Porsche accuses Nissan GT-R of cheating the "Ring":

[bruce.augenstein@comcast.]

Originally Posted by lucid

Footie, there is a physics-based explanation as to why the some F1 cars are faster than others. And it has everything to do with which car has the better engine, suspension, downforce, drag, and brakes, and have well the driver can explore their limits. I am not sure what your point is. Also, a 3% difference in power/weight ratio can result in a noticable difference in lap times, but I suspect the actual difference in between the first and last place cars is larger than that although I really don't know the details on that. Where did you get the 3% figure?

Of course "...there is a physics-based explanation as to why the some F1 cars are faster than others".

footie's point is that, even with controlled cars under controlled (same day, same track, same lap) conditions, there can well be significant differences in performance amounting to well over a second a minute in lap times, even with the same driver if conditions change just a little.

We've gone through this ad nauseum, and even Swamp has agreed that the GT-R in question might've done that 7:29 - with a 10% underrating, of course, which appears to be about right, based on other data.

That was and is good enough for me. If you'd like to reopen the discussion with new data, however, please do.

Bruce

[lucid]

Originally Posted by bruce.augenstein@comcast.

Of course "...there is a physics-based explanation as to why the some F1 cars are faster than others".

footie's point is that, even with controlled cars under controlled (same day, same track, same lap) conditions, there can well be significant differences in performance amounting to well over a second a minute in lap times, even with the same driver if conditions change just a little.

Sure, but my guess is that the cars are not as controlled as footie puts it although I don't have any data to back that up. I doubt that anyone has the data to begin with.

Originally Posted by bruce.augenstein@comcast.

We've gone through this ad nauseum, and even Swamp has agreed that the GT-R in question might've done that 7:29 - with a 10% underrating, of course, which appears to be about right, based on other data.

That was and is good enough for me. If you'd like to reopen the discussion with new data, however, please do.

Bruce

You also seem to agree that the car was underrated. So, there actually is no issue/reason to reopen the discussion. The only reason I responded was because someone called something I posted nonsense. The regression analysis is not proof of any kind, but it isn't nonsense either.

[footie]

Originally Posted by lucid

Footie, there is a physics-based explanation as to why the some F1 cars are faster than others. And it has everything to do with which car has the better engine, suspension, downforce, drag, and brakes, and have well the driver can explore their limits. I am not sure what your point is. Also, a 3% difference in power/weight ratio can result in a noticable difference in lap times, but I suspect the actual difference in between the first and last place cars is larger than that although I really don't know the details on that. Where did you get the 3% figure?

What I am referring to is basically the additional info required to give an accurate guesstimate, the stuff you are highlighted above now in bold. When a lap in an controlled environment like F1 can throw up a difference between 3 and 5 seconds per lap in qualifying though generally nearer the 3 second mark then it's very hard to argue a case that the GTR isn't capable of lapping the ring in 7:29 but this very basic regression model shows it not to be possible or at the very least highly unlikely.

The 3% is from a comment by Mark Blundell when a Ferrari was overtaking a back marker. I would say that this comment was a rough estimate that was either rounded up or down.

[lucid]

Originally Posted by footie

What I am referring to is basically the additional info required to give an accurate guesstimate, the stuff you are highlighted above now in bold. When a lap in an controlled environment like F1 can throw up a difference between 3 and 5 seconds per lap in qualifying though generally nearer the 3 second mark then it's very hard to argue a case that the GTR isn't capable of lapping the ring in 7:29 but this very basic regression model shows it not to be possible or at the very least highly unlikely.

The 3% is from a comment by Mark Blundell when a Ferrari was overtaking a back marker. I would say that this comment was a rough estimate that was either rounded up or down.

The basic regression model does not say anything about anything being impossible. It just says it is highly unlikely. The 3% or more variation in power/weight in F1 cars is surely contributing to the difference in lap times (you are saying that Blundell made the comment and focused on the issue as one car was overtaking another). To what extent exactly, I don't know; I haven't thought about it. It doesn't sound like you have either. If we had exact data on that, and preferably on the other variables I mentioned and that you bolded as well, we could run a regression model for that as well. In the GTR case, others tried to account for some of those other variables such as drag coefficients and skidpad values. I don't remember if braking performance was considered.

At some point, it can be argued that decomposing and analyzing performance into such categories results in error since that doesn't necessarily determine how all the parameters interact and behave as a whole, and there is merit to that argument. It's just a matter of how much of a difference that can make, and how come other manufacturers such as Porsche and Ferrari are getting it all wrong, but Nissan is getting it all right.

[swamp2]

Originally Posted by urbo73

You don't know anything about me - stop calling out names and getting so personal. The funny thing is that I have a degree in physics (Cornell, '95), AND I've raced in Formula Ford SCCA 1600/2000 ZETEC (96-99). So I'm going to say I know quite a bit about science as well as racing. People on forums should take it easy before dishing out stuff....What is your background and, more importantly, experience? I stand by what I said.

When you call good work with very insightful and useful conclusions "nonsense" you might expect a small back lash. As well you should absolutely examine the terribly hypocritical nature of your reply above. Although "nonsense" itself it not really a personal attack, when it is used in isolation with no further explanation as to WHY you think so, it does become, more or less, an attack. Hence I will say you started it... Furthermore you don't know anything about the folks who put the work together. Ph.D. in Mechanical Eng. and M.S. in Physics, the latter being myself. I think the idea was mine but member lucid actually put the first draft together. Although I have never raced cars I have driven all shapes and sizes of things with 2, 3 and 4 wheels (and tracks as well) very fast on and off road, pavement to gravel to dirt and ice all from a fairly young age.

The work in essence represents the real world statistics of F=ma, that is it. However, it also represents the fairly obvious observation that high power and low weight sports cars tend to push all of their systems simultaneously (brakes, tires, power, weight, suspension, etc.). I suppose you can feel free to continue to call the obvious "nonsense".

[lucid]

Originally Posted by swamp2

I think the idea was mine but member lucid actually put the first draft together.

T-Bone brought up a questionable relationship between power/weight ratio and the shockingly good laptime for the GTR first on this forum in response to Ruff's report of the sub 7:30 time, and you articulated that further, but I am pretty sure the regression idea to put the various numbers in context was mine. Sorry Swamp. You want to debate that?

http://www.m3post.com/forums/showthread.php?t=85724
http://www.m3post.com/forums/showthr...ht=gt-r+7%3A30

Seriously, looking back at that thread, I realized why I got involved in this to begin with. The M3 was not yet released and we were all sitting around pissed that Europeans were driving it and pretty much reading anything remotely M3 related, and the Gt-R thing popped up, and I had nothing else to do like driving my my M3. It all seems so long ago. Never thought this forum would remind me of my own aging process!

[T Bone]

Originally Posted by lucid

T-Bone brought up a questionable relationship between power/weight ratio and the shockingly good laptime for the GTR first on this forum in response to Ruff's report of the sub 7:30 time, and you articulated that further, but I am pretty sure the regression idea to put the various numbers in context was mine. Sorry Swamp. You want to debate that?

http://www.m3post.com/forums/showthread.php?t=85724

Seriously, looking back at that thread, I realized why I got involved in this to begin with. The M3 was not yet released and we were all sitting around pissed that Europeans were driving it and pretty much reading anything remotely M3 related, and the Gt-R thing popped up, and I had nothing else to do like driving my my M3. It all seems so long ago. Never thought this forum would remind me of my own aging process!

Sorry guys, I have been fighting the ecomony so I missed the repost.

• There was speculation that Nissan underrated the GTR's power - which the motortrend article dispelled for a production car.
• There was an admission that Nissan used beta software for the ECU when the ran the sub 7:30 time.
• The regression analysis showed a low probability of a 7:30 time given the power / weight ratio
• Add all this up and something stinks in Denmark

So at the risk of asking something that has been posted..... How many standard deviations is a 7:30 time for a car with the GTR's power to weight ratio?

[southlight]

Originally Posted by lucid

Seriously, looking back at that thread, I realized why I got involved in this to begin with. The M3 was not yet released and we were all sitting around pissed that Europeans were driving it and pretty much reading anything remotely M3 related, and the Gt-R thing popped up, and I had nothing else to do like driving my my M3. It all seems so long ago. Never thought this forum would remind me of my own aging process!

Showing your true colors now.


Best regards, south

[lucid]

Originally Posted by southlight

Showing your true colors now.

You guys always get the goodies first!

[southlight]

Originally Posted by lucid

You guys always get the goodies first!

Trying to come BTT: So you wouldn't consider the GT-R being a goodie?


Best regards, south

[lucid]

Originally Posted by southlight

So you wouldn't consider the GT-R being a goodie?

You want to re-start the war? The funny thing is I actually don't really care about the GTR's laptime. It's clearly a great car, and it might be lapping at 7:20 for all I care. All the power to it!

[southlight]

Originally Posted by lucid

You want to re-start the war?

In no way! It was just the first car with a delayed European launch that came to my mind...


Best regards, south

[urbo73]

swamp2/lucid - chill out guys. You guys sound like this is an attack on a thesis - don't remind me of those days. It's not. It's a thread on the Internet...I didn't feel like typing 10 pages in my reply - sorry if being curt was an insult. It wasn't meant that way at all - judge me from other posts here if you want. You guys are taking it the wrong way, really...

This whole thread to me is nonsense in the sense that to me it's somewhat foolish, has very little importance, and is of no real use based on the little, real data which exists that you can use for anything you're trying to prove or disprove. The debate will go on and on, and on, and on. There is little to work with here, unless we get a Nissan engineer involved, etc. Basing all of this on the simple things you know/mention is not enough to draw any real conclusions from - not for me at least. It's not the approach - it's what your working with (very little - too many unknowns). Porsche spent a lot of money trying to do the same. Were/are they right? I'm not sure. And I like Porsche as a company and their cars (see my posts in this forum), and can care less about the GT-R. But I have my doubts r.e. Porsche too. I don't like their tactics here. And you can bet they did a ton of analysis - more than in this thread...Hell, they should get Patrick Long in their cars to set the times at the Ring. Give him 100 laps to learn it, and let him loose. They'll have better times than with Rohrl. This investigation business - just looks bad to me. Maybe it's just me, as much as I love them. Why bad? Because no matter what, they can't convince anyone any differently. It's not something that they can prove or disprove if you see what I mean.

The other thing I said is that there are people who measure and people who drive. You don't know the number of times I've had people "demonstrate" to me how this corner at this track, etc. can be taken at max xxx/mph because of this and that. That the braking distance is such and such, etc. I could go on. But many times only to prove them wrong when I actually drove. Sometimes you just gotta put that analysis to bed and just drive. That's all. My background is the same, physics/engineering, but I had to put a lot of that behind me in many cases. Why? Because it can be inhibiting. If someone told me that I can only do this lap in x amount of time, take this corner at x/mph, etc., because of this and that, and if I really got into that analysis myself, I would believe it and not push as hard as I would otherwise. It's something that's hard to explain. When you know of a limit and believe in it, you fall victim to it many times.

I realize I was brief and curt and was talking a bit in general too. My mistake perhaps. I've had lengthy discussions before that went nowhere, so I try sometimes to be curt on purpose at times. But on the Internet it backfires too many times. It's the nature of it, since as I said you don't know me, I don't know you, etc. I forget at times, I know. I expect people to know me for some reason. It's a silly notion, I know.

Anyhow, peace!

PS I just missed the last 7-8 posts while typing this.

[urbo73]

Originally Posted by lucid

Seriously, looking back at that thread, I realized why I got involved in this to begin with. The M3 was not yet released and we were all sitting around pissed that Europeans were driving it and pretty much reading anything remotely M3 related, and the Gt-R thing popped up, and I had nothing else to do like driving my my M3. It all seems so long ago. Never thought this forum would remind me of my own aging process!

There you go - what I meant with measuring vs. driving..

[T Bone]

Originally Posted by lucid

You want to re-start the war? The funny thing is I actually don't really care about the GTR's laptime. It's clearly a great car, and it might be lapping at 7:20 for all I care. All the power to it!

I love the GTR but fair play is fair play and this is why this discussion is a good one.

Do you have a valid sampleset to see how rare a 7:30 time is for a car like the GTR?

[lucid]

Urbo, ultimately, yes, there is no way to prove or disprove the claim. The car that ran that lap had to be preserved and tested for that to happen. And since that's not the case, it is indeed not possible to be absolutely sure about either position.

I wouldn't take various people's opinions about how fast the car should be driven here or there either because they are various people at the track. But for instance, there is no question that F1 cars can go as fast as they go because of all the built-in instrumentation, telemetry, and the resulting measurements that are analyzed and utilized to increase performance, so as we all seem to agree, the approach is fundamentally sound. It sounded like you were bashing the approach, and that's what prompted the nerdy responses. BTW, I would clearly put more stock in the analysis outcome than you do, but that's an interpretation issue, which is not worth debating at this point.

Anyway, as I recall, you are local, and maybe I'll run into you driving around one day or at a local track. Cheers.

[lucid]

Originally Posted by urbo73

There you go - what I meant with measuring vs. driving..

You got me there man!

[lucid]

Originally Posted by T Bone

Do you have a valid sampleset to see how rare a 7:30 time is for a car like the GTR?

I can't find my regression spreadsheet (oh NO!) It's either on a computer at home or lost. I'll check later.

[T Bone]

Originally Posted by lucid

I can't find my regression spreadsheet (oh NO!) It's either on a computer at home or lost. I'll check later.

Ah!! NO!!!

[footie]

Lucid,

Is it the list of cars on the regression or the formula?

Swamp sent me the list but I didn't keep it.

[urbo73]

Originally Posted by lucid

Anyway, as I recall, you are local, and maybe I'll run into you driving around one day or at a local track. Cheers.

Yes - here in warm Boston There was another guy if I remember as well. Boston folks not very organized! Still got my snows on. Let's wait until it gets warmer. I'm leasing my M because it's a temporary car until I can get back into a 911 in 2.5 years (yes I'm counting). By that time, my son will be big/old enough for just a small booster that can easily fit in the back of a 911. He'll be able to hop in/out with ease. But for now I need the M3 sedan - that's my compromise. Promise I made to the wife. I'll have to decide how much I want to beat up on a leased car at the track...I sort of got that out my system a long time back. Just recently my wife is allowing me to even *think* about the occasional SCCA race in my old FF car that I have to re tune. It's been a while. I would like to go to the Road America's 40th this summer and race it there. I'll see. Getting completely off topic now!

[urbo73]

Originally Posted by footie

Lucid,

Is it the list of cars on the regression or the formula?

Swamp sent me the list but I didn't keep it.

Oh, oh!!! Looks like someone is not going to get their dissertation approved!