The creator of GTR explains how the GTR is so heavy

[EndLeSS]

Taken from my local car forum:

From the designer drawing board itself. Not all aftermarket like 600hp stripped GTR(lighter) can do a better time than the stock GTR in the nurburgring. That wt has a purpose. A 600hp GTR will be faster in straight line but in Nur time might be different. It is a better package car. If you want a dragster make it 800hp good for straight line but not for Q day use.

NISSAN GT-R: KAZUTOSHI MIZUNO INTERVIEW
Part I of PH's exclusive video interview with the Nissan GT-R program chief

Last month PistonHeads was invited to visit Nissan's Nurburgring Technical Centre for an exclusive interview with the 'father of the GT-R', the car's program manager and chief engineer Kazutoshi Mizuno.

PH Editor Chris-R posed questions based on suggestions from the PH forums, and we captured Mizuno san's answers on camera. Check out the film clips below, for some fascinating insights into the mind of this famously single-minded chief engineer, and his philosophy about the GT-R project.

The fount of all GT-R knowledge very kindly answered all our questions in English, making frequent use of the office whiteboard to illustrate various points.

Without blowing the PH trumpet too loudly, we're forced to say that GT-R 'geekery' doesn't get much better than this. So pay attention class, and take it away Mizuno san..

Q1) For such a high performance machine, the GT-R is a big car and heavy one. Tell us why that is?

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Q2) So what is the best way to reduce weight from the R35 to make it perform better?

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Q3) In your previous answer, you seemed to be telling us the parameters of 1700kgs weight and 485hp were set from the beginning of the project, is that correct

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Q4) Why did you opt for a V6 engine, instead of an engine with more cylinders?

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Q5) What about the transaxle - some competitors have seven or eight speeds, so why does the GT-R have only six?

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Q6) The R34 had the HICAS rear wheel steering system. Why didn't that make it onto the latest GT-R?

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[tosugrad]

So he basically says (in the first clip) the car is a heavy pig so it can handle better. Thats what he says!!!!

Unbelievable!

 

[FXMDBilly]

So he basically says (in the first clip) the car is a heavy pig so it can handle better. Thats what he says!!!!

Unbelievable!

+1

Ridiculous... I can't believe Nissan allowed this to air.


Edit: And the twin turbo V6 was chosen because it matches the weight of the transaxle. I'd be surprised if that was true.

 

[swerve2007]

i guess if you can't tune the suspension and power delivery you throw a bag of sand in the trunk.

 

[FXMDBilly]

i guess if you can't tune the suspension and power delivery you throw a bag of sand in the trunk.

Quit giving away our secrets!! :wink:

 

[amgnsx]

did'nt bother to watch the rest.

what a total idiot

in the first few sec on the the first clip

he ses "F1 car weight 600kg and it has 1000kg down force, so when the the F1 turns the car weights 1600kg."
WTF!!!

what a complete IDIOT

after hearing that i just paused the video and spared my self. :biggrin:
i'm soooo glad he does not work for HONDA.

 

[Gansan]

Guys, I think you have to understand where he's coming from, and also take into account some of his phrasing (which sometimes sounds like Japanese translated in a literal manner into English).

Mizuno clearly knows that lighter is better for performance, but he's willing to sacrifice that if it means he can work around the weight while attaining other less tangible performance goals such as non peaky--as in "not twitchy"--responses and good feel. The weight dampens responses so that the average middle-aged guy can strut around thinking he's Sebastian Vettel. You can see the result of this thinking when people talk about how the car is easy to drive fast. It's not as if the resulting car completely contradicts what Mizuno is saying.

 

[Aaron94T]

Guys, I think you have to understand where he's coming from, and also take into account some of his phrasing (which sometimes sounds like Japanese translated in a literal manner into English).

Mizuno clearly knows that lighter is better for performance, but he's willing to sacrifice that if it means he can work around the weight while attaining other less tangible performance goals such as non peaky--as in "not twitchy"--responses and good feel. The weight dampens responses so that the average middle-aged guy can strut around thinking he's Sebastian Vettel. You can see the result of this thinking when people talk about how the car is easy to drive fast. It's not as if the resulting car completely contradicts what Mizuno is saying.

+1, We are talking about the GTR here. It doesn't just talk the talk. If you are not driving a new ZR1 or new SRT-10 you will not be faster than the GTR around a track, stock for stock. It does all this while giving up well over 100hp and many hundreds of lbs to those cars.

I thought the videos were very interesting. You have to take them with a grain of salt as he is always going to justify the final result. However, with the GTRs performance he does not have to make many excuses.

With all that said, no stick, no want. :tongue:

 

[DeNguyen]

Guys, I think you have to understand where he's coming from, and also take into account some of his phrasing (which sometimes sounds like Japanese translated in a literal manner into English).

+1 Engrish not so good...

I kinda don't really care about what he said, just because his end result its pretty badass. Ugly, but badass...

Maybe hes just trying to throw everyone off??

 

[DeNguyen]

after hearing that i just paused the video and spared my self. :biggrin:
i'm soooo glad he does not work for HONDA.

if he worked for honda, we would have a new sports car that competes with some of the best in the world.

are you sure you're glad?

 

[Hasdrubal]

Just imagine how much better it would be without the weight. The key to the GTR's speed is the all wheel drive system and associated computer wizardry. It's not as if you can make the NSX a better car by adding turbos and nine hundred pounds of ballast.

 

[cmhs75]

OK, I'm going to be the idiot here so please indulge me



is it true that F1 cars weigh 1600 kg going into corners?

 

[RStom - Hungary]

OK, I'm going to be the idiot here so please indulge me



is it true that F1 cars weigh 1600 kg going into corners?

YES!
But you have to be aware of 2 things:

• mass: is the tendecy agains the acceleration. F=m*a Where "m" is the mass "F" is the force and "a" is accelereation. with the same force if the mass is smaller the acceleration is bigger
• weight: Is the force how the object push the floor os pull the ceiling...

So the two thing is not equal, and that is whay the combination is good in the case of the F1 car. Tha mass is still 600kg so with the same force the acceleration is bigger, but the weight is 1600kg which is better for the stomping. (Az the friction force is equal F=u*F' Where "u" is the surface coefficinet "F'" is the compulsion force in this case is the weight...so the bigger the weight the bigger stomping force could be achieved!

 

[gdae]

Well, that cleared that up.

 

[colslaw87]

I think those videos were great.

To all the people who contradicted him...you know your doubting the "creator of the GTR"? He helped design Godzilla, I think he knows what he's talking about. It's not like he's a Marketing douche who doesn't know the first thing about cars.

I wouldn't put his knowledge past me. He definitely explains the correct way to achieve good performance with light weight.

 

[swerve2007]

it just proves yet again how special nsx is- to make a lightweight car feel 'supple' and 'uneventful' is not easy. i understand that some of us, myself included, would like that 'edgy' feel and power delivery sometimes but that does not translate into faster lap times. afterall it is about driver confidence, you can push way past the limits of your camry on the track (yes, you know which one, lol) yet be more comfortable doing it than driving a ferrari at 8/10s.

 

[bambbrose]

What he is saying is certainly true, but he is simply looking at the side view, and not the top view as seen when taking a corner.


Looking at the car horizontally as he describes, the weight of the vehicle as well as the downforce are summed in the free body diagram.

You have gravity pulling down and downforce pushing down. The force on the ground that opposes these two forces (normal force) is equal and opposite to these two forces, and therefore the grip of the tires is directly related.

The part he didn't draw is the view from above while taking a corner.

In that situation, the corner has a radius of curvature "R" and a sweeping angle theta. In this situation you have the intertial forces to deal with (centrifugal forces to the general public). The mass will want to continue along its original path and not take the turn.

In this situation, the grip of the tires is a force pushing to the inside of the curve, whereas the inertial forces induced by the mass are trying to pull to the outside of the curve. If the forces pulling outside are greater than those pulling inside you lose control. In this situation, the weight of the vehicle is very disadvantagous because the inertial forces follow "mass*(R*(d theta/dt)^2)" which is non-linear. This plays a much larger role in determining grip as the acceleration is increased. For smaller accelerations he probably is right, but at the limit the inertial forces are more important.

I believe that is what RStom - Hungary was getting at.

The F1 car might have a downward force of 1600kg when looking at the horizontal view just as the GTR does, but when looking at the top view, it only has the 600kg mass, but still gets the full grip as if it had 1600kg, which is why they corner so well.

 

[heySkippy]

is it true that F1 cars weigh 1600 kg going into corners?

Think of it as if the car was on a scale at the time. All that downforce would register, no?

 

[Mr Payne]

+1, We are talking about the GTR here. It doesn't just talk the talk. If you are not driving a new ZR1 or new SRT-10 you will not be faster than the GTR around a track, stock for stock. It does all this while giving up well over 100hp and many hundreds of lbs to those cars.

I thought the videos were very interesting. You have to take them with a grain of salt as he is always going to justify the final result. However, with the GTRs performance he does not have to make many excuses.

With all that said, no stick, no want. :tongue:

1) ZR1 is faster than the GTR. Nurburgring, etc. I don't think the SRT-10 has ever been in a comparo with a GTR, but an ACR is easily faster than the GTR (as a no-compromise beastly street car should be).
2) The weight doesn't help the GTR. I'd reckon the GTR has the most advanced AWD system on the market and maybe the most advanced active suspension on the market. That's where the GT-R seems to 'outperform' it's power to weight.

 

[ChopsJazz]

Thanks for those great videos, but this is still my favorite:

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[NetViper]

I hear they are making a special heavyweight version tuned for the track.:biggrin:

 

[cmhs75]

I hear they are making a special heavyweight version tuned for the track.:biggrin:

LOL good one

 

[6spd_legend]

The fact that some of you are calling this guy an idiot is actually hilarious....

 

[UnhuZ]

Hi,

yeap... i find that amazing my self...i mean..as if the guy doesn't have a clue and the final GT-R superior performance came by accident .... pleeeeeaaaaseeee try to be humble and learn what he is trying to teach... instead of reacting against what he said, try to understand it....

Nuno

The fact that some of you are calling this guy an idiot is actually hilarious....

 

[Aaron94T]

1) ZR1 is faster than the GTR. Nurburgring, etc. I don't think the SRT-10 has ever been in a comparo with a GTR, but an ACR is easily faster than the GTR (as a no-compromise beastly street car should be).
2) The weight doesn't help the GTR. I'd reckon the GTR has the most advanced AWD system on the market and maybe the most advanced active suspension on the market. That's where the GT-R seems to 'outperform' it's power to weight.

Did you read my post? I said if you are not driving a ZR1 or SRT-10. Meaning they are both faster. BTW the ACR holds the Nurburgring record and I have read all about it and talk to many proud Viper ACR owners about it. The list of faster track cars than the GTR is very short. Those two however, are on it.