MT: GTR makes 507 hp... at least! / Edmunds: GTR Road Trip / TG: EvoX vs GTR
 

1. MOTOR TREND: 2009 Nissan GT-R Makes 507 Horsepower... at least!

http://images.motortrend.com/roadtes...-R+on_dyno.jpg

http://images.motortrend.com/roadtes...dyno_graph.jpg
Link: http://www.motortrend.com/roadtests/coupes/112_0803_2009_nissan_gt_r_dyno_test

Well, as expected... :twisted:



2. Edmunds Inside Line: Nissan GTR Road Trip

http://blogs.edmunds.com/.eea5148/cm...osure..eea5149
Link: http://blogs.edmunds.com/Straightlin...anGT-RRoadTrip (note it's a blog, so you should read it from the bottom of the page and then click "previous page" for the next (newer) page)



3. Top Gear: Talkin' about an Evolution - EvoX vs GTR (by Matt Master)

http://www.topgear.com/content/featu...es/4/large.jpg

Link: http://www.topgear.com/content/featu...ries/12/1.html


Enjoy reading guys! (if you're somehow interested in this GTR-related stuff of course :P)

Thanks mate :thumbup:

How did I know that this would be your topic, Toffy :-P
I give you points for obviously being a passionate GT-R fan, but being cool about it and not a fanboy.

I'm not suprised at the comment that the car produces 507 hp - upto 570 hp at the crank! Something had to explain the concesus of astonishment at this cars performance!! :-)

Actually this dyno raises even more questions. 430 doesnt seem to indicate 570 unless theres something really wrong.

Why does it raise more questions? A Z06 pulls on a dyno.. you guessed it.. more then 430. In fact 450 bhp.
http://www.z06vette.com/forums/f70/0...7lb-tq-110018/
First dyno was :
452.17whp/421.16 lb-tq
Second dyno was 456.72whp/427.22 lb-tq
Last dyno was 437.27whp/402.55lb-tq
(Just one example of about 100 easily found through google or by talking to a corvette guy.


A base C6 pulls 390 bhp. Now granted awd loses more through the driveline, but this would prove the z06 has more bhp and is lighter.

Nothing is wrong at all. The C5/C6 drive train is well docmented and well known to have a loss of approx 18%.

The AWD system with its various bits and pieces WILL consume more power along the way - there is nothing left to debate about C5/C6 drivetrain loss.

I think you missed my point. Half the magazines have concluded that the Nissan is way faster then the Z06 (in the 1/4). Here we have a dyno resulting in a rwhp way below what a vette has. Now granted numbers always vary greatly dyno to dyno, but I think we can safely say the RWHP of the GTR is not significantly higher then the Z06. Yet it weights some 700 lbs more. That is the part that makes no sense.

The drive train loss makes perfect sense- well within limits at least. Id say 570 bhp doesn't make much sense but the rest of the numbers do. Its the comparative dyno that raises the WTF flag.

Not at all.

Remember, the drive train loss measured, is on a static dyno. It is possible that during operational conditions, the complex nature of the GT-R drivetrain might mean the drivetrain loss varies between some maximum and some minimum amount as the active components take charge.

Unlike a static mechanical system that the GM produc has, where the "lockup" condition of the drivetrain components on the dyno is the same as on the road.

So on the dyno, only 440hp of the available 500++++ HP gets through, but at other times perhaps more of those crank HP get through to the ground.

And then when they do get there, the ultra sticky tyres are able to make use of them instantly.

There is no doubt that technical wizardy and sticky tyres allow the beached whale to be faster than we think it should be - and I think the finl proof will be in the pudding when tyres begin to go off and of some heat soak limits the available power - we will start to see the GT-R behave the way we would expect.

Oh, thank you, sir! :)


Just finished reading Edmunds blog, hell they decided to buy one! LOL
Looks like they really enjoyed playing with that 3800 lbs toy!

Not to argue too much here, but the nissan doesnt actively bias torque laterally. Their diff essentially acts the same as gms. While we could expect some increase in bhp off a dyno from both cars actually, your talking drastic swings here. This would not (with some exceptions) be indicative of say car and drivers acceleration times.

As for tires, yes they drastically help. Though take a look at the times from road and track again and you see the car roasted once it passes a certain mph. Then we have a test by c and d where it goes light years faster. Theres no arguement the nissan has more grip off the line. The questions come in from the z06 having higher terminal velocity at the end of straights in c and ds test, the dynos showing the z06 having greater bhp, and the z06 being equal in all but a skid pad test. Is it possible for the z06 to still be significantly slower given these static tests? Yes. Is it likely? Hells no.

Edit: Straight line discussion only here folks.

Yeah - I used the term "lockup" in the context of the entire drivetarin systme allowing power to be routed away from the psinning tyres, not specificaly laterally in the LSD components. I was struggling to find a term for what I was trying to explain hehe ;)

Essentially, I wonder if on the road under load, the GT-R might not let more power though to the ground at certain times, compaired to other times, and tht you cannot simulate this on the dyno perhaps.

Just an idea.

Anyway, in this context an engne dyno is needed hehe. Maybe Edmunds will allow the enging to ripped out of their white car and be engine dynoed ;)

It's possible but raises the question why dont we see the same on the 911? AWD certainly aids off the line, Id expect the z06 to lose 0-60. That being said I've seen very little historical evidence that shows gains where grip is not an issue (say 2nd gear and up).

Note: Again still in a straight line only discussion here folks.

:-D:-D

I think the key here is this is not a straight up awd system we're talking about here. It favors the back until the back needs help much like the r8 this allows it to as rc said maximize it's power at different times off a dyno where on a dyno it might not know what to do. This is an amazingly engineered piece of technology designed to tear up the road and track not a dyno.

Did I stutter when I said it doesnt have active torque biasing? The system in the car is no more or less advanced then the 911. And your not going to see that much real world diff dyno to track in terms of bhp. The simple reality is, shifting the power through the system does not historically make enough of a difference to justify the difference in performance to dyno.
Also the road and track times had a mph quarter trap speed of 117-118 mph.. Lower then the z06, and what we would expect given this dyno.

So when they said on 5th gear that normally 100% of the power is at the rear, but at moments it gets shifted around to all four, that was misinformation?

I don't think you understand. We aren't talking about the ability to adjust bias based on slipage, which is what the nissan currently has. It does not have the ability to adjust based on gs and other inputs. The same system is in the 911 and its not some huge leap. Which brings us back to my point re: historical inference does not backup the assumption that a huge jump in bhp will occur.

Essentially what your trying to argue is that when going from a 95 percent lockup to a 50/50 lockup your getting more driveline loss. While true, its not historically true that it would be as high as your thinking. While coupling the rollers would eliminate this issue entirely, even seperate your not going to lose massive amounts of power.

Heres a good writeup to what im refering too:
http://www.nissanforums.com/nissan-g...a-ets-pro.html

Speaking of which, the whole 25 percent driveline loss bit is a bit of a farce anyway. Take a 1000 bhp car. Theres no way in hell it could lose 250 through the driveline. The losses go to heat. Could you imagine how hot the axles and transmission would be? RC mentioned a number for the z06. Im not even sure I buy it honestly. If we go purely on the sae certified number of 505 bhp and an observed dyno of 450-460 by most owners, that nets out to a 10 percent drive train loss. It would make sense that a 505 bhp skyline, assuming a 5 percent variance in output from the stated 480 bhp which happens alot actually, would have 430 bhp due to the inherint extra friction as part of a two axle system. The difference in this two axle system, if information from the 911, lambo, et all bear as examples, would actually come close to reflecting a 430 bhp output. Under that situation switching to rear bias should only get you back up to the z06s rwhp. It should not allow a trip beyond significant enough to overcome driving around rosie odonnel and two of her fat friends in the trunk (aka the gtr). Which again proves the point the car does not have significantly more power then the z06, despite significantly more weight. Which begs the question, how are cd seeing the acceleration they claim? And why is road and track hushing up the slower traps they saw?

I guess I've done a poor job making a point here, but on the dyno shouldn't it be basically a rwd car and not speculated on as a awd car. Therefore wouldn't the idea that it has 570hp be a improbability.
But the comp systems would then give better acceleration times then a rwd car with similar horsepower due to better use of that power.

A dyno simply measures the force exerted by the wheels over a given time interval. With that, horsepower is calculated (force x distance / time . . . power). Being awd, the GTR will lose a higher percentage of power through the drivetrain than a rwd car would.

In a straight line it only would in terms of grip off the line. Unless one set of tires are spinning there is no gain by applying torque to the other set of wheels. Hence the GTR should beat the z06 off the line, but should be roasted anywhere else (again see the r and t times).

This is true, but the point is the switch between the two will not generate a huge increase in bhp when the car switches modes. If you assume the rear portion of the awd system has a drivetrain loss similar to the rwd that means the awd portion should at least in theory lead to increase much less then half the drivetrain loss of the rwd. Why? Because you don't factor in the transmission loss twice.

If we assume a bhp of the gtr of 507 bhp, thats 2 bhp more then the vette. Now unless some miracle occur we can also assume similar driveline losses. So we can essentially estimate the bhp in rwd mode is probably close to that of the z06. We can also pretty assuredly say its not going to result in bhp well beyond that. Which again begs the question of how to move 700 extra pounds.
This basic discussion, granted with the assumptions being assumptions, applies to all manner of other awd cars. Cars like the 911 and lambo have not seen a miraculous jump between the various modes. You would expect similar experiences since the systems are relatively similar (other then the gay ass double driveshaft).

It has been quite accurately determined over many many many thousandsof dynos that the C5/C6 drivetrain has an approx. 12% power loss when measured on DynoJet rolling road dynos.

385bhp = ~335rwhp
405bhp = ~355rwhp
436bhp = ~390rwhp
505bhp = ~450rwhp

The %age may be slightly reduced as the crank HP increases - but on a 1000bhp setup, there is close to a 120hp power loss to the wheels.

I would not be surprised that in the end, once someone takes the GT-R motor to an engine dyno, theyw will find that there is closer to a 20% or higher drive train loss on a static dyno setup, but that by conventional calculaiton this loss is less and also variable under load on the road.

:)

Ok, new day new attempt to get my point across. The GTR is under normal conditions a rwd car that uses power to the front wheels in trouble situations. So unless it was slipping on the dyno there was no awd drivetrain loss meaning the idea of 570hp is not practical.
As for the power distribution system I agree the gains are only going to coming during slippy periods like launch and that the z06 should run it down fairly quickly thereafter, but I don't doubt it beats it to 60 as through this new system not only does it have that extra grip of awd when it needs it, but it has it without the awd bog theoretically.
I've said it before and I'll say it again the gtr is an off the line/time attack performer that is too heavy to do well in the long run, but this whole conspiracy theory about an extra 100 horsepower is a witch hunt. Technology has moved forward you can't just look at power/weight ratios when talking about this new super computer of a car.

^^ Nice post Madpony.

Madpony, you are assuming that on the dyno, the front wheels aren't exerting force on the dyno, and that isn't the case ;)

I'm going off that assumption based off the fact that from what I've heard they wouldn't be.

edit:
Ok, just looked it up and found out apparently the least it'll put the front is 2% so yes there would be some awd drivetrain loss. I blame Plato's slight overstatement on 5th gear for the mix up.

All right gentlemen, here's something to ease your discussion there (Dyno vs Road power graphs included) :D


MOTOR TREND: 2009 Nissan GTR Acceleration Test

http://www.motortrend.com/roadtests/...est/index.html

Results:

0-60: 3.2 sec
0-100: 8 sec
Quarter mile: 11.6 sec @ 120.0 mph


http://images.motortrend.com/roadtes...ison_chart.jpg

http://images.motortrend.com/roadtes...ison_chart.jpg

Maybe the Bugatti would be a contender for the GT-R. Maybe.

Thats 11 percent drive line loss.
I highly doubt it. That would be nearly double the corvette. I cant believe that the transmission portion is 2 percent. 20 percent drive train loss would be greater then 100 bhp drive line loss. Thats alot of heat and I don't buy it.
It appears that last test posted proves my point. Also slower then the z06.

Last I checked the best stock time for a Z06 was a 10.9.. and even mag reported times were faster then this report. Motor trends own times for the z06 were "the standing quarter in 11.5 seconds at 127.1 mph". Significantly higher then that of the GTR. These are results I expect.

Great stuff toffy.

In considering this thread I realized things need to be put into perspective on the GTRs acceleration difference to the Z06.

The Corvette Z51, a great car, my personal car, and 30k less then its bigger brother the z06 (unless you count the discounted z06s - get one for 62k new I saw today) runs a 1/4 of 12.1 at 117-119 mph. Why is this important? Without the launch control the GTR ran a 12.2. Losing to the z51. They state themselves that engaging launch control is difficult. Lets however assume they made it into this mode. The GTR then ran a 11.7 at 116 mph (120 if you ask edmunds and rt, but you get the point). What does this mean? It means the Corvette Z51, a 45k msrp car, is significantly faster then the gtr in the upper mph. In fact it indicates with the right driver/tires/launch the z51 would probably be kneck and kneck with the GTR. That should put the GTR in perspective re the Z06.

IMO, acceleration performance of Z06 and GTR shouldn't be measured by 1/4 times as these two cars are very different.

Generally:
0-100 mph: GTR>Z06 (AWD, short gearing, better tires and seamless shifting from DSG overcompensate for the lesser P.W.R & T.W.R);
>100 mph: Z06>>GTR (greater P.W.R & T.W.R becomes critical)
Rolling start (generally): Z06>GTR

And what's all the fascination about straigtline perfomance anyway? I personally don't care if one car does 1/4 faster than another (you can perform approximate calculation and tell that without the actual run anyway). Race track - that's where you learn the true worth of the sportscar! :P

Even Motortrend thinks the Z06 is slow these days

http://blogs.motortrend.com/6238202/...low/index.html

April Fools!!

Just read it! Hahahahahahahahha! LOL

Until someone pulsl the GT-R motor out and puts in on an engine dyno, the %age drivetrain loss is simply a guess by all parties.

Once this has been done, people will see the drivetrain loss of Nissans AWD system is more than the approx. 12% loss on a DynoJet dyno for the C5/C6 drivetrain.

The best write up of a vette I've ever read.

I agree that the loss has to be more than 12%...there is no way its under 15%.

I have a hard time believing the GTR produces 530hp. If it were that much, the 997 TT would never be able to keep up. I know Nissan didnt freak up the gearing on the low gears that bad.

Did you look at the graph from motor trend on the previous page. Anything above between 70 and 80 is the z06. Why is it important? Well first because if the vette is ahead by 70 mph, then that means it accelerated faster long before that point to catch up from its 0-60 deficite. Also probably because along with the track articles it proves the koolade is a bit tainted. No one has done a legitamate (read not driven by a nissan driver or a track with a top speed lower then an auto cross course) track comparison.

No one has argued with you re: greater. What Im pointing out is that the 11 percent of the z06 is 450 rwhp to 505. If the nissan is 430 rwhp, as these tests indicate (oh and tests on a coupled dyno gave at best 450 rwhp as we would expect, which would be road conditions) then 505 engine hp to 430 rwhp would be higher then 11 percent, and actually it would be what we would expect. 15 percent drive train loss is perfectly reasonable. Any more then that that rear better have its own cooling system.

MOTOR TREND 2009 Nissan GTR Handling Test: Godzilla turns and stops as eagerly as he charges.

http://www.motortrend.com/roadtests/..._handling_test

http://images.motortrend.com/roadtes...+side_view.jpg

Done with Bridgestone Potenza RE070R RFTs.
Hmm, that's pretty damn good considering its weight.

Yes, it performs well and will eat through tires nicely.

Car and Driver, the magazine that tested the GTR running to 60 in 3.3 seconds, also agrees that the car's horsepower rating is probably an underestimate. See the letters to the editor section of this month's issue.

The car's trap speed at the end of the quarter mile says alot about how much work it has physically done and therefore it says a lot about the power as well. Here's a link to one of those ball park figure quarter mile calculators. Such calculators are far from perfect and don't take many variables into account but they do a fairly decent job regardless.

http://www.tunercalcs.com/hp-from-qu...rap-speed.html

The reason the straightline performance of the GTR is ever so fascinating is because it's obvious that the advertised power figure is wrong no matter how much traction magic and "more efficient horsepower distrubution" the computer dishes out.

Z06 vs GTR on the streets:

http://www.autoblog.com/photos/first...n-gt-r/734036/
http://forums.corvetteforum.com/show...post1564834849

The first story of the Vette driver is pretty alright, but the second one kinda make me feel like he's a jerk.