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Nissan GTR LM Nismo Confirmed for GT Academy Final!!!
- Thread starter fortbo
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Downhill Dino
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I wonder if it'll be used as the final challenge for GT Academy this year. That will make things hard!
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The trick is in the tires width.
I do not expect big understeer.
Everyone can try this:
Take FF car in GT6,put tires with more grip only in front and you will see what will happen.
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Yes, this is a race car, and that is a road car, and that is ALL the difference.
There are plenty of things to be done to reduce understeer, reduce/eliminate bumpsteer, and eliminate torquesteer.
On a road car, the primary goal is comfort. And when you take a Ford Focus, for example, and modify it to run in a series like the BTCC for instance, you are trying to make the car do something it was never designed to do. A Ford Focus was never meant to do 145 MPH regularly, or take 1G+ corner loads repeatedly, or have a big wing and splitter strapped onto it. When you are building a BTCC car, you arent so much building to the strengths of the car, as much as you are trying to find acceptable work arounds for its shortcomings. The biggest being, suspension geometry, engine placement, drivetrain layout, and finally, aerodynamics. All of that is compromise after compromise, desperately trying to stay within the rules to what is allowed from the stock car. Certain aspects of the design simply cant be overcome. The engine is always going to be high, and the placement of the suspension geometry in the chassis is always going to be less than ideal, and on a road car, aero is mostly about trying to make it less brick like, while still being a brick.
When we look at the Nismo LMP1, we have none of those shortcomings, because there is no reason to compromise. There is no stock car to adhere to dimensionally. There is no stock engine placement. There is no stock suspension geometry. There is...nothing. This is a bespoke prototype. It is a one off car. And as such, there is no limitation to the engineering that can be done to overcome any inherent shortcomings of the FWD layout.
For starters, the engine is moved rearward of the wheel centerline. Where as in most FWD road cars, it is right over the wheel centerline. In racing applications, like the BTCC again, they often rotate the engine rearwards to cheat the weight a little lower and further back. The LMP1 doesnt have to worry about this. The engine is already incredibly low, and set amidship for better weight distribution.
Second, and probably most important, is the suspension layout. In a road car, the suspension is designed for durability and comfort first, and then performance after the fact. Things like struts are used in order to make the assembly process easier, and the materials and parts costs cheaper. Struts are far from ideal, and have multiple shortcomings and compromises. In the LMP1 setup, there is no need to use any kind of "conventional" production suspension layout. So you can start with geometries that make sense for removing quirky FWD handling oddities. So you can make the front suspension work better, and use geometries that will allow for front wheels to not be overworked, or over stressed. Because there wont be the problem with massive understeer, or bumpsteer, or torquesteer under acceleration. The same is true for the rear suspension. It can be designed and tuned to match the requirements of the front suspension, again with no design constraints to shoehorn them into trying to make something that doesnt work, work well enough.
And we havent even bothered to talk about how the aero package is devoted to making the front of the car work, and all of the innovations there in the cars design that allow for them.
Really, trying to quantify the handling of the LMP1 in any way to a road car, is like trying to draw parallels between the Audi R18, and a semi truck, because they both use diesel engines.
You can bet that if they couldnt engineer their way around the perceived shortcomings of a FWD layout, they wouldnt have stuck with it like they have. Clearly they have been able to manage it through design, and have seen great results. So i have no reason to believe that it wont handle jsut as well as any of the other P1 class cars out there.
Torque steer is primarily a function of differential biasing through unequal length drive shafts. Secondary causes can be flexible engine and transmission mount, as well as uneven suspension deflection while accelerating.
I would put money on the LMP1 having, not only equal length drive shafts, but also having a differential that manages torque load, as well as a suspension geometry that doesnt allow for deflection, or bump.
In other words, this is a pure prototype racer, engineered from the ground up to be FWD. Addressing any of the inherent issues with FWD, would have been addressed right from the start.
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Oh... just a thought... if that was a diesel guzzling 3.5L Twin Turbo V6, I could only imagine the power output and torque when combined with the electric motors. Instead of 1,000 hp bursts from the electric motors, it would be around 1,220.
It could have at least 975 lb•ft of torque.
It could have at least 975 lb•ft of torque.
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... mostly going to the rear wheels. And I think your estimates are well below reality - the petrol engine is a 3.0 twin turbo V6 and likely to have around 425lbfft bunched in the middle, while the electric motors will, if they're as powerful as suggested, be shovelling a few thousand lbfft.
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Oh yeah, instant torque from a normal electric motor. This isn't the same car, but flashing the ECU from a Pruis gives 1,300 lb•ft of TQ as soon as the accelerator is tapped. It's amazing.
I can only think of it.
3.0L Twin Turbo V6
-Premium Diesel
-800hp combined
-3,200lb ft combined
3.0L Twin Turbo V6
-113 Octane Gasoline
-650hp combined
-2,000lb ft combined
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It's still ugly from almost every angleHope they have some trick up their sleeve to make turn the FWD into an advantage otherwise epic fail.
Is this when we should point out that Traction Control is allowed in LM P1 HY?
This
They haven't confirmed the HY power output in fact Darren Cox refused to discuss it during Radio Le Mans.
I doubt they would be able to get the power that high with a diesel set up. For starters the fuel flow restrictions on diesel powered cars is much more strict.
And, contrary to popular belief, the power output of a diesel engine has a much narrower band than that of a gasoline engine. Audi has made some great strides in improving the drivability of the diesel in the R18, but the original R10 diesel engine was a bit of a hand full, many drivers reffering to its power delivery as an on off switch. At low revs with no power, then suddenly massive torque, that would quickly bleed off with more RPM. So it became this odd throttle balancing act, and having to adjust your way of driving the car entirely, so you could maximize the power of the massive torque.
But, as the regulations stand now, you get a little more working room with a petrol powered engine, so there is more opportunity to make bigger power. Not to mention the petrol engines will be a bit more conventional to the drivers who use them.
Many of the specifics are not out yet, however, we do know that it is a flywheel based kinetic hybrid system, and that it is powering the rear wheels through a driveshaft, and individual transfer housings on each wheel.
You can read more about it here.
http://www.roadandtrack.com/motorsports/a24902/developing-the-nissan-gt-r-lm-nismo/
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@Buck-O - Instead of making one post after another to respond to different people, please use the "+Quote" button to queue up quotes or highlight sections of posts and hit "Reply" from the pop up menu to add shorter quotes to the reply box automatically.
Incidentally, the torque output of a 600hp electric motor at 500rpm is 6,300lbfft. Think bigger.
It's still petrol.
NISMO
Incidentally, the torque output of a 600hp electric motor at 500rpm is 6,300lbfft. Think bigger.
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Assuming it was a DOHC design with 4 valves per cylinder, Variable Valve Timing and Lift would have been an option. If you use that plus a finely tuned cam profile and pistons with around a 16.5:1 compression ratio (for diesel) to your advantage, your power curve would be a diagonal line across the graphs. Sure it costs a lot to develop, but it could be worth it in the end.
/on-topic
Hopefully this Nissan GT-R LMs' petrol engine ends up being the following:
3,026cc, 60° V6, DOHC 4 Valves Per Cylinder (VVT/VVL), Direct Fuel Injection, 30-35 PSI Boost
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vasiliflame
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Well it's not a looker but FF 600bhp is something. I like to see it corner. i had a 205 gti that torque steered really bad when it was around 170 bhp can not imagine 600 bet they got some gizmos though
Youre forgetting to factor in restrictors. That changes everything. Currently petrol restrictors are more open. That, along with the added fuel flow, means you can be a little more choosy with the turbo selection, and allow you a little ore fuel mapping options.
The rules have really started to clamp down on diesel, and unless you REALLY want to pander to that side for marketing, like Audi, it just makes more sense to run a petrol engine from a pure power standpoint.
Ive said it before, and i will say it again...
No.
Because posts and comments easily get lost that way, and the notification system often only notifies the first quoted person, and not the second. And more often than not, the second quoted person wont bother to read through the first users reply, to even realize that he has been quoted as well.
This becomes doubly frustrating when you are separating out individual segments of a single users posts for better clarification, and end up with multiple quote boxes in a reply. Tagging a second, or third users quotes onto the bottom of that, virtually guarantees they will get overlooked.
Case and point, even though you user tagged me, i got no notification, because your initial quote was to TheProRacer.
The system is fundamentally flawed, and until it is fixed, there is absolutely no reason to combine posts together at all.
Especially considering that i usually do not give short replies, combining posts makes them unrealistically long, and cumbersome.
Each post is an individual thought process for that particular reply, and keeping them separate better communicates that fact to the user.
It is a poor policy, and it should change.
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Then I'll remind you that it is not a request.
That's not correct. All people named and tagged in a post get notified of the post when it is created. They do not if it is edited after submission.
No, it was because I edited that section of post in - unfortunately you double-posted as I was responding to @TheProRacer and didn't check the new posts before I submitted. Had it been in the original post, you would have been notified.
Then request of @Jordan that it be changed. In the meantime I'll reiterate - it is not a request.
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No. I told you how the circumstances you describe are false - ALL users tagged in the post on its initial creation are notified, contrary to your claim that only the first quoted person is notified. It is when more users are edited into already created posts that notifications do not occur - so your objection to multiple quotes is not apt.
Now you have more accurate information that dismisses your primary listed concern and have been made aware of the rules you are required to follow, this particular side discussion is done. If you still wish to discuss this matter, contact @Jordan
Back to the Nissan.
Can anyone please explain how Audi and their diesel engine manages to stay competitive despite all the energy and fuel handicaps they have? I assume it's an inherent advantage of diesel fuel but I'd like to get a clear-ish explanation if anyone knows...If anyone wants to see the flow regs I know @Famine loved this stuff (btw you going again this year?)
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Still puzzled as to why it is FF. 
Is it to show off or will it be practical? Will the front tires explode with the force of a nuclear bomb during the race under all that power?
Is it to show off or will it be practical? Will the front tires explode with the force of a nuclear bomb during the race under all that power?
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This thing baffles me. On paper this car is back-to-front with the engine, drivetrain and width of the tyres all being the wrong way around. I will be at Silverstone to see this thing in the flesh, and I am looking forward to that. I personally think that from certain angles (notably the front) that it is a beautiful thing.
I'm sure that Nissan knows what they are doing... Probably... Maybe... I'm not sure...
I just hope that it is more reliable than the DeltaWing.
I'm sure that Nissan knows what they are doing... Probably... Maybe... I'm not sure...
I just hope that it is more reliable than the DeltaWing.
R5
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FTFY
CodeRedR51
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Why is everyone oblivious to the fact that the car is actually AWD under corner exit acceleration?Still puzzled as to why it is FF.
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Most don't know anything about what a hybrid P1 and how they are made to work...
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Still puzzled as to why it is FF.
One word...Packaging.
It allows there to be absolutely no drive train components, or suspension parts, inside the rear venturi tunnels of the rear diffuser. So the airflow has maximum velocity with minimal obstruction, which will allow for greater downforce at all speeds, and significantly reduced drag. It is why, compared to other P1 cars, it has such relatively low rear wing profile. Most of the rear downforce is coming from the underbody, not the wing.
There are also likely to be benefits to the pressure recovery of the front diffuser, improving its efficiency. As well as the "flow through" body design further aiding in drag reduction, and pressure recovery out the back of the car.
The FF layout was almost incidental to the development of the airflow channeling out the back of the car.
As for the tires, they should be fine. They are a bespoke Michelin tire for the car. They have the same overall diameter as the other P1 tires, but unlike the 18" wheel everyone else runs, the Nissan will run 16" wheels. This gives the tire a little more sidewall, and allow for a bit more compliance, and slip angle, as well as a little rotating mass reduction. I would guess that Michelin has a compound for the fronts, that is similar to the rear tires on the rest of the P1 field, with improved construction to cope with the riggers of acceleration.
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Any word from Darren @DSkywalker01 ?
