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      12-16-2007, 03:16 PM   #67
Voltigeur
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Quote:
Originally Posted by Champagne View Post
What I've been saying all alone is that I'm not going to live with a car that my gut doesn't like because of two rental brake downs. What's so terrible with me leaving my own personal opinion about Nissans? I've had a couple of bad experiences with a specific brand, and I don't want to live with a car with that badge on it.

That's all I've been saying all along.
Nothing terrible - you are entitled to your opinion. All they are suggesting - which as an econometrician I can agree with - is that 2 rentals do not make a statistically valid sample for extrapolating reliability for the brand. Nor does owning 2 or 3 Nissans and having no issues. One has to go rely more on large sample surveys for more reliable inferences, not subjective opinions (this is not directed at you - but applies to all our "feelings" towards cars that we have owned / rented).
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      12-16-2007, 03:52 PM   #68
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swamp,

There is a lot of speculation going on with very little evidence at all.

Sorry to sound so blunt about the fact.
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      12-16-2007, 04:04 PM   #69
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I'm going to chill and wait for the CAR / EVO / C&D test
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      12-16-2007, 05:59 PM   #70
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I KNOW the numbers are bogus...explain this...

nissans rating
480 hp @ 6,800 rpm... 430 lb-ft torque @ 3,200 - 5,200 rpm.
59.2 kilogram meter = 428.1944188307 pound foot

isn't it a heck of a coincidence that the two dyno numbers match nissans ratings almost perfectly? 482 vs 480 HP and 428 vs 430 ft lb ...hmmmmmm

also at 5250 HP = Torque, the lines cross...
HP ~ 465 or so...
T ~ at peak 426 or so...
they don't match...hmmmmmmm

but wait, they HAVE to match HP = rpm/5250 x T...at 5250, HP = T...period...

they also state max torque of 430 from 3200 to 5200
peak T is only 4700 to 5200, well shy of the claimed

oh yea, claimed HP peak is 6800, this is ~6100...

it's off everywhere...

rpm.....dyno T......dyno HP.....calculated HP
3000....130.............60...............74
4000....330............275.............251
5000....428............440.............408
6000....380............480.............434


the ratio window (4.660) should be 1.248 x 3.7 ~ 4.618...4th gear run...

dyno speed at T peak 78 mph/5130 rpm...but calculated speed using the ratios is 91
dyno speed at HP peak 92 mph/6115 rpm...calculated is 108...

this, and the HP/T mismatch at 5250 screams rigged...
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      12-16-2007, 06:11 PM   #71
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Quote:
Originally Posted by ArtPE View Post
this, and the HP/T mismatch at 5250 screams rigged...
But who is doing the rigging.
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      12-16-2007, 06:35 PM   #72
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Quote:
Originally Posted by ArtPE View Post
I KNOW the numbers are bogus...explain this...
Yes, the TQ and HP graphs don't match, but we don't know if they are from the same runs.

Explain the performance numbers without numbers similar to what they are showing.
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      12-16-2007, 06:40 PM   #73
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Well sure if they were from different dyno runs that would make matters worse because it would be saying that Nissan quality control was out the window, two engine offering totally different results.
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      12-16-2007, 07:01 PM   #74
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Originally Posted by sdiver68 View Post
Yes, the TQ and HP graphs don't match, but we don't know if they are from the same runs.

Explain the performance numbers without numbers similar to what they are showing.

why would they do that...even if they could...
btw: the file number at the bottom is the same....and these aren't print-outs, it's a real time screen shot...

iirc dynos CAN'T measure HP...they measure torque and covert it to HP...
so which is right? the HP or the torque...

they are BOTH wrong, I'm guessing torque is 10% high...and the HP curve is complete BS...the data was manipulated between the torque readings and HP calcs/display...don't ask how I deduced this...I'm pretty sure it's close...

adjusted...less 10% T
rpm.......T.......HP
3000....117.....67
4000....300.....226
5000.....385....367
6000.....380....391

this would give a power loss of (480-391)/480 x 100 = 18.5%
that's a good number for an awd car with high drive rations (Fd = 3.7)


that's the point...
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      12-16-2007, 07:41 PM   #75
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Quote:
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swamp,

There is a lot of speculation going on with very little evidence at all.

Sorry to sound so blunt about the fact.
Blunt is fine, confused/mistaken is not. If you are still talking about shift times I say BS. You need to get over my appropriate criticism of your past speculation, keep that on that thread and stop tyring to simply turn the tables here. I provided lots of real and accurate actual data along with semi-subjective reviews from journalists about the "feel" of each tranmission, combined with my direct experience with SMG II which pretty much matches what everyone say/knows about that system. I would like a chance to address anything you believe to be speculation (I think I already have done so by the way, but if not, I will keep going).
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      12-16-2007, 10:09 PM   #76
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OK first of all MASSIVE and in all caps may have been a bit dramatic/overstated, maybe even a bit premature. There is, however, multiple forms of evidence pointing to an under-rating. Part of the reason for my word choice was based on the dyno results showing basically the claimed crank output at the wheels. I was a bit short sighted on the subtleties of that particular dyno in that it typically gives figures much higher than other dynos. However, even if it rates things about 10% too high with a 20% total drivetrain loss, the GT-R still comes in at 530+ crank hp, and I guess I would still call that massive. The N'Ring regression analysis also points to the possibility of a fairly substantial under-rating (or a variety of other effects working in tandem such as great driver+DCT+great tires ... or alien technology of you prefer that explanation ...). The last piece of evidence is the 1/4 mi time and it too point to under-rating (the number I have heard is 11.7s). I'm not sure how much more evidence we will need.

Back to the simulations. Getting fantastic agreement from a simulation vs. test results may happen but it may also be a case of getting it right for the wrong reasons. I'm fairly sure this is the case for your 911 Turbo results. If Q. Jr. can predict RWD times in a reasonably well validated fashion and it has absolutely no wasy to account for AWD, then it simply (almost by definition) can not also get AWD performance figures accurate for the right reasons. Doesn't this make fundamental sense? We all know and understand that AWD cars get a harder launch but then suffer much greater parasitic drivetrain losses which hurts the cars performance more at higher speeds. You can not just rely on a simulation tool blindly and rely on it as a black box to just turn the crank, get the answer and not question the results in any way. It appears that this is what you are doing here. "Responsible" and intelligent use of simulation DEMANDS contstant questioning of the model, the inputs and results. CarTest offers complete control of a huge number of input variables including FWD, RWD, AWD and a plethora of other user defined inputs (you can see some screen grabs of the amazing number of inputs possible in CarTest on other threads here on the forum). One reason I am a bit hesitant to use and post results for cars like the 911 and GT-R is that I have not had great luck simulating Turbo charged cars yet. I will probably work a bit more on the 335i and making sure I can get good results for known/justifiable reasons before relying on CarTest too much for such cases. In any case I think my preliminary runs with CarTest for the GT-R showed it required about 520 hp to get a 3.5s 0-60 and 11.7 1/4 mi. I did use very short 0.03 s shifts as we can expect from its dual clutch system and of course the AWD option.
First of all, let's agree on terms. You have no evidence at all. None. Neither do I, for that matter. What we have are data points that may give us an inclination - or not, when taken together.

- I contend that the dyno test is an unknown quantity. We don't know about the dyno, we don't know about the particular car (chipped or not, for instance), and though I haven't glanced at the results myself yet, now it seems that there may be an issue with the validity of everything about that test.

- The 'Ring test isn't indicative of anything I can think of other than it's a flyer. The car may be naturally fast (more on that in a minute), or in fact the car may be under-rated.

- And for quarter mile times? I think they're pretty much spot on where they ought to be.

When I simulated the GT-R and came up with results that were very close to spot on (according to Nissan's numbers), that was kind of interesting. When you reminded me of the drivetrain differences (properly, I thought), I ran the Porsche not to somehow validate the tool, but to find out how the Porsche simulation would also turn out. Obviously, if it too came out pretty much spot on (which it did), then looking at the compared results makes sense, since both cars have awd with the resulting penalties.

Result? The Porsche was faster then the GT-R in the standing quarter mile (by a tenth and a single MPH), and if you do power to weight, it should've been two tenths and two mph faster. Wow! That's a whole tenth and one MPH those Nissan bastards aren't owning up to.

But wait! The Nissan has the hot-damn trans and the Porsche (equipped with the "better" of its two inferior choices) has a damned torque-converter automatic, which we know (especially you) takes power to run.

The fact that these cars are so close, with the Porsche being a little faster according to Car & Driver vs Nissan marketing, should give you pause, Swamp.

On to the 'Ring. My contention is that the GT-R is a superior handler compared to the Porsche Turbo, and while everyone on the planet hasn't tested the GT-R yet, those who have think the handling is the best part about it, while we *know* what test drivers think of the Porsche at ten tenths. My favorite quote is "It takes three feet to driver a Porsche Turbo fast." OK, the current 911s are the best ever, but they still wield the threatening sword of physics at ten tenths. The Nissan is nearly as fast in a straight line (probably due to its transmission), but definitely quicker in the twisties. It turns out the Nissan is a little quicker around the 'Ring, and I'm guessing that while it was undoubtedly very exciting during those laps, it was very relaxed compared to the Porsche Turbo. My guess is that the legendary Rorhl ran up a dry cleaning bill during that 7:40 pass.

Then there's the Edmunds article, which waxed poetic about GT-R handling, but declared the Porsche to be quicker in a straight line (out on the street) in side by side and follow the leader runs. The Porsche could not keep up in the twisties, but was the quicker car in a straight line.

Swamp, why doesn't that give you pause. The Porsche should be mildly quicker in a straight line and apparently it is.

As for your CarTest runs, I have trouble with giving them any credibility at all just yet. However, I'm betting that if you run the Porsche, it will be a bit ahead of the Nissan, just as in my simulations, but you'll also show the Porsche as being under-rated.

Finally, there's that whole SAE thing. Almost certainly, the Nissan will show "correct" numbers on the dyno or the SAE will throw them out - and of course if you're correct then the GT-R will be a comparitive pig when our magazine guys give it a run. Won't happen, though. I'd bet quite a bit that the SAE numbers have already been run under current (SAE representative present) rules.

Nissan is not only betting at least a couple of decades of legendary performance by past iterations of their baby, they're also betting that the car will be a worldwide legend, or the entire Japanese car industry loses face.

Remember "The Usual Suspects"? "A legend isn't a legend if it doesn't die."

Nope. The data points we've discussed collectively point to the fact that the jury is still out. Personally, I think the Nissan will be on the up and up, but we'll see.

Bruce
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      12-16-2007, 10:32 PM   #77
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the 997TT never ran a 7:40...

Walter 7:49
7:54 --- 156.456 km/h -- Porsche 997 Turbo, 480 PS/1620 kg (sport auto 06/07) http://www.supercars.net/PitLane?vie...D=2&tID=126501

both on PSC's

there is no way a car weighing 300 lbs more with 15% less torque on street tires can beat those times in the wet by 11 to 15 sec.

as I have shown those dyno numbers can not be true...CAN NOT...
T (lb ft) must equal HP (SAE) at 5250... MUST!!!
yet T=428 and HP = 460...
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      12-17-2007, 03:52 AM   #78
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Quote:
Originally Posted by bruce.augenstein@comcast. View Post
First of all, let's agree on terms. You have no evidence at all. None.
Maybe semantics here Bruce (or very non standard word use on your behalf). Evidence is not synonymous with irrefutable evidence. Your statement, in light of the evidence could not be much more inane. Now that this is clear as daylight lets discuss the evidence.

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Originally Posted by bruce.augenstein@comcast. View Post
- I contend that the dyno test is an unknown quantity. We don't know about the dyno, we don't know about the particular car (chipped or not, for instance), and though I haven't glanced at the results myself yet, now it seems that there may be an issue with the validity of everything about that test.
We know something about the dyno, perhaps you missed post #4 by jworms which I already referred to? Time to read. This dyno has read about 10% higher on his car compared to a more familar dynojet dyno. RWHP that is 10% too high but is already equal to claimed hp works out to be about 13% higher than the wheel value at the crank (just .9/.8, using 20% loss). This brings us right back to 50 or so hp under-rated.

Quote:
Originally Posted by bruce.augenstein@comcast. View Post
- The 'Ring test isn't indicative of anything I can think of other than it's a flyer. The car may be naturally fast (more on that in a minute), or in fact the car may be under-rated.
Holy self-contradictions, a mere one sentence apart. Do you even read what you write? Can you make up your mind?

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Originally Posted by bruce.augenstein@comcast. View Post
When I simulated the GT-R and came up with results that were very close to spot on (according to Nissan's numbers), that was kind of interesting. When you reminded me of the drivetrain differences (properly, I thought), I ran the Porsche not to somehow validate the tool, but to find out how the Porsche simulation would also turn out. Obviously, if it too came out pretty much spot on (which it did), then looking at the compared results makes sense, since both cars have awd with the resulting penalties.

Result? The Porsche was faster then the GT-R in the standing quarter mile (by a tenth and a single MPH), and if you do power to weight, it should've been two tenths and two mph faster. Wow! That's a whole tenth and one MPH those Nissan bastards aren't owning up to.

But wait! The Nissan has the hot-damn trans and the Porsche (equipped with the "better" of its two inferior choices) has a damned torque-converter automatic, which we know (especially you) takes power to run.

The fact that these cars are so close, with the Porsche being a little faster according to Car & Driver vs Nissan marketing, should give you pause, Swamp.
I don't think my sims nor yours are particularly strong here. So let's put those aside for now. I have admitted why mine are only so-so, however, you will not yet seem to admit the most basic truth about Quarter Jr. and your application of it, clearly and irrefutably highlighted in my previous post - the AWD issue. This makes your sims right for the wrong reasons. You simply can not tout the accuracy of the software for RWD and AWD cases when all logic and common sense tells you it can not get both correct for the right reasons.

One example of dyno runs I have seen for the 997 Turbo are here (just from a quick google). They give 429 hp/457 tq and if you believe the manufacturers claimed outputs this gives a drivetrain loss for hp at 11% and tq at a mere 4%. Possible or not, you tell me? I'd say this is some fairly good evidence of under-rating here as well, this would also be somewhat consistent with your QJ runs allowing for the higher drivetrain loss being balanced by the under-rating.

Quote:
Originally Posted by bruce.augenstein@comcast. View Post
On to the 'Ring. My contention is that the GT-R is a superior handler compared to the Porsche Turbo, and while everyone on the planet hasn't tested the GT-R yet, those who have think the handling is the best part about it, while we *know* what test drivers think of the Porsche at ten tenths. My favorite quote is "It takes three feet to driver a Porsche Turbo fast." OK, the current 911s are the best ever, but they still wield the threatening sword of physics at ten tenths. The Nissan is nearly as fast in a straight line (probably due to its transmission), but definitely quicker in the twisties. It turns out the Nissan is a little quicker around the 'Ring, and I'm guessing that while it was undoubtedly very exciting during those laps, it was very relaxed compared to the Porsche Turbo. My guess is that the legendary Rorhl ran up a dry cleaning bill during that 7:40 pass.
If you read much of the N'Ring regression post you would have learned by now that the vast majority of a cars time is simply due to power to weight ratio. On a very tight, lower speed course or something like an autocross handling, weight and skidpad results will be more important but on the N'ring it is mostly about acceleration in the straights and the near straights. We already know that the GT-Rs ace driver, DCT tranny and likely near race compound street tires are definitely responsible for a lot of its great lap time. Could these without and under-rating let it achieve that time? That is the big question.

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Originally Posted by bruce.augenstein@comcast. View Post
Then there's the Edmunds article, which waxed poetic about GT-R handling, but declared the Porsche to be quicker in a straight line (out on the street) in side by side and follow the leader runs. The Porsche could not keep up in the twisties, but was the quicker car in a straight line.

Swamp, why doesn't that give you pause. The Porsche should be mildly quicker in a straight line and apparently it is.
Sure, and then there is that pesky/likely 997 Turbo under-rating issue as well. See above...

Quote:
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As for your CarTest runs, I have trouble with giving them any credibility at all just yet. However, I'm betting that if you run the Porsche, it will be a bit ahead of the Nissan, just as in my simulations, but you'll also show the Porsche as being under-rated.
I should do more with CarTest and the 997 Turbo, but again I have not posted results for either nor for the 335i because I admit I have not found the results very satisfactory. I only mention them in passing/off the cuff. More work to be done here. Why can't you be as honest and admit that QJ and your application of it is either good for 2WD or 4WD but not both?

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Originally Posted by bruce.augenstein@comcast. View Post
Finally, there's that whole SAE thing. Almost certainly, the Nissan will show "correct" numbers on the dyno or the SAE will throw them out - and of course if you're correct then the GT-R will be a comparitive pig when our magazine guys give it a run. Won't happen, though. I'd bet quite a bit that the SAE numbers have already been run under current (SAE representative present) rules.
I'm not sure if Nissan has or will use the same official SAE hp standards that GM uses (say for the Z06 at just over 500 hp). Do they currently certify per SAE?

Quote:
Originally Posted by bruce.augenstein@comcast. View Post
Nissan is not only betting at least a couple of decades of legendary performance by past iterations of their baby, they're also betting that the car will be a worldwide legend, or the entire Japanese car industry loses face.
As I undestand the history Nissan Skylines/GT-Rs have a nice long tradition of being under-rated, not a big surprise here!

Quote:
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Nope. The data points we've discussed collectively point to the fact that the jury is still out. Personally, I think the Nissan will be on the up and up, but we'll see.
You sure keep waffling on whether or not there is evidence here. I agree that the jury is out in that we can not say absolutely with no doubt that the car is under-rated. Perhaps the only way to settle that would be by removing the engine and putting it on a very accurate, factory quality engine dyno and that probably is not going to happen. I agreed that my thread title may have been a bit premature or aggressive but no way will I back from the claim that there is evidence and good evidence for an under-rating.
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      12-17-2007, 03:58 AM   #79
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Quote:
Originally Posted by ArtPE View Post
the 997TT never ran a 7:40...

Walter 7:49
7:54 --- 156.456 km/h -- Porsche 997 Turbo, 480 PS/1620 kg (sport auto 06/07) http://www.supercars.net/PitLane?vie...D=2&tID=126501

both on PSC's

there is no way a car weighing 300 lbs more with 15% less torque on street tires can beat those times in the wet by 11 to 15 sec.

as I have shown those dyno numbers can not be true...CAN NOT...
T (lb ft) must equal HP (SAE) at 5250... MUST!!!
yet T=428 and HP = 460...
+1, more evidence. Oh sorry Bruce, that is not evidence either .

However, Art, the 20" Nitrogen filled Bridgestones (depsite being runflats) on the GT-R are probably just ast sticky as PSCs
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      12-17-2007, 06:32 AM   #80
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Originally Posted by swamp2 View Post
Blunt is fine, confused/mistaken is not. If you are still talking about shift times I say BS. You need to get over my appropriate criticism of your past speculation, keep that on that thread and stop tyring to simply turn the tables here. I provided lots of real and accurate actual data along with semi-subjective reviews from journalists about the "feel" of each tranmission, combined with my direct experience with SMG II which pretty much matches what everyone say/knows about that system. I would like a chance to address anything you believe to be speculation (I think I already have done so by the way, but if not, I will keep going).
DSG style boxes work by spooling up to speed the other gear so it's an instant transition between the two gears without any lose in power. How Nissan aren't achieving this is a mystery to me.........don't know about you though as you do seem to have a broad knowledge of most things mechanical.

It's easy to explain why SMG style gearboxes can be felt regardless of the speed of shift that's done but not DSG, sorry I can't understand what is going on that at all.

So if you can explain it in a way that sound logical to me, please feel free.

P.S.

The more I think about it the more I believe Nissan's time between changes sounds about right and what you are feeling is the brief stop in acceleration that you don't get with DSG, admittedly all 0.2s of it.
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      12-17-2007, 09:15 AM   #81
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there is no way a car weighing 300 lbs more with 15% less torque on street tires can beat those times in the wet by 11 to 15 sec.
Now we have your real motive. Despite numerous videos and the close inspection of nearly every motorjournalist in the world, the 7:38 is not to be believed
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      12-17-2007, 09:17 AM   #82
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Try this...

Quote:
Originally Posted by ArtPE View Post
the 997TT never ran a 7:40...

Walter 7:49
7:54 --- 156.456 km/h -- Porsche 997 Turbo, 480 PS/1620 kg (sport auto 06/07) http://www.supercars.net/PitLane?vie...D=2&tID=126501

both on PSC's

there is no way a car weighing 300 lbs more with 15% less torque on street tires can beat those times in the wet by 11 to 15 sec.

as I have shown those dyno numbers can not be true...CAN NOT...
T (lb ft) must equal HP (SAE) at 5250... MUST!!!
yet T=428 and HP = 460...

Try this...

http://wheeltalk.fancal.net/?p=476
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      12-17-2007, 09:18 AM   #83
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In regards to SAE testing, I believe manufacturers are still allowed to underrate, but not overrate.
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      12-17-2007, 01:37 PM   #84
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Quote:
Originally Posted by footie View Post
DSG style boxes work by spooling up to speed the other gear so it's an instant transition between the two gears without any lose in power. How Nissan aren't achieving this is a mystery to me.........don't know about you though as you do seem to have a broad knowledge of most things mechanical.

It's easy to explain why SMG style gearboxes can be felt regardless of the speed of shift that's done but not DSG, sorry I can't understand what is going on that at all.

So if you can explain it in a way that sound logical to me, please feel free.

P.S.

The more I think about it the more I believe Nissan's time between changes sounds about right and what you are feeling is the brief stop in acceleration that you don't get with DSG, admittedly all 0.2s of it.
The "next" gear selected by a DCT/DSG system (whether a upshift or downshift) is not really "spooled up", maybe just a termininology thing but the next gear is fully engaged and is being driven on the shaft that is simply disengaged by the other clutch. The time advantage for the shift comes from three basic reasons, one: no movement of selector forks and dog gears (already done in advance), two: simultaneous clutching operations, rather than clutch in+clutch out, three clutch operations can be very short throw and are hydraulically acutated (result = VERY fast). My strong suspicion is again that the "official" Nissan numbers of .2 s shifts are again an understatement, a typo or a lie. This is the key question. If DCT/DSG boxes get a large part of their performance advantages from their quick shifts how would Nissan ever release this type of transmission that barley shifts faster than a human and is dramatically bested in shift times by the best automatics and by VWs "lowly" version of DSG? The answer is - they wouldn't. If you listen to the N'Ring video of the GT-R the shifts sound very fast and crisp to me but estimating a shift time even by digitizing the audio is probably unfeasible - you must have a highly time resolved acceleration curve to do that (or have a good spec from the manufacturer).

Next more on the subjective side I suspect folks are comparing the GT-R box to the VW/Audi boxes and perhaps if the Nissan box shifts a bit rougher this is the source of those comments. It is not inconceivable that simply managing the much greater power and torque of the GT-R required shifts not quite as smooth as the VWs/Audis. Lastly there is the issue of software. As I have mentioned before the software component of a DSG/DCT is a critical part of the entire system. The entire nature of the shifts, their feel, the speeds and to some extent their smoothness and the quality of the downshift throttle blips will all be able to be tailored to some extent with software. We are talking about rates, ramping profiles, sequencing and next gear guessing all happening in millisecond resolution. To deny the importance of software for such systems is absurd.

P.S. My favorite page that explains the mechanicals of all sorts of transmissions is here. It is really worth a look and read. Excellent web page.
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      12-17-2007, 01:53 PM   #85
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Now we have your real motive. Despite numerous videos and the close inspection of nearly every motorjournalist in the world, the 7:38 is not to be believed
Come on now... no one is denying the sheer reality of the video and time we all saw. However, there is a great deal of critical factors that will only be examined by those that really dig into the event and desire to fully understand it. The key questions IMO are these:
  • How much of an ace was the driver compared to Horst and the more standardized times we have for him from Sportauto? How much of the time is directly attibutable to the driver?
  • How sticky are those darn 20" Nitrogen filled Bridgestone run-flats, PS like, PSC like or PSC+ like (or other comparisons)? Once we know this we may be abel to say how much time the tires account for compared to another tire.
  • How much time did the DC transmission save over a MT?
  • Is the car under-rated and what effect did this have on the lap time?
  • Has the car simply totally re-invented traction, AWD, chassis dynamics/suspension and stability? Now any idiot can break 8 mins on the N'Ring in the car!

5-10 seconds for each of these effects really adds up to a huge difference (25-50 seconds!). Furthermore since at least 3 of these factors are involved for sure, this makes the time simply much less special.

A lot of folks are thinking along these lines. I am ignorant of points 1-3, 4 is "impossible" and the car is truly magical per point 5. This reasoning is seriously flawed, I don't see how anyone who knows anything about fast cars and lap times can argue along these lines.
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      12-17-2007, 02:14 PM   #86
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It is not inconceivable that simply managing the much greater power and torque of the GT-R required shifts not quite as smooth as the VWs/Audis. Lastly there is the issue of software. As I have mentioned before the software component of a DSG/DCT is a critical part of the entire system. The entire nature of the shifts, their feel, the speeds and to some extent their smoothness and the quality of the downshift throttle blips will all be able to be tailored to some extent with software. We are talking about rates, ramping profiles, sequencing and next gear guessing all happening in millisecond resolution. To deny the importance of software for such systems is absurd.

I did think about the power difference between VAG DSG motors and this GTR but then remembered that the Veyron is basically using the same gearbox and it's got twice the power and torque of the GTR and yet it's shift is totally smooth, just like the same as in any other VAG with DSG.

I might be down to the extra shafts involved in their awd system that aren't there in either VAG product.

Frankly we could discuss this till the cows come home and still won't know the reason.
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      12-17-2007, 03:02 PM   #87
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A lot of folks are thinking along these lines. I am ignorant of points 1-3, 4 is "impossible" and the car is truly magical per point 5. This reasoning is seriously flawed, I don't see how anyone who knows anything about fast cars and lap times can argue along these lines.
Who is saying the car is magical?

Yes, a combination of all those things and more are making the time possible, that is obvious on the face of it. Nothing about any of those factors makes this car less special. Is a Veyron less special because we can understand how slick aerodynamics and 1000+ bhp can make a 250+ mph capable car?
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      12-17-2007, 04:22 PM   #88
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Who is saying the car is magical?

Yes, a combination of all those things and more are making the time possible, that is obvious on the face of it. Nothing about any of those factors makes this car less special. Is a Veyron less special because we can understand how slick aerodynamics and 1000+ bhp can make a 250+ mph capable car?
Some folks here had that attitude, although they would not cut to the chase and use the word "magical". Many all over various forums on the web had this attitude as well. I tend to disagree though about what does and does not make the car special. If all of the other very well known factors are what gave the car it's time then again the time is less special. What is the most special IMO about the car is simply it's performance to price ratio and from what I have read how easy it is to drive very fast.

Last edited by swamp2; 12-17-2007 at 04:44 PM.
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