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      10-28-2008, 01:05 AM   #67
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Quote:
Originally Posted by bruce.augenstein@comcast. View Post
"Pancho! My horse!"

"More misadventures, my lord?"

"And adventures, too..."
Really Bruce say something useful and concrete or shut your trap. Your schtick is so tiring and polluting.
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      10-28-2008, 01:13 AM   #68
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Originally Posted by Steved View Post
And that's precisely our plan. I won't say much more, since plans have a habit of backfiring, especially the weather conditions at Nurburg this time of year, but we'll see if we can re-create this lap using a standard GT-R and standard GT2, then see what we discover.
Good to hear Steve. Sounds like the makings of another great article. However, one issue that will likely arise about any such "apples to apples" testing is "which car" in what state of tune was tested. Based on the large spread of GT-R results (tracks, strip, street drags, etc.) this is particularly concerning. As much as dynos are not perfect, might I still suggest some very careful dynos and 1/4 mi and perhaps other straight line acceleration tests of the vehicles involved? These will offer further evidence of the true power of each vehicle.

Cheers.
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      10-28-2008, 03:11 AM   #69
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Originally Posted by swamp2 View Post
Good to hear Steve. Sounds like the makings of another great article. However, one issue that will likely arise about any such "apples to apples" testing is "which car" in what state of tune was tested. Based on the large spread of GT-R results (tracks, strip, street drags, etc.) this is particularly concerning. As much as dynos are not perfect, might I still suggest some very careful dynos and 1/4 mi and perhaps other straight line acceleration tests of the vehicles involved? These will offer further evidence of the true power of each vehicle.

Cheers.
If the cars a supplied by a dealer or press cars then this will be stated in the article. I think you are mocking their intelligence here swamp. By the way, dyno results can be misleading, 1/4mile times are a better gauge of output. Plus they will post telemetry throughout the course so you will have load of data the scribble about in the future.
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      10-28-2008, 09:07 AM   #70
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Quote:
Originally Posted by swamp2 View Post
Really Bruce say something useful and concrete or shut your trap. Your schtick is so tiring and polluting.
You thought being compared to Don Quixote was tiring, polluting, and somehow a putdown?

Huh. I guess we're all ignorant in different areas.

Shut my trap? Wow! Swamp the Sanctimonious turns nasty!

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      10-28-2008, 10:17 AM   #71
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Originally Posted by bruce.augenstein@comcast. View Post
Shut my trap? Wow! Swamp the Sanctimonious turns nasty!
I must admit, that statment of swamp's was 'pot calling kettle black'. Maybe memory span makes him forget how he is to others or it's a split personality at work.
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      10-28-2008, 03:24 PM   #72
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Bruce, perhaps I misunderstood the reference, my apologies if so.

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Originally Posted by footie View Post
I must admit, that statment of swamp's was 'pot calling kettle black'. Maybe memory span makes him forget how he is to others or it's a split personality at work.
Regardless of a compliment or not asking to keep relevant on on topic (even if harshly) isn't as bad as your ad hominem name calling.
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      10-28-2008, 04:03 PM   #73
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Quote:
Originally Posted by swamp2 View Post
Bruce, perhaps I misunderstood the reference, my apologies if so.[/quote0

Well that's a first, finally getting a conscience.

Regardless of a compliment or not asking to keep relevant on on topic (even if harshly) isn't as bad as your ad hominem name calling.
Well you see, when you are continually ignorant to someone over and over again it gets to a point when enough is enough, that point was a short while ago but calm has returned.
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      10-28-2008, 05:48 PM   #74
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Originally Posted by footie View Post
Well you see, when you are continually ignorant to someone over and over again it gets to a point when enough is enough, that point was a short while ago but calm has returned.... Well that's a first, finally getting a conscience/
Herein I have always graciously admitted errors, typos, mistakes, etc. each and every time I've made them. I've even done so simply from being too harsh on folks. You can't point out cases to the contrary. As well I offer apologies quickly and without stipulations when I owe them.
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      10-28-2008, 08:31 PM   #75
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Hey fellas, everyone is over at the ZR1 thread, this is old now.

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      10-29-2008, 08:55 PM   #76
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OK, I finally found the time to read through all this. Great discussion IMO! Thanks for taking the time to post this Swamp.

Swamp has done a great job in presenting a case for his estimate, and Footie has done an equally solid job critiquing it. (I think Swamp should give Footie more credit considering Footie does not have a technical background despite the fact that Footie does seem to wonder off topic at times.)

A few questions/observations for Swamp:

1. Where is the spreadsheet??? I wanted to see the numbers, but can't find the file anywhere on this thread. Am I just overlooking it somewhere?

2. Wind is modeled as static force, which is probably not the case. I am not an expert on weather dynamics, but I bet surface winds change direction often, and there is the possibility of short gusts, and even direction reversals depending on topography, etc.

3. You are agreeing that a static 15mph tail wind would validate the observed performance of a 530hp GTR, and saying there is no reason to believe that is the case since Nissan would not have ran the test under windy conditions. I don't think that is sufficient rationale. It might be possible that the track layout and the geography, in conjunction with a specific wind direction on a specific day, might actually result in positive net tailwind on the faster straights on a windy day. In order words, roughly speaking, one might trade off headwind on slower parts of the course for tailwind on the faster parts.

4. You are using a WOT assumption for all cars throughout the section you observed. I don't drive on tracks at those speeds, but when you are on such long straight at such high speeds, there might be reason/hesitation not to go absolutely WOT all the time. Since I can't see the spreadsheet, I can't comment on this in more detail.

5. As Bruce mentioned, atmospheric conditions on the different days might lead to output differences.

6. Does your CarTest speed vs. time output match the speed vs. time data on the ZR1 run precisely over time during the duration? Again, I can't see the data for myself. You have only reported time to complete the track section on this thread.
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      10-29-2008, 11:16 PM   #77
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Quote:
Originally Posted by lucid View Post
OK, I finally found the time to read through all this. Great discussion IMO! Thanks for taking the time to post this Swamp.

Swamp has done a great job in presenting a case for his estimate, and Footie has done an equally solid job critiquing it. (I think Swamp should give Footie more credit considering Footie does not have a technical background despite the fact that Footie does seem to wonder off topic at times.)
Thanks for having a look, I very much agree with you basic point of questioning assumptions rather than attacking the messenger and the method.

Quote:
Originally Posted by lucid View Post
A few questions/observations for Swamp:

1. Where is the spreadsheet??? I wanted to see the numbers, but can't find the file anywhere on this thread. Am I just overlooking it somewhere?
I am certain I attached it to the original post. But is also seems very unlikley it disappeared. The real irony would be all of the criticism if no one replying even bothered to look at the results. That is awfully telling. I have attached both spreadsheets in a zip file in this post.

Quote:
Originally Posted by lucid View Post
2. Wind is modeled as static force, which is probably not the case. I am not an expert on weather dynamics, but I bet surface winds change direction often, and there is the possibility of short gusts, and even direction reversals depending on topography, etc.
Wind is modeled with F = 1/2 pxCdxAxv^2 in CarTest, just like the drag force. Surely wind varies in style with some being steady and others more gusty. You can with enough simulation capability model gusty wind but who would ever have a measurement of that and how accurate would it be? As well I would argue that capturing an average wind speed would capture a majority of the relevant effect over a long distance, which was the case in the straight section I looked at.

Quote:
Originally Posted by lucid View Post
3. You are agreeing that a static 15mph tail wind would validate the observed performance of a 530hp GTR, and saying there is no reason to believe that is the case since Nissan would not have ran the test under windy conditions. I don't think that is sufficient rationale. It might be possible that the track layout and the geography, in conjunction with a specific wind direction on a specific day, might actually result in positive net tailwind on the faster straights on a windy day. In order words, roughly speaking, one might trade off headwind on slower parts of the course for tailwind on the faster parts.
Yes, that is correct and is what I stated. Anything is possible but is it likely? I just don't think so. Wind most often has a fairly well defined direction. If wind helped the GT-R in this straight it would hurt it in other faster/fairly straight sections as well as hurt it on about half the corners.

Quote:
Originally Posted by lucid View Post
4. You are using a WOT assumption for all cars throughout the section you observed. I don't drive on tracks at those speeds, but when you are on such long straight at such high speeds, there might be reason/hesitation not to go absolutely WOT all the time. Since I can't see the spreadsheet, I can't comment on this in more detail.
Yes WOT is an assumption. The section is quite straight, the cars accelerate hard to about 175 and there is absolutely no reason to believe there was any other throttle condition other than WOT. This must be one of the most solid "assumptions" in the analysis.

Quote:
Originally Posted by lucid View Post
5. As Bruce mentioned, atmospheric conditions on the different days might lead to output differences.
This is not only a possbility but is a factor affecting the simulations. However, as we know these effects are much less for a turbo charged engine and are not really enormous effects. I would call them "second order" behind power to weight for sure. Lastly, this information is probably not obtainable as I pointed out to Bruce. If it is known it can be added to the simulation parts of the analysis.

Quote:
Originally Posted by lucid View Post
6. Does your CarTest speed vs. time output match the speed vs. time data on the ZR1 run precisely over time during the duration? Again, I can't see the data for myself. You have only reported time to complete the track section on this thread.
Yes, each car simulated matches the available data. Specifically in the time result the ZR1 matches within 2-4%, ACR, within 1-6% and of course with no data available for the GT-R. Also, in addition to these absolute percentages some deviations are + and others -, showing no specific systematic error. I thought that was particularly strong in terms of matching prediction with test.

One additional point is worth bringing up. Whenever possible I chose very conservative values/assumptions which favor a LOW estimate of the under rating. Such examples include very conservative transmission losses (equivalent to the other two RWD vehicles) and very quick transmission shift times for the GT-R. It is clear evidence of a distinct pro GT-R/anti under rating point of view when ONLY assumptions which provide a larger under rating are questioned in all of the replies. Like many other situations with a tremendous number of contributing variables you have to focus first on the most dominant factors and count on some of the other minor unknowns affecting results in one direction and others pushing in the opposite direction. No this can't be "proved" but it is most likely.

I am looking forward to your thoughts on the additional regression work as well. It is fairly clear/strong evidence to me that those particular cars were not as under rated as the 7:29 car.
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      10-30-2008, 02:51 AM   #78
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swamp,

Look back to the original posts and I don't see an attack on you or your methods, only that I felt you were wrong and gave a very valid reason.

Quote:
OK swamp,

I thought I would look through YOUTUBE for the videos and found one which matched up the ZR1 with GTR, both coming on to the final straight at the same time.

Well to cut a long story short, when the bridge when out of view in the ZR1 the Nissan's time log read 7:06.38 and when the bridge when out of view in the GTR it was 7:08.99, over 1.5s later. Now I don't have either the equipment or the time to work this out so maybe you might be able to estimate the speed of the GTR at that point.

I'm guessing it's a good 10mph slower than the ZR1 which was doing 176mph at that time. If my estimates are right and lets say they both rounded the corner at the same speed (which I doubt) that means the Vette is pulling harder.

P.S.
I still believe that the time is constant with which another GTR could do and that all of them are under-rated by about 10%.
Your problem with me is that I continue to disagree with you on things and that is based on logical/real life experience other than simulations. I gave a very valid reason why the Vette at that time didn't max out, wind can cause the car to wander, I know I have experienced it at these speeds. I also gave a valid reason for looking else where on the track as the trees and geographical position might mean wind is less of an issue and in that comparison the Vette was comfortably quicker.

Is it a case that when someone else points out possible errors in your methods it OK and you listen but when it's me, because of my continued hole picking you've build up a wall to reason.
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      10-30-2008, 11:52 AM   #79
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Quote:
Originally Posted by swamp2 View Post
I am certain I attached it to the original post. But is also seems very unlikley it disappeared. The real irony would be all of the criticism if no one replying even bothered to look at the results. That is awfully telling. I have attached both spreadsheets in a zip file in this post.
I rechecked your initial post and cannot see an attachment. Your recent attachement is there, but my PC is saying it is corrupted. Can you open it yourself? It is interesting that people will criticise harshly without trying to understand what has been done.

Quote:
Originally Posted by swamp2 View Post
Wind is modeled with F = 1/2 pxCdxAxv^2 in CarTest, just like the drag force. Surely wind varies in style with some being steady and others more gusty. You can with enough simulation capability model gusty wind but who would ever have a measurement of that and how accurate would it be? As well I would argue that capturing an average wind speed would capture a majority of the relevant effect over a long distance, which was the case in the straight section I looked at.
I understand how CarTest would model wind effects as drag. I meant to say wind effects are dynamic, and depending on the day and topography, can change significantly at the surface (I think neither of us are experts on how much wind forces can vary, so I am not going to debate that. Just bringing it up). I wouldn't expect you to be able to model that. But the point is that if such variability can affect performance, your analysis does not account for it, which might be a factor in the outcome, that's all. Your analysis shows that a delta of 15mph can drastically alter the outcome, so it is not so far-fetched. How likely or unlikely, I don't know.

Quote:
Originally Posted by swamp2 View Post
Yes, that is correct and is what I stated. Anything is possible but is it likely? I just don't think so. Wind most often has a fairly well defined direction. If wind helped the GT-R in this straight it would hurt it in other faster/fairly straight sections as well as hurt it on about half the corners.
Keep in mind this is a very long track covering diverse topography. I bet there are all sorts of wierd flow effects when wind blows around distinct landscape features. Sometimes the road follows the exposed crest of a hill, and other times, it moves along a deep and very well sheltered valley. I think you are oversimplying how differently wind can affect the performance at different points on the track. If there are such differences, Nissan might have indeed preferred to go out on a relatively windy day if the wind was blowing in a particular way. Again, I am not an expert on that, so I can't comment how likely or unlikley, but the possibility is there.

Quote:
Originally Posted by swamp2 View Post
Yes WOT is an assumption. The section is quite straight, the cars accelerate hard to about 175 and there is absolutely no reason to believe there was any other throttle condition other than WOT. This must be one of the most solid "assumptions" in the analysis.
I just watched the tapes of that section. They do seem to be going all out indeed. One thing is that this is a public track with all sorts of strange things happening on it. If I were driving at 150+ mph, I'd be pretty concerned with what might be happening ahead of me and scanning the horizon. If you even remotely think that you might see something up ahead that's not right, the tendency would be to lift slightly. But I guess these particular runs might have been on a closed track. I think the previous run wasn't though as I vaguely remember the GTR passing another car during that one. At any rate, there might be other reasons why you might feel unsafe with a street car on a track like this one, which might cause you to hesitate. That's why I would like to see the data you extracted.


Quote:
Originally Posted by swamp2 View Post
This is not only a possbility but is a factor affecting the simulations. However, as we know these effects are much less for a turbo charged engine and are not really enormous effects. I would call them "second order" behind power to weight for sure. Lastly, this information is probably not obtainable as I pointed out to Bruce. If it is known it can be added to the simulation parts of the analysis.
Well, given we don't have the weather information, you can do a sensitivity analysis by trying some scenarios to see if it makes a major difference.

Quote:
Originally Posted by swamp2 View Post
Yes, each car simulated matches the available data. Specifically in the time result the ZR1 matches within 2-4%, ACR, within 1-6% and of course with no data available for the GT-R. Also, in addition to these absolute percentages some deviations are + and others -, showing no specific systematic error. I thought that was particularly strong in terms of matching prediction with test.
Just to be clear, I am referring to extracing several (time, speed) datapoints along the course from the ZR1 clip and comparing them with the simulation output. Since you only have data on this for the ZR1, that's the only possible comparison you can do of this nature. If those datapoints throughout the section don't match, then you have an incaccurate simulation tool even if the final datapoints at the end of section match. If the datapoints throughout the section match, then I'd say you've a got a solid simulation.

Quote:
Originally Posted by swamp2 View Post
One additional point is worth bringing up. Whenever possible I chose very conservative values/assumptions which favor a LOW estimate of the under rating.
I understand that you are doing this, which is the right thing to do.

Quote:
Originally Posted by swamp2 View Post
I am looking forward to your thoughts on the additional regression work as well. It is fairly clear/strong evidence to me that those particular cars were not as under rated as the 7:29 car.
Yes, what you mentioned about the deviation decreasing as the track gets "tighter" is interesting. You are attributing that to the actual power/weight of the GTR, but if the "GTR can put down power earlier" argument has merit, that can also contribute to decreasing deviation since the car will carry whatever speed it can build earlier along the straight even if it does not necessarily accelerate any faster on the straight itself, so there might be a combination of those two issues.
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      10-30-2008, 01:32 PM   #80
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Quote:
Originally Posted by footie View Post
I gave a very valid reason why the Vette at that time didn't max out, wind can cause the car to wander, I know I have experienced it at these speeds. I also gave a valid reason for looking else where on the track as the trees and geographical position might mean wind is less of an issue and in that comparison the Vette was comfortably quicker.
I am so unbelieveably sick and tired of repeating myself. How many times does it take? This is not about why the ZR1 did not achieve a higher top speed on the section I did the analysis. This is strictly about acceleration when under WOT on one of the fastest straight sections on the track. Please show us your "analysis" over multiple points, in a straight section, with good reason to believe in full WOT conditions where the ZR1 significantly bests the GT-R. PLEASE show us.

Last edited by swamp2; 10-30-2008 at 01:54 PM.
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      10-30-2008, 01:54 PM   #81
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Quote:
Originally Posted by lucid View Post
I rechecked your initial post and cannot see an attachment. Your recent attachement is there, but my PC is saying it is corrupted. Can you open it yourself? It is interesting that people will criticise harshly without trying to understand what has been done.

...
I can open the attachment and files contained above. I also emailed them to you. Funny indeed! Typical premature knee jerk reaction. Although to be fair the post itself did describe fairly well what I did.

All pretty reasonable criticisms^, but also the only thing left to do would indeed be a ton of bounding/sensitivity studies. Would be interesting but the tail wind example was probably the most important one. Again many small effects which can vary in terms of benefit/detriment and they will tend to average out. As well I think all such studies would do at this point would be to increase the confusion and take things even further off topic.

The methodology for getting the differences between the ACR times and predictions was to assume a faster corner exit speed for the ACR (totally justified IMO) and to then match the ZR1s acceleration. Not rigorous nor particularly strong assumption but it does make everything loosely consistent. Really we can leave the ACR out as a weaker part of the argument. There was no speed data so is is much harder to compare. The primary argument here is ZR1 vs. GT-R.
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      10-30-2008, 02:30 PM   #82
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Quote:
Originally Posted by swamp2 View Post
I can open the attachment and files contained above. I also emailed them to you. Funny indeed! Typical premature knee jerk reaction. Although to be fair the post itself did describe fairly well what I did.

All pretty reasonable criticisms^, but also the only thing left to do would indeed be a ton of bounding/sensitivity studies. Would be interesting but the tail wind example was probably the most important one. Again many small effects which can vary in terms of benefit/detriment and they will tend to average out. As well I think all such studies would do at this point would be to increase the confusion and take things even further off topic.

The methodology for getting the differences between the ACR times and predictions was to assume a faster corner exit speed for the ACR (totally justified IMO) and to then match the ZR1s acceleration. Not rigorous nor particularly strong assumption but it does make everything loosely consistent. Really we can leave the ACR out as a weaker part of the argument. There was no speed data so is is much harder to compare. The primary argument here is ZR1 vs. GT-R.
You'll get me to buy in to your conclusion to a great extent if the (speed, time) datapoints match.

When did you send me email? I didn't get it. My email has been acting up recently. The attachment doesn't work for me, but maybe the it's the unpacking software. I'll try another one.
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      10-30-2008, 02:39 PM   #83
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Quote:
Originally Posted by swamp2 View Post
I am so unbelieveably sick and tired of repeating myself. How many times does it take? This is not about why the ZR1 did not achieve a higher top speed on the section I did the analysis..
But please explain why the ZR1 wouldn't keep the pedal firmly planted to achieve the maximum speed along this very straight piece of track and thus improve it's time even further. The last time I raced it was the only way of winning, maybe things have changed since then and it's all done by simulations to see who's the winner and no one actual takes to the track at all.

Quote:
Originally Posted by swamp2 View Post
This is strictly about acceleration when under WOT on one of the fastest straight sections on the track. Please show us your "analysis" over multiple points, in a stright section, with good reason to believe in full WOT conditions where the ZR1 significantly bests the GT-R. PLEASE show us.
There are some pointers along the straight that you can use to gauge how far apart these two cars will be when each pass these points.

1/ Audi Banner over head early on the straight.

ZR1 reaches it 0.3s ahead of the GTR at a speed of 144mph. At that point using my eyes as a gauge the ZR1 would be about 3 lengths ahead of the GTR.

2/ Taller sign at the right hand side (second in the line)

ZR1 reaches this 0.6s ahead of the GTR at a speed of 163mph. Again using my eyes as a gauge on this the ZR1 looks to be about 8~9 car lengths ahead of the GTR.

3/ The Bridge just before the kink.

ZR1 reaches this 0.9s ahead of the GTR at a speed of 176mph. At this speed it's harder to gauge but I reckon it looks close to 12 car lengths ahead.

Doing the maths (60mph = 1 mile per minute) and there is 1609m in a mile.

At point 1 the ZR1 was 19.3m ahead of the GTR
At point 2 the ZR1 was 46.9m ahead of the GTR
At point 3 the ZR1 was 76.1m ahead of the GTR.

So within the time it took the ZR1 to accelerate from about 100mph to 144mph it had pulled out about 4 car lengths on the GTR. By the time it had increased this by 19mph it was almost 10 car lengths ahead and finally by the bridge it was almost 16 car lengths ahead.

Now go back to your simulation and figure in these gaps based on these speed points and see if you come back with a GTR with 550hp.
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      10-30-2008, 02:43 PM   #84
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Originally Posted by swamp2 View Post
The methodology for getting the differences between the ACR times and predictions was to assume a faster corner exit speed for the ACR (totally justified IMO) and to then match the ZR1s acceleration. Not rigorous nor particularly strong assumption but it does make everything loosely consistent. Really we can leave the ACR out as a weaker part of the argument. There was no speed data so is is much harder to compare. The primary argument here is ZR1 vs. GT-R.

Use good old time pointers to see how much faster or slower the ACR is than the ZR1 or GTR. I remember doing it a while ago and the Viper was in between the Vette and the Nissan, though it was riding the limiter for most of the time and would have been clearly quicker than both if this hadn't been the case.
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      10-30-2008, 05:56 PM   #85
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Quote:
Originally Posted by footie View Post
But please explain why the ZR1 wouldn't keep the pedal firmly planted to achieve the maximum speed along this very straight piece of track and thus improve it's time even further. The last time I raced it was the only way of winning, maybe things have changed since then and it's all done by simulations to see who's the winner and no one actual takes to the track at all.
I have said about a million times I do not know why the ZR1 maxed out at around 176. But before that is it quite evident that all cars were WOT and that is what matters.

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Originally Posted by footie View Post
There are some pointers along the straight that you can use to gauge how far apart these two cars will be when each pass these points.

1/ Audi Banner over head early on the straight.

ZR1 reaches it 0.3s ahead of the GTR at a speed of 144mph. At that point using my eyes as a gauge the ZR1 would be about 3 lengths ahead of the GTR.
You need to look as absolute times in each video from tha car clocks and then subtract the time of the corner entry point. Based on this I totally disagree. I say the delta t from corner exit to Audi banner were ZR1 = 5.9s, GT-R 6.7s, difference is a full 0.8 seconds and this is partly why I believe the ZR1 exited faster!

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Originally Posted by footie View Post
2/ Taller sign at the right hand side (second in the line)

ZR1 reaches this 0.6s ahead of the GTR at a speed of 163mph. Again using my eyes as a gauge on this the ZR1 looks to be about 8~9 car lengths ahead of the GTR.
At 164 mph for the ZR1 I call the time difference to the same point on the track 1.1 seconds, ZR1 ahead. No idea where you are getting these crazy figures from.

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Originally Posted by footie View Post
3/ The Bridge just before the kink.

ZR1 reaches this 0.9s ahead of the GTR at a speed of 176mph. At this speed it's harder to gauge but I reckon it looks close to 12 car lengths ahead.

...

Now go back to your simulation and figure in these gaps based on these speed points and see if you come back with a GTR with 550hp.
Again including the bridge, well after the ZR1 stopped accelerating, is not relevant. I am using only the times when all cars are WOT. The bridge is long, long after that point. I have repeated this about 10 times up to now, why won't this sink in?

I am not saying the GT-R is faster in this straight section, the ZR1 is ahead from 0.4 - 1.1 seconds at identical points along the track (and just FYI I used many many more points than you consider here above). The ZR1 is always ahead! Please see my spreadsheet. It seem abundantly clear you still have not looked at it and that you can not read the videos properly.

When a car is accelerating you can not estimate distances in the lead based on speeds at single data points. This is physics 101. Talk about ridiculously incorrect analysis. This takes simulation or calculus to determine! Sharpen up your pencil, have another think about it.

So even though the ZR1 was faster and most likely exited faster what I am saying is that the observed (lesser) performance of the GT-R is still consistent with 550 hp.

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      10-30-2008, 06:41 PM   #86
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swamp,

Like Lucid, I tried to open the file but no go. Don't know for why.

I believe my observations of the times are roughly correct, as I chose to use the Nissan's timer as it was in hundredth unlike the Vette timer. I also believe my observations of the distance the Vette was gaining to be correct, based on experience and good judgement.

Motortrend tested the ZR1, GTR, 599 and GT2

And the times for the 1/4mile runs showed the ZR1 to be 0.1s ahead of the 599, 0.2s ahead of the GT2 and 0.4s ahead of the GTR. Now if you were to look at the acceleration times by speed the ZR1 totally destroys the GTR, posting a time 1.1s ahead of the GTR to 100mph, but only 0.4s ahead by the 1/4mile. Call me stubborn but these figures don't sound unlike what is seen happening in the comparison video on the ring. I know we are talking about higher speeds but I think everyone else knows the point I am trying to make. Edmunds also tested both the ZR1 and GTR and posted dyno results, with the ZR1 (505hpwhp) and the GTR (406whp), is it possible that the GTR has a 24% drivetrain lose, personally I doubt it. I even doubt 20%.

As I can't open the file, can to provide some split times with speed and distance points for both cars so as I can get a feel for your data and see how it looks.

P.S.
I still disagree with the ZR1 exiting the corner quicker, based on watching the entire two videos and matching the two cars from corner to corner, if anything the GTR should be the one leaving that corner the sooner.
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      10-30-2008, 08:43 PM   #87
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Interesting analysis being performed by you guys. Bravo!
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      10-30-2008, 09:21 PM   #88
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Quote:
Originally Posted by lucid View Post
You'll get me to buy in to your conclusion to a great extent if the (speed, time) datapoints match.

When did you send me email? I didn't get it. My email has been acting up recently. The attachment doesn't work for me, but maybe the it's the unpacking software. I'll try another one.
I sent it to your personal email, not through PM on the forum.

I tried again with both my Mac and Windows machines and the zip file opens perfectly to reveal two spreadsheets with multiple pages each. I used the zip program built in to Windows as opposed to WinZip but it shouldn't matter.
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