^^^Hence why is it not slower than the ZR-1 on that last long straight stretch on the Nord? ZR-1 is lighter, more powerful, and geared better...........yet the GT-R is faster...........buckets of awesomeness my friend, that's what the lizard has........
............How much power is lost in the journey to the road is not accurately known, but a 15-percent loss for rear-drive cars with manual transmissions and a near 20-percent loss for four-wheel-drive cars are good estimates.
On MotorCity Speed’s Mustang dyno in Commerce Township, Michigan, GT-R No. 4 produced a peak of 415 horsepower at the wheels. Based on our 20-percent loss estimate, the engine output was 519, or 39 horsepower more than Nissan’s stated 480.
C&D uses an assumed drivetrain loss. Again the GT-R is the first of it's kind running a rear double clutch transmission. Looking at every dyno in the world you don't see a drop in torque when running the car. This means no dump on the blowoff which means no loss of boost. This is one of the reasons why the GT-R performs so well.
The ZR-1 has the advantage through 60 with respect that it can run the entire time in 1st gear. The trouble with cars like the ZR-1 and Viper is they have a hard time getting all of that torque/power to the road without vaporizing their tires.
Well, if it's 480 as claimed, the power lost to heat and friction in the drivetrain amounts to just 10.3 percent. "No way," says K&N's James Yim, who reckons the bare minimum lost to all the friction and gears in this rear-transaxle all-wheel-drive twin-clutch manual (a radiator about the size of an intercooler is dedicated to cooling the transaxle) is 15 percent. He'd bet it's more like 20 or 25 percent -- especially considering that during such a dyno pull, the ATESSA ET-S AWD system has to route nearly 50 percent of the torque to the front axle to spin that huge front roller on its own (which it won't do during a dry-road acceleration run). Consider too that, although these figures are all weather corrected to SAE standard conditions, the conversion doesn't take into account the loss of intercooler efficiency in 93-degree weather. Given those three drivetrain-loss guesstimates, here's how the crank output looks:
I would liked to have seen what the torque split was for the dyno runs. It's easy enough to find out if the dyno operator just ran some video on the interior of the car.
I will tell you for a fact that yes when getting off the line there is most definitely a near 50/50 split from the front to rear wheels. This split also diminshes very quickly. People would be surprised how little of the time the GT-R spends with a 50/50 or large torque split to the front axle.
I will again repeat that there are dynos that can measure the angular rotation of the drums and using their rotational inertia, along with the rotational intertia of the wheels, measure the actual parasitic loss for the powertrain components. This measurement backed up Nissan's claims.
A lot of people did not and still do not believe that result.
The one way to settle this (and what none of the speculators wants to do) is pull the engine and stick the VR38DETT on an engine dyno this will tell you what the engine is putting out versus what's getting to the wheels.
..........again the drive train losses are estimated not fact.
OK...........I realize a serious flaw in my thinking. 14% will not believe me. I will look at this a different way.
Since 14% loves the quoted drivetrain losses, let's look at the standard 15% that people use for the rear drive ZR-1.
638 hp with a 15% drivetrain loss gives us 542 rwhp.........pretty much in line with what owners have reported for their ZR-1's.
C&D says they dynoed at 415 & 420 whp. MT was 410 to 435 whp.
So the ZR-1 is 3,300lbs/542rwhp = 6.09 lbs/hp
The GT-R is 3,800lbs/432whp (using Nissan's claimed 10% drivetrain loss and 3 hp shy of the highest hp measured by MT) = 8.80 lbs/whp
Funny, why does the power to the wheels favor the car with the Bowtie, yet the GT-R make such a good showing? To match the ZR-1 the GT-R should be making 624 whp at the ZR-1's 6.09 lbs/hp, yet that is not the case and that is off of C&D and MT's measured whp figures.
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