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

[lucid]

As if they don't test cars before they release them to distribution to see if the variability is within "norms." Hand assembly will not yield +/- 10% variability in (significant) engine output. Those technicians are pros. If that was the case, they would halt production and try to figure out what's wrong. You are not going to have a 530hp car randomly coming out of the Nissan assembly line when the spec is 480hp to due some huge variation you see to claim exists. That would get people fired.

[TLud]

Originally Posted by oneginee

...the performance of manufactured part will follows a normal distribution. By taking only the best parts the manufacturer can assemble a special bred "stock" test car for the ring...

I understand the concept of a normal distribution; my point was that no one yet knows what the norm is for the GTR. The tests have been so wildly different, that they all appear to be statistical outliers. Which "outliers" are the real thing?

I also understand (and I think someone was trying to make this point in reference to Ferrari) that you'll have much more divergence in performance between two identical cars at this level. A few percentage points of variance can mean a big difference in power.

However, at best, Nissan's reporting of output and performance numbers for the GTR has been questionable. That to me is troubling, especially given the fact that so many are buying sight unseen in reliance on these numbers. And before anyone states that Ferrari and Lambo owners buy sight unseen every day, we're talking about a $90,000 Nissan here.

[T Bone]

Originally Posted by oneginee

the performance of manufactured part will follows a normal distribution. By taking only the best parts the manufacturer can assemble a special bred "stock" test car for the ring.

Actually, the biggest issue that I see is the apparent variant in GTR power output.

If we can agree that variability is NOT good then something is amiss in Nissan quality control. (or any car company that delivers a wide variance - I don't know what Footie is talking about in the F430s.)

Also with a turbo car, much of the performance is directly dependent on the ECU programming. Is there any information on software revision for all these GTRs?

[bruce.augenstein@comcast.]

Originally Posted by T Bone

Actually, the biggest issue that I see is the apparent variant in GTR power output.

If we can agree that variability is NOT good then something is amiss in Nissan quality control. (or any car company that delivers a wide variance - I don't know what Footie is talking about in the F430s.)

Also with a turbo car, much of the performance is directly dependent on the ECU programming. Is there any information on software revision for all these GTRs?

I've also been troubled by this phenomenon. Car & Driver, in particular, has tested a couple of relative dogs. As far as I know, the test range has run quarter miles from around 11.5 seconds all the way up to 12.6 (including Car & Driver), with trap speeds from 111 mph all the way up to 124+. I personally discount that 124 mph report from C & D, largely because they show a correction factor (due to testing at a 4000 foot altitude) that just shouldn't be there, since as far as I know Nissan compensates turbo boost for altitude. However, that still leaves a range that is just too high for a modern era vehicle.

Nissan told C & D that they were working a number of different tuning parameters on the early U.S. spec cars, and that in fact may explain it, since test vehicles supplied to magazines after that have kind of settled in the high eleven second, 120 mph range. Doing the arithmetic on that gives power estimates close to 10% higher than Nissan states though, along with at least a couple of dyno tests that seem to indicate the same thing. When you add the fact that Nissan has apparently skipped the SAE power certification process on the car (and admittedly all their other cars), it's hard to think anything else except Nissan has underrated the car for some reason. The tempest in a teapot elsewhere in this venue seems to center on whether the car needs "only" 520-530 Hp to get around the 'Ring in 7:29, or as much as 550 HP.

Gee, big deal.

Bruce

[swamp2]

Originally Posted by bruce.augenstein@comcast.

The tempest in a teapot elsewhere in this venue seems to center on whether the car needs "only" 520-530 Hp to get around the 'Ring in 7:29, or as much as 550 HP.

Wholeheartedly agree! Finally...

There is the

"530 hp
+great tires
+factory "tweaks" still within specs
+DCT
+ace driver
+great AWD system
+favorable track conditions
+time hundreds of laps until you are blue in the face and take the best
+etc."

argument

And this agrument has merit. I just wish the GT-R wasn't so darn fast on the straights. Then the above could win me over.

[swamp2]

Originally Posted by oneginee

Disagreed. Nissan is quite detailed about the specs of the car. The norm for the GTR is whatever Nissan can achieve while still being held to these specs.

Hmmm I don't see and +/- on the hp nor torque. Not comments about "at altitude, etc.

Originally Posted by oneginee

the performance of manufactured part will follows a normal distribution. By taking only the best parts the manufacturer can assemble a special bred "stock" test car for the ring.

Firmly disagree and agree with Tlud and Lucid on this one. 10% hp is way too much to happen in any modern automobile, hand assembled or not. The precision, tolerances, repeatability and statistical control in such environments is unreal.

Originally Posted by oneginee

... until there is proof of unfair modifications of that GT-R all I can conclude is:

1. The german Porsche do not have the same level of yield and manufacturing quality control as the japanese do
2. the GT-R design engineers outranked the germans

Wow, talk about speculative and without proof. Unreal. Please provide one shred of evidence for either of these claims. You can't because they are imprecise and for the most part unsubstantiatable, especially #2. Don't you realize how fan boy-ish such statements sound?

[footie]

Originally Posted by T Bone

Actually, the biggest issue that I see is the apparent variant in GTR power output.

If we can agree that variability is NOT good then something is amiss in Nissan quality control. (or any car company that delivers a wide variance - I don't know what Footie is talking about in the F430s.)

Also with a turbo car, much of the performance is directly dependent on the ECU programming. Is there any information on software revision for all these GTRs?

If you are such a big fan of all things M5Board, especially the videos I would have thought you would have seen this.

Read the opening lines.

[lucid]

Originally Posted by footie

If you are such a big fan of all things M5Board, especially the videos I would have thought you would have seen this.

Read the opening lines.

Taking an F430 to the drag races. A dumb thing to do IMO. Anyway, footie, there can be many reasons why that red F430 is not as fast as the black one, and I bet it has nothing to do with how they came out the factory. We went over this before: there is no way of knowing if the cars are indeed stock or modified in the same way if modified, driver could be shifting early falsely thinking redline will damage his engine or the optimum shift point is somewhere else (I'll discount slow shifts since these are automated), tire type/temp/wear, potential abuse/driving historty, etc. I am sure Ferrari dynos these cars before they are released to delivery. Small productin numbers at a company like Ferrari means even higher quality control. They don't want one F430 being significantly faster than another out the door. That doesn't serve their interest. People pay big bucks to acquire these machines, and one would be pissed to learn someone else's F430 was significantly faster on delivery.

[footie]

Lucid,

I don't know if the Black F430 was tuned or the driver happened to be more gifted. All I was saying was that it's difference was noted by the organisers.

Of all the GTRs that have been tested this side in the UK, when the car hasn't produced the times expected there has been a reason, be it the clutch had been abused or something else. But there is enough evidence out there to assume the GTR in stock form is producing more than quoted, be it from dyno results or acceleration figures.

That has always been my point about the 7:29 lap, the car is producing more than quoted but then all of them are and the explanation that swamp is using in the other thread is obsurd, especially when you look at the entire lap and see that on other area the ZR1 shows the kind of acceleration difference one would expect.

[T Bone]

Originally Posted by footie

If you are such a big fan of all things M5Board, especially the videos I would have thought you would have seen this.



Read the opening lines.

I don't understand your point. What does Ferrari variance have to do with GTR power variance.

Ferrari hand builds engines which will, on balance, deliver more variance than engines that are built by machine / robots (like the M engines)

So variance in Ferraris isn't too surprising for me.

Back to the GTR, I wished we would track power vs. software revision.

[lucid]

Originally Posted by T Bone

Ferrari hand builds engines which will, on balance, deliver more variance than engines that are built by machine / robots (like the M engines).

Not really. It's not as if the Ferrari techs use sandpaper and manual milling machines and lathes and eyeball the cam surface when machining a camshaft or any other precision part. It's all done by CNC equipment. They just simply "assemble" things by hand, which means they put things together, but machining tolerances dictate how well things fit together, not something the tech does. The tech can do a blatant mistake and misassemble something (applying the wrong torque to fasten a bolt) or use the wrong profile when machining a part, but that would be caught, and I doubt that those guys make too many blatant mistakes of that nature. If your volume is low, you can control variance in your manufacturing processes really well as long as you actually don't "build" any parts by hand. Again, I doubt that Ferrari builds any engine components by hand. Plus, I believe M engines are also hand assembled.

[T Bone]

Originally Posted by lucid

Not really. It's not as if the Ferrari techs use sandpaper and manual milling machines and lathes and eyeball the cam surface when machining a camshaft or any other precision part. It's all done by CNC equipment. They just simply "assemble" things by hand, which means they put things together, but machining tolerances dictate how well things fit together, not something the tech does. The tech can do a blatant mistake and misassemble something (applying the wrong torque to fasten a bolt) or use the wrong profile when machining a part, but that would be caught, and I doubt that those guys make too many blatant mistakes of that nature. If your volume is low, you can control variance in your manufacturing processes really well as long as you actually don't "build" any parts by hand. Again, I doubt that Ferrari builds any engine components by hand. Plus, I believe M engines are also hand assembled.

Gonna have to disagree here. I would much preferred machine / robot built stuff these days rather than hand built.

I see your point if the parts are very tight in tolerance.

Would you prefer hand torquing or machine torquing?

[footie]

All of them (Ferrari, Porsche, Nissan GTR, BMW M-Division, etc) manufacturer the parts robotic-ly but they are all assembled by hand. Each engine will be tested on a rig and should all meet a standard within an acceptable level, the one thing I do know is that no engine can be below a certain level of output, but I'm unsure if they stop an engine going out into supply if it over exceeds these figures.

I reckon all of them (manufacturer) hand pick examples which go to the motoring press and are used in testing like the ring, but believe these engine lay within a certain envelope of what is normal for one to buy out of a dealers. They will be at the upper level but doubt if they will exceed this.

[lucid]

Originally Posted by T Bone

Gonna have to disagree here. I would much preferred machine / robot built stuff these days rather than hand built.

I see your point if the parts are very tight in tolerance.

Would you prefer hand torquing or machine torquing?

We'll have to agree to disagree on this one. As Footie has said, these engines are all assembled by hand. I don't know if a truly mass produced engine is assembled via a fully automated process either--I doubt it.

[T Bone]

Originally Posted by lucid

We'll have to agree to disagree on this one. As Footie has said, these engines are all assembled by hand. I don't know if a truly mass produced engine is assembled via a fully automated process either--I doubt it.

Disagreement in a healthy / respectful way is always good

Of course automation is a scale for all modern cars. When I saw the ultimate factories documentary on NGC, I saw alot of hand assembly at Ferrari's Modena factory vs. the BMW factory where it appeared to have more automation.

Things like tolerances / torquing, I would much more prefer to have automation versus a hand process.

[footie]

Originally Posted by T Bone

Disagreement in a healthy / respectful way is always good

Of course automation is a scale for all modern cars. When I saw the ultimate factories documentary on NGC, I saw alot of hand assembly at Ferrari's Modena factory vs. the BMW factory where it appeared to have more automation.

Things like tolerances / torquing, I would much more prefer to have automation versus a hand process.

There are things we do know about engine production in these major companies. AMG assemble all engines by hand, the same is true for M-Division engines. I can't only assume that Porsche and Ferrari do something similar and that Nissan openly state how their GTR is built.

Many would say that hand assembly should meet higher standards as mass produced stuff generally aren't as precise because no one is watch each part being assembled. Does this mean finer variations?, you would think so but I have witnessed two identically built Cosworth BDA engines producing marked differences in performance so I believe there will always be variations unless plans are put into place to stop this, like is present in Ford Renault and other single make series racing.

I reckon the early samples where the GTR was showing wide variation will have all but stopped now.

[footie]

These figures are from Motortrend's latest.

0-60 mph
ZR1 3.3s
599 GTB 3.2s
GTR 3.2s
GT2 3.4s

0-100 mph
ZR1 6.9s
599 GTB 7.1s
GTR 8s
GT2 7.3s

Quarter mile
ZR1 11.2 sec @ 130.5 mph
599 GTR 11.3 sec @ 126.4 mph
GTR 11.6 sec @ 120.0 mph
GT2 11.4 sec @ 127.9

All figures which are consistent with the kind of power the GTR is believed to have.

[swamp2]

Originally Posted by footie

That has always been my point about the 7:29 lap, the car is producing more than quoted but then all of them are and the explanation that swamp is using in the other thread is obsurd, especially when you look at the entire lap and see that on other area the ZR1 shows the kind of acceleration difference one would expect.

Keep it in the right thread.

You still have not produced a single argument against the analysis other than "my eye is better" or "it looks like" or "it is my opinion" or "in the curvy sections of the track". You can disagree with my analysis but you should have a good reason and you clearly don't. Calling the estimate obsurd [sic] is massive exaggeration. Your guess of 10% and mine of 550 hp are only 5% apart!

Wind, grade, temperature and other environmental conditions are absolutely factors that would contribute to inaccuracies in the analysis, but as I have said, time and time again, those can be added and I am willing to adjust if we learn new facts or even likely possibilites. The problem is that it is nearly certain we will never know the values to use, hence educated and reasonable guesses are required.

[ismelllikepoop]

Originally Posted by swamp2

Keep it in the right thread.

You still have not produced a single argument against the analysis other than "my eye is better" or "it looks like" or "it is my opinion" or "in the curvy sections of the track". You can disagree with my analysis but you should have a good reason and you clearly don't. Calling the estimate obsurd [sic] is massive exaggeration. Your guess of 10% and mine of 550 hp are only 5% apart!

Wind, grade, temperature and other environmental conditions are absolutely factors that would contribute to inaccuracies in the analysis, but as I have said, time and time again, those can be added and I am willing to adjust if we learn new facts or even likely possibilites. The problem is that it is nearly certain we will never know the values to use, hence educated and reasonable guesses are required.

it seems like that's the only kind of analysis anyone is really doing here anyways. watching youtube videos and using "science" is not really a legitimate way of explaining a car's track time, it's not like the ring is in a bubble. either way i have no idea why i keep looking at these threads.

[T Bone]

Originally Posted by swamp2

Keep it in the right thread.

You still have not produced a single argument against the analysis other than "my eye is better" or "it looks like" or "it is my opinion" or "in the curvy sections of the track". You can disagree with my analysis but you should have a good reason and you clearly don't. Calling the estimate obsurd [sic] is massive exaggeration. Your guess of 10% and mine of 550 hp are only 5% apart!

Wind, grade, temperature and other environmental conditions are absolutely factors that would contribute to inaccuracies in the analysis, but as I have said, time and time again, those can be added and I am willing to adjust if we learn new facts or even likely possibilites. The problem is that it is nearly certain we will never know the values to use, hence educated and reasonable guesses are required.

In watching the video, it became apparent the driver on the fast lap was an ex-F1 dude.

I think the biggest factor will be driver.

Look at the CTS-V vs. M5 discussion. Heinracy (GM) vs. Auberlin (BMW) and the cars came out well less of 1 second per lap.

If we put someone like a Senna, Schumacher, Massa into the cockpit of the 911 Turbo, it would encroach on Supercar times even driven by very capable drivers.

Driver / Conditions would be my "guess" at the most influential factor on lap times.

[lucid]

Originally Posted by T Bone

In watching the video, it became apparent the driver on the fast lap was an ex-F1 dude.

I think the biggest factor will be driver.

Yes, he is Toshio Suzuki. His glory days are well behind him, but still. I brought this up a few months back, but it didn't get any attention. I am pretty sure Nissan stated that Suzuki is 15 seconds faster than their 2nd driver.

[1º]

who cares about these lap times?
does it really matter to any of you?
do you guys buy cars based on how fast the go around the ring?
how many of you will actually drive your car around the ring? let alone on any track?
and if you do, how many of you will get even close to the times that have been stated?