Nissan: Base Model Gt-r Does 7:29 At Nurburgring

[Basti]

geez, I wonder what the cordia trbo does it in

GOLD!

[GTS4-32]

thats a terrific effort, cant believe it, i was bragging to guys about the 7:38... The v-spec is gonna be wicked!

[Howie]

geez, I wonder what the cordia trbo does it in

bwhah... i was just gonna say ask roger, but then madgt4 beat me to it

[thrtytwo]

PINGPINGPINGPINGs ~!!!

lol how can you question an official statement from nissan ? fair enough its not gospel but they have a lot to lose from lying lol. I'm sure they wouldnt want to give anybody anything to say bad about the GTR by lying

[Phoenix AZ]

I dunno, I'll cop a lot of flack over this but 7:29 sounds a little too fast to be realistic. Remember the R33 breaking the 8 minute mark and then no one else being able to match the time? I just can't see the the R35 doing the 'ring that fast.

***PUTS ON FLAME SHIELD***

From what I understand the track conditions were improved compared to the 7'38" run the last time they were testing at the track.

Apparently, Mizuno is also engaged in continuous quality improvement on this car, re: performance attributes. This is definitely a good thing.

All further JDM and all US spec GT-Rs are getting different motor mounts with different bushings; I expect polyurethane leading to the 'claim' of harder engine mounts. There is also a harder transaxle bushing. The statement reads that these "small tweaks ...... stop the mechancial parts from moving under extreme cornering. It's detail like this that enabled the new 7 min 29sec... (Mizuno)". Also: "The new mounts make the car feel more together in extreme circumstances,' he said. 'We've also changed the spring rates front and rear – it's a minute change, they're just 0.1kg/sq mm stiffer. But it means the movement of the suspension and powertrain are more perfectly tuned."

So it looks like they have made some small adjustments to handling characteristics; and they don't look very expensive either. I am sure the original JDMs can probably be retrofitted / adjsuted with these pieces pretty easily.

[Phoenix AZ]

thats a terrific effort, cant believe it, i was bragging to guys about the 7:38... The v-spec is gonna be wicked!

There probably will be a few bling pieces associated with Spec V, but...

The weight reduction is primarily through greater use of carbon fiber panels and light-weight race seats. These can likely be purchased after-market from Nissan or other. If people are going to autocross or track the car, then they will likely start pulling interior pieces out anyways, place a 5 or 6 point cage, and use race-spec seats anyways.

The engine tweaks can easily be done through the ECU. Cobb looks like there mapping method will be ideal for doing ECU modifications and keeping the Nissan maintenance coverage because the ECU can be flashed back to OEM (purportedly). It looks like the OEM transmission should be able to handle 600 ft/lb TQ pretty easily with little or no modification to the engine, just a tune.

If your racing the GT-R, your going to be replacing the clutches and a differential from time to time anyways. And lots of tires

Carbon-ceramics are really only needed for race applications or if you are hot-lapping at the dragstrip. And who does that!!??*&! Although honestly, I have seen two after-market vendors are offering the same or similar brake pads (i.e. carbon ceramics) for significantly less than OEM.

I'd rather get the base model and make the journey myself. Hell, you can adjust boost to 1 bar (14.5 psi), do nominal weight reduction (e.g. get rid of the complimentary tools under the mat, lose the weight of 11 speakers), and swap some bushings and easily run high 10second 1/4 mile times.

[gts-4 dreamer]

aslong as they use the same start finnish line as lemans used to I will call it a mark... start finnish on the whip end of the straight after the first 'corner' isnt fair.

[SS8_Gohan]

Phoenix, i assume you've popped over from NAGTROC?

looks like you've got some good solid info there, where bouts did you come across it all?

[phunky_monkey]

aslong as they use the same start finnish line as lemans used to I will call it a mark... start finnish on the whip end of the straight after the first 'corner' isnt fair.

I'm confused mate, what do you mean "same start finish line as Le Mans"? It's a different circuit?

[Phoenix AZ]

Phoenix, i assume you've popped over from NAGTROC?

looks like you've got some good solid info there, where bouts did you come across it all?

Not from NAGTROC.

Yes, I have done some research. I enjoy the journey of building very fast street-legal cars, but I really have just looked at all the vendors in Japan and seen what they have posted over the past year. I have seen a ceiling on the clutch packs. I am not entirely clear on what the engine can handle at the limits, but 600 - 615 ft/lb TQ at the crank is probably all I will need to accomplish my goals. I want the car to have some longevity too.

I prefer science over guessing. I plan on making this car run a 10.8 - 10.9 second 1/4 mile on street tires, maybe some sticky R compound BFG drag radials, if needed.

[Phoenix AZ]

This is a quote from a post I made in the British forum.

This is theory. I used very few data points and 3 variables. I considered atmospheric pressure a constant, if you will, because I don't have enough dyno variable sets to incorporate into an equation. [please explain how to use 1.01 in this formula...multiply or divide ) This is a RATIO / PROPORTION grid with a couple conversions. I had 2 data points with which to compare with the factory numbers. Not much to go on. When you consider that different types of dynos (dynapack / mustang & dynojet) are being used at different elevations, yeah sure, it's not perfect by any stretch of the imagination. Plus, people use different octane fuels and measure crank vs. wheel with the other confounding factor of what to use for drivetrain loss (15 - 25%). One other thing, Nissan obviously, did not provide the ideal baseline to work from, because most consumer cars are showing around 435 HP to the wheels. Even with a conservative 'drive-train' loss of 15%, your over 500 HP to the crank.

Additionally, the 'load-type' dyno (mustang / dynapack) requires accurate on-road aerodynamics and friction inputs and the 'inertia type' (dynojet) does not. I think the 'load-type' dynos are GAY, sorry, my personal opinion. I much prefer the dynojet for higher HP applications. Most tuners use the dynapack for comparing baseline (prior to modification) numbers to engine mod; it is fine for looking at change. Dyno jet will give a much closer real-world number.

In terms of the theoretical number projections, this is what I posted originally:

Boost TQ (to the crank)

(bar / psi) lb - ft

0.7 / 10.2 433

0.9 / 13 551

1 / 14.5 618.6

Motor Trend (K+N engineering)

Wheel 430.6 - 435.8 HP, 425.3 - 439.1 lb/ft (range of results)

Projected Crank @ 15% drivetrain loss 506.5 HP / 500.4 TQ

Motor Authority (Dynapack)

475 HP / 428 lb/ft TQ to hub

projected crank 550 HP, 495 lb/ft TQ

Autoblog (Mustang and Dynagay)

406 HP / 414 TQ (Mustang)

452 HP / 448 TQ (Dynapack)

BEST CAR Magazine (JDM [consumer])(Dynapack)

485.665 HP / 428/1 lb/ft TQ (hub)

BP car (running 95-96 US octane rating)

457.7 HP / 444 lb/ft TQ (wheel)

520.5 HP (projected crank)

JSpec Connect (Dynapack)

460 HP, 456 lb/ft (hub)

I believe there is a general consensus that the power of the engine has been under-reported for whatever reason. The numbers given by the factory are probably more accurate (with a proportion given to drivetrain loss) as being wheel horsepower rather than crank horsepower. That is why the numbers seem skewed. Give me better data points, I'll give you better projections.

Conclusions: I don't think it is unrealistic at all for the stock components to give between 550 - 600 ft/lb of TQ (to the wheels) as you approach the drivetrain limits (as given by MCR and Endless) of ~ 14 - 16 psi on the turbo. Heat and efficiency limits considered. And of course, they probably beat the piss out of the car as well.

[sewid]

aslong as they use the same start finnish line as lemans used to I will call it a mark... start finnish on the whip end of the straight after the first 'corner' isnt fair.

The timing method is standardised by Sport Auto magazine and has become the defacto standard for Nurburgring timing across the board and has been adopted by almost all manufacturers.

The start/finish line is no longer used for timing because it is dangerous. The Nurburgring is a public road and cars are constantly entering the track from that area. If you're going all out on a flying lap you're likely to crash into someone at that point.

[fuzzy_scuz]

GTR FTW

[sh@un]

The timing method is standardised by Sport Auto magazine and has become the defacto standard for Nurburgring timing across the board and has been adopted by almost all manufacturers.

exactly

regardless of where the 'proper' start/finish point is, the time Nissan quotes is using beginning and end points consistent with all recent times recorded for other supercars