-in theaters
): the wagon, with 420 pounds or so of extra weight, gives the AWD RS6 a good run to 30 mph, while both lay the smackdown on the E55 sedan, but as speeds rise the HP/weight advantage of the sedan closes the gap and it almost, but not quite, beats the wagon to the 1/4; even the sedan's almost-3 mph trap advantage couldn't overcome the traction advantage at launch.
It gets back to the efficiency thing: the 55k cars have more than enough power to run far better 60' times than they will normally hit in stock form, but they can't get the power down efficiently enough to do it. The RS6 can, which is why it hangs with them so well even though it's trapping 7-8 mph lower, and the E55 wagon's superior traction allowed it to slap the E55 sedan around a bit at low speeds, though it was clearly getting pulled at higher speeds due to the sedan's superior hp/weight. Imagine what kind of hole shot an AWD 55k car could get!!
The weight would affect the initial bite, but after that moment, the lighter weight plays into the advantage of the lighter car. Assuming everything else being equal. For instance, after say the initial 10ft, the lighter car is capable of of covering the remaining distance more quickly assuming there is no further loss of traction.
So the weight may help consistency, but there is a certain point when the lighter car should be able to cut a better 60ft. I would think this is the case with the stellar 60fts of the C5Zs on the list. Would you agree?
So the weight may help consistency, but there is a certain point when the lighter car should be able to cut a better 60ft. I would think this is the case with the stellar 60fts of the C5Zs on the list. Would you agree?
I do agree that the car w/the better power/weight ratio will definitely close the gap given time, but depending upon the difference in available traction it can take a lot longer than a moment. For example, if you look at the first Audi S4s to hit here, with 250 rated hp and 3800 or so pounds, those things have hit 1.8xx 60' times. Now, once past that they'll slow up and run hi 13's to low 14's, but they can scoot out there to a pretty good initial lead that takes more time than one would think to overcome (I know this from experience, used to own one
). That's a pretty vivid illustration of the extremes you can go to w/good traction.It's correct that eventually the car with the superior hp/weight rato will catch up and pass, but the distance covered in a set amount of time is proportional to the sum of the energy expended over time, starting at time equals zero until whatever point at which we stop measiuring, here being 60'.
So if we compare the S4 to a higher hp rwd car running a 1.9 or whatever, even though it smokes him in weight/hp, the S4 could equal or beat its 60' time, due to the fact that even though the RWD car has scads more power, the AWD can transfer a much higher percentage of its total power to the ground without overpowering his available traction and turning his tires to mush, allowing very high rpm dropped clutch launches that would result in fishtailing and a huge cloud of smoke in the RWD torque monster.
So the AWD car has got this huge initial kick of power which is transmitted to the ground more efficiently by the AWD's huge traction advantage which would make the energy-vs-time curve look like a straight line jump up to some point, whereas the RWD car's would be more of a ramp due to having to modulate to avoid excessive spin.
Now once the RWD car overcomes this and gets up to maximum force, buh-bye, it's all over baby, but in those initial moments the AWD car will jump out until the RWD car's balance of accelerative vs. tractive force is optimized in its favor. You can see this effect very videly in the graphs of comparative acceleration of an Audi RS6 to an E55 in R&T's 0-100-0 shootout a few years back:
Even though the E55 gets to 100 1.2 sec faster and in a 152 ft shorter distance, the RS6's launch bite gets it ahead all the way out to just shy of 60 mph. They were able to launch it with a fairly high-rpm brake torque with the traction control off, but were forced to leave it on in the E55 and launch it from idle.
Of course, that's an extreme example. Wrt the SL55 vs the E55, the difference won't be nearly as huge as there's no AWD at play here, but there would be a difference...to quantify it we'd need to quantify the actual difference the wider tires and greater downward force on them gets it...the force is probably about 10% due to 10% higher weight, but I forget the equation...anyway, it should buy it something; if it can net it a tenth then I'd figure that cuts the E55's weight advantage essentially in half, so if that's the case I'd think if an E55 ran a 12.4 @ 116, the SL could probably run a 12.6-7 @ 112 to 114, depending upon its actual power (I suspect that since it's got a lower-restriction exhaust than the E, it is probably putting out more power, just not 30 more).
But to quantify this, we'd need some data. Unfortunately, it's sparse for the SL55, but the article I just cited for the RS6 vs E55 comparison also has an SL55 performing a run:
Their descriptions of the techniques that they used to make both runs do make it seem as though the SL55 had better traction: they were able to get the best times launching the SL55 without traction control on, while with the E55 they were forced to keep it on to avoid excessive spin, indicative of superior traction. Of course, our dear friends at R&T aren't kind enough to publish their 60' numbers; if they had another test somewhere that had 0-xx times available for both cars it'd help, as comparing 0-30 times between two cars is a good measure of their relative 0-60 times...but I can't find it.
I did find this, though: MT has tests of an E55 sedan, E55 wagon, and RS6:
_________RS6__E55_sedan__E55_wagon
0-30 mph___1.4___1.8___1.5
0-40 mph___2.2___2.4___2.2
0-50 mph___3.2___3.2___3.0
0-60 mph___4.3___4.2___4.1
0-70 mph___5.6___5.3___5.3
0-80 mph___7.1___6.5___6.5
0-90 mph___8.8___8.1___8.2
0-100 mph___10.7___9.7___10.0
1/4___mile___12.63 @ 108.64___12.39 @ 116.21__12.3 sec @ 113.8 mph
So you can see how that extra weight in the back helps the wagons (one reason why Nomads were popular way back when, in addition to drive-in theaters
): the wagon, with 420 pounds or so of extra weight, gives the AWD RS6 a good run to 30 mph, while both lay the smackdown on the E55 sedan, but as speeds rise the HP/weight advantage of the sedan closes the gap and it almost, but not quite, beats the wagon to the 1/4; even the sedan's almost-3 mph trap advantage couldn't overcome the traction advantage at launch. It gets back to the efficiency thing: the 55k cars have more than enough power to run far better 60' times than they will normally hit in stock form, but they can't get the power down efficiently enough to do it. The RS6 can, which is why it hangs with them so well even though it's trapping 7-8 mph lower, and the E55 wagon's superior traction allowed it to slap the E55 sedan around a bit at low speeds, though it was clearly getting pulled at higher speeds due to the sedan's superior hp/weight. Imagine what kind of hole shot an AWD 55k car could get!!
Last edited by Improviz; Mar 14, 2010 at 12:55 PM.
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From: Cave Creek, AZ and Newport Beach
'22 G 63 AMG, '21 GLE 53 AMG, '20 NSX
FWIW,
My wife had an SL55 and I had an 04' E55 and we had more than 20 impromptu acceleration tests even changing drivers the E won every time.
BTW, the Hammer has 516 ft lbs of torque at 2600 rpm vs the Vett's 400 at a much higher RPM. I usually had the Vetts at the 1/8 mile but the stout ones would pull me at the top end if they had intake and exhaust.
To borrow an old hot rodder adage, torque is acceleration, hp is top speed.
If you run the torque to weight its easy to see why the E55 is pretty close to the Vett times.
My wife had an SL55 and I had an 04' E55 and we had more than 20 impromptu acceleration tests even changing drivers the E won every time.
BTW, the Hammer has 516 ft lbs of torque at 2600 rpm vs the Vett's 400 at a much higher RPM. I usually had the Vetts at the 1/8 mile but the stout ones would pull me at the top end if they had intake and exhaust.
To borrow an old hot rodder adage, torque is acceleration, hp is top speed.
If you run the torque to weight its easy to see why the E55 is pretty close to the Vett times.
