482 ps (475 hp) and 59.2 kg/m (428 ft-lbs) at the hubs.





Results will be printed in the 12/25 issue of Bestcar. Also said that the limiter came on in 4th gear so there should be more potential.

Thanks to Zakira for the translation.

http://minkara.carview.co.jp/userid/149571/blog/c227132/

Nice, so a customer already took his new GTR into Super Autobacs for confirmation on the stated numbers.

To the wheels, or the crank?

Neither exactly, but should be very close to at the wheels

What the heck is at the hubs??? I guess I am not a dyno guru, so im not sure what that means.

Unless the power is measured near the wheels after all of the rotating power-reducing elements such as driveshafts and AWD trickery and what not, then you might as well say that is at the crank.

Surprised at the torque curve.

Its nothing like the flat curve between 3200 and 5200RPM from Nissan.

I know the dyno is dynamic but the lack of torque at 3200 RPM is not good.

Paul

Look at the pictures. Hubs are what wheels mount on. Ever change a wheel? Did you bolt the wheel to the crankshaft?

So yes, it is after the entire drivetrain, the only thing piece missing is the loss between tire/wheel and dyno rollers on a typical dyno.

well thats nice to see. the new gt-r is well under rated. thats somewhere around 530-550bhp depending on drivetrain loss. dynopacks read a little on the low side. cant wait to see it on a dynojet. well that explains the power to weight ratio that everyone has be arguing back and forth. im so anxious to get one, this car will make over 700bhp with both ons

Well you aint gotta be a smart @ss about it. I didnt say "what is a hub". But like I said I am not a dyno guru so I not sure how they are measuring. At the wheels is measured through the wheels on the roller.....well the hubs arent rolling on anything so what the heck is it measuring...maybe it has some type of light senor or magnetic sensor that measures rotataion cycles of the hub. Anyway, explain how it goes then o-might-one.

From their website.


http://www.dynapack.com/dynapack.html

The Dynapack uses hydraulic brakes just like an engine dyno that measures from the crank. They are attached directly to the hubs in place of the wheels. Dynapack says this eliminates the tire slippage that can occur with inertial (drum) type dynos. It is measuring the power to the hubs of the car so it includes any drive train loss but does not include tire slippage if any. All we need now is the drive train efficiency and we can calculate the horsepower. 480 is not the horsepower number. It is higher. And the torque is understated. I don’t remember Nissan saying the torque curve was flat but that there was X amount of torque available between 3200 and 5200RPM but even the torque measured is low at 3200RPM. It does flatten out at 4500 though. The trace drops dramatically at 6200 so this is probably the limiter kicking in and robbing the power. I would like to see a complete run to know what the real numbers are.

Well this guy feels it would be 554 hp, if measured on rollers:

http://minkara.carview.co.jp/userid/241145/blog/7134633/

He's using a factor of 1.15, which seemed to be the case with an Impreza they ran.


A bit of correction in my original translation. This dyno run will be covered on the GT-R issue of Bestcar magazine, available 12/25.

Really that 475 seems a bit high to be at the wheels. AWD systems usually have >20 (sometimes >25%) drivetrain loss. That would put the crank power at 570+......which sounds good for the ring time/weight argument but it doesnt add up for a top speed of less than 200mph for a car with a .27 cd.

I would like to see different run on a wheel/roller dyno.

Nissan has already given us the GT-R's drivetrain loss value, and it's 15%. calculating from there, it indeed is around somewhere around 530-550 ponies at crank.

Where did you see that drivetrain loss figure?

Pretty much confirms what I've been saying all along. The GT-R is WELL underrated in power...at least the JDM is anyway.

Wait!! I looked closely at the pics and the screen says flywheel so it is alredy doing a conversion calculation.

Pretty much what everyone's been saying. It doesn't take much upstairs to deduce that...

If the loss is 15% then that number is believable..........but 15% is VERY low. The GTR has more AWD components than any other AWD car....so that would equate to even more losses.

Scratch that. I called DynapacK and was told that the machine has the ability to convert but in the picture you look at the "TCF" box and that tells you what is the conversion calculation being used. In the pics it says "1.00" so that is what the cars made at the wheels. Sorry for the last post.

would be nice to have seen what another car put down as a comparison. one single dyno number is not all that useful..

im surprized to see a drivetrain loss of only 15%. my fd rx-7 has about 15% drivetrain loss, this has been proven over a good amount of stock car dynos. then again my car is a 1993 and this is a 2009 with a bunch of technology into it. so i am sure they cut the drivetrain loss down. maybe the tranny in the rear of the car helps with the awd drive train loss.

edit. also forgot to mention the gt-r puts 98% of the power to the rear wheels when no wheel spin is detected. that helps a ton in drivetrain loss.

1. Very encouraging numbers! Though I can't say I'm surprised if this car's power is underrated.

2. On Drivetrain loss... you can't use the figures from other awd systems. This an entirely new configuration and Nissan has made a point of saying how the drive shafts, diff, and motor were designed to minimize that loss. If standard awd system loss is 20%, I'm willing to bet the GT-R's is a few percent less than that.

3. If this is true, then it seems Nissan has really to do nothing to sell it in the US at 480hp rating instead of 473hp rating.

the 15% loss Nissan stated was Gross VS Net HP not Crank Vs wheels

No matter how Nissan says they have designed the parts to minimize loss, they have actually included more parts to induce losses in the system...therefore it probably equates to about the same.


15% seems a bit low.

dynapack usually reads higher than other dyno's, as much as 5-6%

it would be interesting to see it on a load based dyno to see if the boost loads up a little better and the curves look better, those curves don't look great kind of peaky

The GTR is quite amazing, I'm surprised at the amount of air the stock twins can push @ 10.5PSI.

482ps = 476bhp

This seems very promising. I need to drive it (or at least a car w/ a similar tranny) and see how it compares to a six speed. I new since those times came out and due to the fact all the other GTR's were under-rated that this car was under-rated. I'm seeing 600+ BPU potential which will blow the Supra out of the water, and still have traction.

basically we still don't know much. the actual # is not really significant until we have another dyno run from a typical/stock car to compare this one against.

someone correct me if im mistaken:

GROSS HP is the actual engine by it self with nothing attached to it. NET is the engine in the car.

Here is an article I found on the web. It is what I believed the differences to be also

GROSS POWER
Before 1972, most American automakers rated their engines in gross hp, under Society of Automotive Engineers (SAE) standards. Gross hp was measured using a test engine running on a stand without pumps, extra fans or anything else installed. It is the maximum theoretical value of power, and nowhere near what a car gets on the road. Gross hp figures were so often manipulated by car manufacturers and marketers that the SAE decided to adopt a new standard of power that took accessories into account.
NET POWER
The SAE chose to use net hp ratings, which measures engine power at the flywheel, but still not counting drivetrain losses. It does take into account all accessories, intake and exhaust systems. By 1972, most carmakers quoted power exclusively in net hp. Net ratings are more accurate than higher gross ratings. Many people incorrectly report net hp as being measured at the drive wheels. They confuse net hp with wheel hp, which is even lower. Wheel hp is what you get when power at the drive wheels is measured using a dyno. The worldwide standard remains net hp however (whether under American SAE, European ECE, German DIN or Japanese JIS rules). The same story applies to all torque ratings too.

another dyno thread?

the dyno results were calculated using a dyno JET. there are 2 main types of dyno's. they each have differnt results, and each run is differnt based on many variables (like weather, elevation, etc).


what did nissan do to calculate there 473hp? did they use a crank dyno (manufacture uses), a dyno jet (shown in the pictures here), or the other main type of dyno?

why is everyone like WOW? this is what nissan said the car is rated at. its not over rated or under rated. of course the ECU is the limiting factor. nissan knows this and i belive the engine can handle more without much issues, the only thing stopping it is the ECU, which can be piggy backed with annother one, mines already deciding to do that.

in any case there was information that many differnt ECU's will be distributed to many differnt regions and that future gt-r's will have better ECU's for obvious reasons, and nissan is going to use the same engine for years to come.

sofar i read that everyone thinks the vr38 produces more hp(at the crank obviously), but due to the weight its much lower. who cares. thats just the freking car, you dont drive the engine.

This dyno is measuring the HP at the hubs. If these numbers prove accurate then the engine is making approx. 550 hp.

On my S2000 the Dynapack measured 10-15hp higher than a dynojet when my S2000 was putting down 345.

exactly, plus many variables like correction for temperature and humidity.... Dyno numbers are just too tough to use for an exact measurement like they would use on an engine dyno. basically it is a car with some power, and with some breathing mods like cats and intake will probably have some nice gains and in addition to ecu tuning and tweak the boost up a hair you will have a beast.

that being said, I am not sure that if I get one I would do any such mods to it, I am not looking at this car for power but as an overall car, I have the power with the 350Z.

My understanding from personal experience is that this type of dyno is a bit more accurate than the ones you just drive-up onto. There is a little bit of difference in the power each will determine though, and that is due to the absence of rotating mass (wheels). They are both determining the HP at the "wheels" though, so this includes the drive-train loss. This is going to be less than what the engine puts out at the flywheel (obviously). So...if this dyno is saying the GT-R is putting down 482 hp to the wheels, then (shooting on the low side with 10% drive-train loss) we are looking at about 530 bhp (brake horsepower). If we up the drive-train loss to 15%, then we're looking at 554 bhp. 20% = 578 bhp.

Doing the 20% figure leads me to believe that there isn't very much drive-train loss. 578 bhp would be exceptional, but not likely. I think we're going to be in the neighborhood of 15%...putting the bhp @ ~550 bhp. This is what would make everything add-up with the ring times, 0-60 and 1/4 times.

Yes

Before we get to excited though we need to wait for another dyno to be performed to verify these numbers.

Nissan used the term “net horsepower” which is at the crank with all ancillaries (power steering, AC and the accessories) connected not the power to the wheels. The Dynapack connects to the hubs and is closer to wheel HP than flywheel/crank HP. Wheel HP and Net HP are NOT the same. Net HP does not account for driveline loss as WHP does.

well.. if thats the case you can free up horse power by making the car lighter. the lighter it gets the more horse power gets free.

same with the restrictions ie intake and exuast - that will remove the cat's and free up some weight - specialy a titanium exaust would be nice!

but overall, your not adding any horse power... your freeing it up. and yes the dyno jet and strait dyno are differnt and not real figures. you cant get a real figure of horse power unless your driving it on the road with monitoring software/hardware. but that wont give you crank hp.

sofar has any tuners talked about differnt turbos?

In a different thread I ran the numbers and came up with 550BHP also. The performance claims all pointed to 469WHP (according to my calculations) and using 15% driveline loss, I came up with 550BHP to do the things that Nissan claimed. Didn’t Nissan always underrate the power of the GTR cars?

Well I've said this several times. Nissan must've had to underrate the HP to get the car by the Ministry of Transportation, which is very conservative and frowns upon any domestic car with high HP (although I was wrong about overrating the weight).

That is why they have that speed limiter that "can't be" cut off, and the ECU that is "unhackable." They made the car so untunable because of this, to appease the government. That was their agreement with the Ministry to have the car approved for sale in Japan.

I think Nissan was playing possum which they could do before the car was released. Now that it is out and other people have the ability to test it, more facts will come to light. Industrial counter-espionage. Look at what it did to Porsche. They figured a 20HP bump would be enough to put the back out front but we will see if that is enough to do the job or they will have to go back and get more power to state a higher number. Since the stated number carries a lot of marketing clout. You know, I have more HP than you do. Mine’s is bigger than yours.

Also don't forget that the limiter kicked in. It most likely would've dynoed higher if not for that.

Yeah. Didn’t Nissan state that the peak HP was at 6400RPM? The trace on that dyno run stopped at like 62-6300.

We need more of these personal dynos before accepting this as fact (550bhp). It's easily believable, but more proof would be nice.

Also, that Nissan vid on the engine dyno could've had numbers plugged-in to estimate WHP instead of bhp. It's easy to manipulate figures however you'd like.

i just noticed this thread is linked on a bunch of car news websites

Its not uncommon for companys to under rate their engines. In fact as of late it seems like the new trend (Z06/Viper/335i/etc.). Nissan wanted the nice 480HP(US)/480PS(JP) ratings to match the Porsches. But under rating it would be to their advantage as it would make the GTR look like a better built car performing better with the same power. This is only one dyno so we can't set anything in stone, but it is a very good indication of the actual power output on this car. It is with out a doubt making more then the claimed 480HP.