[Jackygor]

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?

http://www.youtube.com/watch?v=8nGiZKQmODA&feature=player_embedded


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

http://www.youtube.com/watch?v=x1izuj3ku8k&feature=player_embedded

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

http://www.youtube.com/watch?v=eXtOYrL67Fo&feature=player_embedded

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

http://www.youtube.com/watch?v=Nf8rADuMcLM&feature=player_embedded

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

http://www.youtube.com/watch?v=bc5wIKGnC0k&feature=player_embedded

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

http://www.youtube.com/watch?v=gil9Utvq2GM&feature=player_embedded

[zilla510]

very good videos and informative

[crazyazn]

cliffs?

[trancehead]

Great post

was hard catching all of it when he described the reasoning behind the v6. basically balance?

[124Y]

Wow... nice videos!

[Mugen EvOlutioN]

cant really understand his english 100% but oh well



so basically he is saying light weight is good, he understands that..ok...

light weight better for acceleration and breaking, but you want heavier weight for cornering speed?

[impactX]

Mechanical grip through deadweight?

FYI, if the F1 teams were allowed, by regulation, to run lighter than 600kg, they would.

[skyxx]

cant really understand his english 100% but oh well



so basically he is saying light weight is good, he understands that..ok...

light weight better for acceleration and breaking, but you want heavier weight for cornering speed?

He's saying you can't get the same downforce as F1 cars or any racing spec cars. So they substituted extreme aerodynamics with actual weight so when you corner there's more grip on all 4 corners of the car by having the weight with the added downforce. That in turns create a similar weight acting upon the car as an actual race car. Something like that...

[toyota86]

That was interesting to watch. It feels like they are trying to make the new gtr too balanced by trying to make it able to do everything. I don't think a car that is too balanced and tries to do everything can be a real sports car.

[death_blossom]

Mechanical grip through deadweight?

FYI, if the F1 teams were allowed, by regulation, to run lighter than 600kg, they would.

I agree, the whole dead weight argument seems to be the only explanation? he never mentioned how you could get more cornering grip through aerodynamics. which is exactly how F1 cars achieve their cornering grip.

I would have liked it on how the body is reinforced and put together. that there, is probably another big part on the great chassis of the R35.

[Nightwalker]

I agree, the whole dead weight argument seems to be the only explanation? he never mentioned how you could get more cornering grip through aerodynamics. which is exactly how F1 cars achieve their cornering grip..

He says in the clip that they're making a normal roadcar. They had no intention of trying to generate that kind of force through aerodynamics on a regular car.

[chunk_stir]

very interesting video to see what design constraints the R35 was built around. The PH questions were centered around the assumption that the R35 could be so much better and faster if it was lighter and had more power (typical go-fast mods people do to the car).

But from the point of the designer, the application of the car being:
-non-professional drivers
-not high-speed where down-force is a major factor in contributing to the grip of the car
-varied driving conditions: snow-covered road vs dry track conditions vs rainy highway

And the design starting point was the contact patch of the tire, assuming a 20" tire. The car was built around the contact patch --> goal of 50/50 weight --> engine choice --> transaxle complexity --> etc....

Amazing to see the engineering thought process that guy goes through!

Obviously, if you want the car to go faster for a specific application, then you sacrifice one of the other design values.... For racing (especially WRC), teams can afford multiple setups (and cars) to customize for each race environment... but for most owners where the car is also their daily driver, then this car appears to have been well thought out... whether people like it is another thing....

[impactX]

He says in the clip that they're making a normal roadcar. They had no intention of trying to generate that kind of force through aerodynamics on a regular car.

Well, if it's a "regular car", why would it need a fast time on the Nurburgring?

I wonder, with that much weight torturing the tires through the corners, how consistent are GTR-R35's laptimes on the Nurburgring on like a 5-lap stint compared to a 1-lap flyer?

Can an engineer on here explain to us, assuming that the GTR-R35 has x unit of grip, if a lighter car needs more or less than x unit of grip to enter, go through, and exit the corner at the same rate of speed?

[dutch]

He's saying you can't get the same downforce as F1 cars or any racing spec cars. So they substituted extreme aerodynamics with actual weight so when you corner there's more grip on all 4 corners of the car by having the weight with the added downforce. That in turns create a similar weight acting upon the car as an actual race car. Something like that...

lighter is always better. the reason is when you go through a corner you have lateral load.

if you have a 2000 lb car vs a 3000 lb car with the same tire contact patch, the lighter car will corner faster because there is less weight in the lateral load.

his argument is that more weight is better in all conditions (dry, rain, snow), and of course he's trying to make it look good (its his baby).

I'm afraid all the gtr fan bois are going to think heavy cars are better.

the weight of the gtr is a side effect of the awd system. Anybody who preps are gtr for racing will strip it out to "add lightness".

[!Aznboi128]

good info!

[Jackygor]

I remember there is a part where he mentioned that lighter cars ARE faster, but they are harder to maneuver? Perhaps its more twitchy?

[ronald55555]

Well, if it's a "regular car", why would it need a fast time on the Nurburgring?

I wonder, with that much weight torturing the tires through the corners, how consistent are GTR-R35's laptimes on the Nurburgring on like a 5-lap stint compared to a 1-lap flyer?

Can an engineer on here explain to us, assuming that the GTR-R35 has x unit of grip, if a lighter car needs more or less than x unit of grip to enter, go through, and exit the corner at the same rate of speed?


His arguments make absolutely no sense. His comparison of the F1 and GTR free body diagram may make sense, but when you try to do it on the lateral axis, it all falls apart.

F=ma (force = mass times acceleration)
In our case, acceleration is the centripetal acceleration, mass is mass of the car, force is lateral force from the tire. If an F1 and the GTR goes through the corner at the same speed, they have the same centripetal acceleration, so to answer your questions, the light car needs less lateral force from the tire. If the gtr is 3 times heavier, it will need 3 times as much lateral force(ignoring aero effects). Of course, that was all simplified to highschool physics, there are much more going on, but even the gtr can't defy the laws of physics.

The other point he made about the tire contact patch area is true, but it is a fact that lateral force does not increase linearly with increasing load. ie if the gtr is 3 times heavier than an F1, and they have the same tires, and ignore all aero effects, the gtr does not have 3 tires more grip.

[chunk_stir]

Well, if it's a "regular car", why would it need a fast time on the Nurburgring?

I wonder, with that much weight torturing the tires through the corners, how consistent are GTR-R35's laptimes on the Nurburgring on like a 5-lap stint compared to a 1-lap flyer?

Can an engineer on here explain to us, assuming that the GTR-R35 has x unit of grip, if a lighter car needs more or less than x unit of grip to enter, go through, and exit the corner at the same rate of speed?


It's been years since engineering school, and I'm no longer doing engineering as a professsion... but from what I recall (perhaps someone else here is more knowledgeable)...

Part of the Engineering discipline is breaking down a number of complex interactions into tangible elements. The Chief Engineer (CE) for the R35 broke down some of the "priority" elements in the videos. He started at friction of the contact patch.

traction = friction = coefficient of friction (a property of the materials in contact) x downward force (aka weight).

So based on that equation, maximum friction comes with greatest downforce (weight) multiplied by the friction coefficient of the tire. Hence, his argument that greater weight is better for traction. He did say lighter weight is better for acceleration and braking(I think?)...

However, the CE simplified the model by only working in 2D (front and rear axles). In a turn, you have the side-to-side forces at work as well (outside-wheel vs inside wheel). A lighter car (as well as location of center of gravity - CG, and suspension design, etc.) will affect how much weight shifts from inner to outer tires. Once this downward force on the tire exceeds the coefficient of friction limits of the tire, then you get slip.

But think about it, tires have to handle a lot. (If you took a motorcycle riding course, they actually explain it pretty well). But for a car, in a turn, your outer tires have to handle: 1) acceleration/deceleration forces, ie. force in line with the direction of rotation of the tire, 2) side-to-side forces, ie. the tendence of the car's CG laterally on the tire, and 3) The front-rear shift in weight on the tire. and 4) the increased downward load from the side-to-side weight shift from inner tires to outer tires.

So taking the model to the extreme... Forces 3 and 4 above add to traction of the tire, while 1 and 2 fight against it. When F1 and F2 > F3 and F4, you lose traction... Now that's on one tire. So if you took the extreme case, where you were accelerating to lift the front wheels (pitch) and turning to lift the inner wheels (roll) so that all the cars weight was on the rear, outer tire, you would reach the maximum traction of the car on that tire. If F1 and F2 were less than this, then you would maintain traction. But those aren't the only forces in play because we've got four corners on the car... You also have the car's rotation to account for as well (yaw), which adds twisting force on that tire.

In any case, what I think I'm trying to say is that analyzing the handling of the car is complex. I think he simplied his explanation greatly for the purposes of the questioning. He wasn't dealing with engineers and car designers... Did you see the interviewer roll his eyes when the CE went into explaining reasoning for not using super-hicas? The CE started at a simply "priority" in his design and built out from there to answer all of PH's questions.

[SolidPenguin]

I remember there is a part where he mentioned that lighter cars ARE faster, but they are harder to maneuver? Perhaps its more twitchy?

Yah, thats where he mentioned the part with professional drivers and the amateur drivers the GT-R is meant for.

"Iz berry impotant, ok?"

He said that every other line.

[chunk_stir]

lighter is always better. the reason is when you go through a corner you have lateral load.

if you have a 2000 lb car vs a 3000 lb car with the same tire contact patch, the lighter car will corner faster because there is less weight in the lateral load.

his argument is that more weight is better in all conditions (dry, rain, snow), and of course he's trying to make it look good (its his baby).

I'm afraid all the gtr fan bois are going to think heavy cars are better.

the weight of the gtr is a side effect of the awd system. Anybody who preps are gtr for racing will strip it out to "add lightness".



I think I know what you are saying, but again it's reflective of oversimplification of the dynamics involved in car design.

Yes lighter can be better, when designed well within the overall constrainst of the car and what you're trying to achieve. eg. you prep a car differently for short auto-x runs on dry asphalt vs high-speed and endurance lemans race vs driving in the snow-covered country road to visit your uncle's hunting cabin.

If you only focus on lightening the car and cramming a v10 into the engine bay, without considering your spring-rates, dampening, even gear ratios, you likely will have a poorer-performing car because the car will sit higher and bounce around on the bumps --> lose traction (his starting point).

Actually, using your 2000 lb vs 3000 lb example, theoretically, and making the following assumptions:
-equal driver input
-ignoring aero-loads
-equal ratios of weight shift between front-rear (pitch), side-side (roll), rotation (yaw) - these are dependent on suspension design and weight distribution of the major components and chassis
-equal contact patch distribution amongst 4 wheels (suspension and chassis design)
-equal power to weight-ratio (engine selection)
-equal power band of the engine (gearing selection and engine design)
-same tires
.... the two cars should have same speed through the turn and reach max traction at the same time.

What the CE kept saying was "the package" of the car. there are so many constraints in the design of a vehicle and depending one what is a priority, you build around that priority and try to stick within the constraints you set out with. If he was looking to build a competitor to the Lotus Elise or MRS spyder, I'm sure the car would have looked a lot different.

I am by no means a fanboi.... I just appreciate solid engineering design

[.Renn.Sport]

I remember there is a part where he mentioned that lighter cars ARE faster, but they are harder to maneuver? Perhaps its more twitchy?

thats exactly the point.... who doesn't know lighter cars are faster. thats if the average driver could control it in the first place. Light cars aren't exactly easy to drive.

they are making a street car, not a dedicated race car for pro-drivers

[Rikaro]

I'm not a big gt-r fan myself. But I have to say the designer has it's own concept for designing a fast car and it worked. Proved that heavy cars can corner faster if it's done correctly. Obviously it's not like if you put 200kg on your front tires on your Toyota Yaris, it's going to make it corner faster. It's all about the engineering.

[dutch]

Actually, using your 2000 lb vs 3000 lb example, theoretically, and making the following assumptions:
-equal driver input
-ignoring aero-loads
-equal ratios of weight shift between front-rear (pitch), side-side (roll), rotation (yaw) - these are dependent on suspension design and weight distribution of the major components and chassis
-equal contact patch distribution amongst 4 wheels (suspension and chassis design)
-equal power to weight-ratio (engine selection)
-equal power band of the engine (gearing selection and engine design)
-same tires
.... the two cars should have same speed through the turn and reach max traction at the same time.

I don't agree, read the book "how to make your car handle"

http://www.amazon.com/How-Make-Your-Car-Handle/dp/0912656468

I even got some pages on this subject for you:

http://northwestmr2.com/incoming/dutch/pictures/1.gif
http://northwestmr2.com/incoming/dutch/pictures/2.gif

I agree they built one hell of a car. But he's selling the cars weight as a good thing. The car is actually very heavy by many peoples standards, including Nissan.

Thats why they are building the vspec which will apparently be 150kg lighter.

[124Y]

That was interesting to watch. It feels like they are trying to make the new gtr too balanced by trying to make it able to do everything. I don't think a car that is too balanced and tries to do everything can be a real sports car.

This is what makes the GT-R unique, along with Evos and STIs. Fast on any surface in any condition.

[hk20000]

I don't agree, read the book "how to make your car handle"

http://www.amazon.com/How-Make-Your-Car-Handle/dp/0912656468

I even got some pages on this subject for you:

http://northwestmr2.com/incoming/dutch/pictures/1.gif
http://northwestmr2.com/incoming/dutch/pictures/2.gif

I agree they built one hell of a car. But he's selling the cars weight as a good thing. The car is actually very heavy by many peoples standards, including Nissan.

Thats why they are building the vspec which will apparently be 150kg lighter.
the Vspec is already on the market and it's only down by 60kg due to the ceramic brakes and the TE37 Spec II on the car.

Vspec is supposed to be more of a track day toy than the regular GTR though, which means less weight IS better.

I can understand where he came from, he puts on all this dead weight because GTR is a "multi-performance super car" it's meant to be driven 365 days a year be it rain or snow. Hence at lower speeds and traction conditions this car has to work without downforce. Like someone said, this car has to work like a WRC car without actually getting its settings changed around with the environment....so a massive car is easier for the drivers to handle in those situations.

[chunk_stir]

I don't agree, read the book "how to make your car handle"

http://www.amazon.com/How-Make-Your-Car-Handle/dp/0912656468

I agree they built one hell of a car. But he's selling the cars weight as a good thing. The car is actually very heavy by many peoples standards, including Nissan.

Thats why they are building the vspec which will apparently be 150kg lighter.


That's good stuff... Definitely explained better.

But yes, taking a step back from the theory, the GT-r is a pig. Could it be lighter? Sure... I guess that's why the y have the V-spec coming out... But did they market it that way so they could sell more units and give a sense of exclusivity, or because they actually realized they built a pig of a car after spending millions in development? I think it's the former, not the latter.

Bottom line for most carmakers (especially mass ones like Nissan) is not building race/track cars... they build them to sell for a certain volume where they can make money. And how they do that is to give the impression to buyers that they are buying a genuine race-car so that fanboys will pony up with the bucks for the car.

So they build them with certain design constraints with $X of development costs. In this case, the CE chose to start with "The GT-R has the same 'static weight' as an F1 car with aero-load at full speed". I think that is what is slightly ridiculous about the starting point of the design.

But they designed it well around that starting point...

[hk20000]

That's good stuff... Definitely explained better.

But yes, taking a step back from the theory, the GT-r is a pig. Could it be lighter? Sure... I guess that's why the y have the V-spec coming out... But did they market it that way so they could sell more units and give a sense of exclusivity, or because they actually realized they built a pig of a car after spending millions in development? I think it's the former, not the latter.

Bottom line for most carmakers (especially mass ones like Nissan) is not building race/track cars... they build them to sell for a certain volume where they can make money. And how they do that is to give the impression to buyers that they are buying a genuine race-car so that fanboys will pony up with the bucks for the car.

So they build them with certain design constraints with $X of development costs. In this case, the CE chose to start with "The GT-R has the same 'static weight' as an F1 car with aero-load at full speed". I think that is what is slightly ridiculous about the starting point of the design.

But they designed it well around that starting point...
I don't think the $$ part comes into play at all for the GTR....it's supposed to be no bars held when that French guy was CEO he just wanted the halo car back.

The problem is that a GTR is not in the same market as a Pagani Zonda or Ferrari Enzo.... they serve different purposes, and therefore must be packaged differently.

If all that you want to do is beat a 911 GT2 around the ring, you can get away with a simple chassis and that GTR engine and call it a day. But GTR has to carry the torch all the R32 R33 and R34 has passed down: Be fast, and be fast in any situation. In the 21st century where the average driver could buy a GTR and run it up Vancity, a car that works in the hands of a ham-fisted driver is required for it to market well, especially when Nissan wanted to mass produce it without a limited production number, sold worldwide.

Like he said, and I know, a lighter car is hell of fun but a heavier car is safer and easier to handle for amateur driver.

It's both a fortunate and unfortunate trend to sports cars, fortunate is that sports cars are now engineered to be less intimidating, unfortunate is that feather weight sports car will be a thing of the past. I don't expect the FT-86 to be feather weight either. If you make the old AE86 using that 25 year old blueprints, majority of the potential buyers are going to deem it unsafe and "flimsy" and twitchy. Just look at how the Mazda Miata has "grown fat" over the decade.

[jtanner_]

Wow nice find and good read through this thread...
Posted via RS Mobile

[Timpo]

I CAN NOT BELIEVE HOW FUCKING DUMB MR.MIZUNO IS!!!!

Seriously, let's use his example.

The F1 car weighs 600kg, making 1000kg downforce.
GT-R weighs 1600kg(I know it actually weighs more, but whatever) and making 0 downforce.

ok so let's say both cars are cornering at 0.8g...

the downforce will only act downward...
you can't fight the gravity, but in this case

F1 car is weighing...
1600kg downward (car's weight+downforce)
480kg sideways (from cornering)

GT-R is weighing
1600kg downward (from car's weight)
1280kg sideways (from cornering)

so which one is more unstable?

I'm not a physics specialist so I know I might be wrong, but it's not that hard to understand this concept :rolleyes:

so idealy, the car should weigh as less as it can, and create as much downforce as it can.
you don't need any weight that is pulling you sideways.

[Mugen EvOlutioN]

ya it is weird


comparing GTR with F1
F1 has huge downforce to make up for the light weight thru cornering speed?

while GTR has less downforce so it uses heavy ass weight to give weight down the tires??


i dont think that really works, perhaps more of a bs theory to make up for his own design. If weight is so important than he wouldnt design SPEC V any lighter would he?


Look at lotus elise? its light as hell
Ferrari F360/F430 vs the CS version, both lighter by about 100kg to 120kg

Lambo gall. superleg edition is lighter as well...

so all in all? i call bullshit, no excuse for a 1750kg car

[hk20000]

Someone misses the point altogether here....

Let's say a Elise cup car with all its aerodynamics is faster than a GTR around Mission Raceway. 2 extremes here.

Then the GTR will work fine when it snows in January around the same track, in the snow, in the rain, and then go around to tow the Elise that's stuck in a snow bank.

That's the whole point of it. You don't drive a Elise cup car in the snow and you store it in the garage when it gets a bit damp. That's not acceptable for the GTR because it's marketing position is to make it work everywhere and at any speeds. Downforce cannot be made at street legal speeds. It's simple as that.

[SumAznGuy]

Downforce cannot be made at street legal speeds. It's simple as that.

That's not true. There is a trade off between low speed downforce and high speed drag or high speed downforce and next to zero low speed down force in terms of wings. Other things like splitters, and undercar areo are some of the newer advances that wind tunnel testing has helped prove effective. Of course, NASCAR is still years behind as they only recently started to use front end splitters.

[skyxx]

^ NASCAR is still years behind because they use Carburated engines. :lol

[Mugen EvOlutioN]

seriously who the FUCK watches NASTY car racing?


fucking go around in circles a million times circling like a fucking donut shop, where the hell is the fun in that?


lets see...how fast we can make a 30 degree left turn a million times and see who is the best woot woot and stay in 6th gear for 2 hrs

:rolleyes::rolleyes:


did i mention the car looks like ass?

[chunk_stir]

I don't think the $$ part comes into play at all for the GTR....it's supposed to be no bars held when that French guy was CEO he just wanted the halo car back.

The problem is that a GTR is not in the same market as a Pagani Zonda or Ferrari Enzo.... they serve different purposes, and therefore must be packaged differently.


$$$ ALWAYS come into play.... when they don't, you get something like the bugatti veyron. 50 units/year at $1.25 million/car with no anticipated payback until 6 yrs into the production run. Even with the veyron, it was an marketing exercise to resurrect the bugatti name so that they can sell other cars in the future for profit...

Few companies would produce a car with a blank cheque without a defined boundary. the GT-R is a car designed to compete with a 911 at 10's of thousands of dollars less at a production run of 12,000 globally @ $80,000 USD.

How they got there by choosing to go start with a heavy car and tune it well is what people are questioning now... but they did it and it works for the purposes they designed it for. That's pretty good engineering.

As Jeremy Clarkson put it:” They haven’t built a new car, they’ve built a new yard stick”.

[skyxx]

seriously who the FUCK watches NASTY car racing?


fucking go around in circles a million times circling like a fucking donut shop, where the hell is the fun in that?


lets see...how fast we can make a 30 degree left turn a million times and see who is the best woot woot and stay in 6th gear for 2 hrs

:rolleyes::rolleyes:


did i mention the car looks like ass?

The pits are pretty interesting to watch.

[illicitstylz]

I'm sure these guys that work on cars for the entireity of their life know what they're talking about
Posted via RS Mobile

[SumAznGuy]

The pits are pretty interesting to watch.

Actually, I felt the same way too, till someone pointed out that going 200+ mph in a circle is not an easy feat. One slight mistake, and you will lose speed and the guy behind you will whiz right by.

TV does slow down the action quite a bit.

[Mugen EvOlutioN]

^

every racing has its risks and death factor.

hence why its called RACING


compare to mountain togue, circuit racing, and ralley...that is seriously...nth

[Mugen EvOlutioN]

http://www.youtube.com/watch?v=7diiOZq8MJc&feature=related


thats racing

[skyxx]

Actually, I felt the same way too, till someone pointed out that going 200+ mph in a circle is not an easy feat. One slight mistake, and you will lose speed and the guy behind you will whiz right by.

TV does slow down the action quite a bit.

Yup, The inclines at Daytona are STEEP! The sport may look boring but when you actually drive one of the cars on the track you'll shit bricks. There are a few tracks in the NASCAR series that have left and right turns etc etc. I think one of them is the Gilles Villeneuve Track in Montreal.

[hk20000]

Yup, The inclines at Daytona are STEEP! The sport may look boring but when you actually drive one of the cars on the track you'll shit bricks. There are a few tracks in the NASCAR series that have left and right turns etc etc. I think one of them is the Gilles Villeneuve Track in Montreal.
Shit bricks because the bricks get pulled down in your guts by the G forces at the bank. :haha:

[Nightwalker]

I don't think the $$ part comes into play at all for the GTR....it's supposed to be no bars held when that French guy was CEO he just wanted the halo car back.

The low price tag is the only reason they're getting sold.

Spending big bucks on aerodynamics was probably going to be a bad return on investment, and it's a GT car anyway. It's meant to be as much of a comfortable daily driver that you can use year-round as it is for carving corners.

[trollguy]

who cares. ugly.

http://cache.gawker.com/assets/images/jalopnik/2009/10/NSX_GTR.jpg

[hk20000]

Spending big bucks on aerodynamics was probably going to be a bad return on investment, and it's a GT car anyway. It's meant to be as much of a comfortable daily driver that you can use year-round as it is for carving corners.
^ yeah and they certainly have a new market not tapped into before with this thing...

[carmaniac]

Here's what I think he's trying to say:

It's all on the basis of optimizing the contact patch of the tire for driving in dry/wet/snow for maximum stability.

Say for example there are 2 cars, they both have the same parameters, same engine, same tires and pressure, same weight distrubution, zero downforce. The only difference is the curb weight. Car A is the lighter car. Car B is the GT-R.

Car A will have less weight supported by the tires. What this creates is less of a contact patch for the tires on Car A. Contact patch = grip.

In a cornering situation, car A would have less overall grip and therefore be less stable. The benefits of lighter weight may be found in turn-in reaction, acceleration, braking, economy, etc...but it compromises overall grip (stability) in a steady-state situation.

For a professional driver which can react quickly, and knows what they're doing, the benefits of lightness outweigh stability in a corner since they can position and optimize weight distribution correctly to maximize grip from a given contact patch of the tire.

That contact patch for the GT-R was determined from the requirements of maximizing stability and control in all weather conditions. That is where the 1700kg and 485 hp comes from.

The Spec V is lighter because it in optimized for dry/wet conditions and not the snow.

Hope that makes sense...lol

[crazyazn]

If the GTR were lighter, there'd be a lot more accidents given the number of them owned by rich spoiled mainlanders/hongers.

[Timpo]

who cares. ugly.

http://cache.gawker.com/assets/images/jalopnik/2009/10/NSX_GTR.jpg

The GT-R looks quite nice in person.

[Mugen EvOlutioN]

Here's what I think he's trying to say:

It's all on the basis of optimizing the contact patch of the tire for driving in dry/wet/snow for maximum stability.

Say for example there are 2 cars, they both have the same parameters, same engine, same tires and pressure, same weight distrubution, zero downforce. The only difference is the curb weight. Car A is the lighter car. Car B is the GT-R.

Car A will have less weight supported by the tires. What this creates is less of a contact patch for the tires on Car A. Contact patch = grip.

In a cornering situation, car A would have less overall grip and therefore be less stable. The benefits of lighter weight may be found in turn-in reaction, acceleration, braking, economy, etc...but it compromises overall grip (stability) in a steady-state situation.

For a professional driver which can react quickly, and knows what they're doing, the benefits of lightness outweigh stability in a corner since they can position and optimize weight distribution correctly to maximize grip from a given contact patch of the tire.

That contact patch for the GT-R was determined from the requirements of maximizing stability and control in all weather conditions. That is where the 1700kg and 485 hp comes from.

The Spec V is lighter because it in optimized for dry/wet conditions and not the snow.

Hope that makes sense...lol


i guess that does explains better

:thumbsup:

[Prostrho]

I get to work really fast everyday cause Canada Line is heavy.

[hk20000]

It's extra heavy when loaded up with fat chicks.

[impactX]

I get to work really fast everyday cause Canada Line is heavy.

HAHAHA I lol'ed.

[impactX]

It's extra heavy when loaded up with fat chicks.

And fat chicks have bigger contact patches thus creating more grip.

[Jackygor]

And fat chicks have bigger contact patches thus creating more grip.

Makes sense, more grippin' for the pushin'...:haha:

[Ilagon]

The GT-R looks quite nice in person.

But still looks like shit compared to an 18 year old Honda.

[!e.lo_]

that's the best GT-R drawing EVAR!

didn't kno he was on the P10 Primera project... my mom drives one. lol

[ronald55555]

Here's what I think he's trying to say:

It's all on the basis of optimizing the contact patch of the tire for driving in dry/wet/snow for maximum stability.

Say for example there are 2 cars, they both have the same parameters, same engine, same tires and pressure, same weight distrubution, zero downforce. The only difference is the curb weight. Car A is the lighter car. Car B is the GT-R.

Car A will have less weight supported by the tires. What this creates is less of a contact patch for the tires on Car A. Contact patch = grip.

In a cornering situation, car A would have less overall grip and therefore be less stable. The benefits of lighter weight may be found in turn-in reaction, acceleration, braking, economy, etc...but it compromises overall grip (stability) in a steady-state situation.

For a professional driver which can react quickly, and knows what they're doing, the benefits of lightness outweigh stability in a corner since they can position and optimize weight distribution correctly to maximize grip from a given contact patch of the tire.

That contact patch for the GT-R was determined from the requirements of maximizing stability and control in all weather conditions. That is where the 1700kg and 485 hp comes from.

The Spec V is lighter because it in optimized for dry/wet conditions and not the snow.

Hope that makes sense...lol

That isn't necessarily true. Contact patch should not be parameter to optimize, but rather a variable to optimize centripetal force. Increasing the normal force on the tire will increase grip, however, increasing the normal force by increasing the mass is a backwards way to solve the problem. Grip does NOT increase linearly with increasing normal force(even with a larger contact area), that is the key concept to understand.
http://www.autozine.org/technical_school/handling/friction.jpg
The inertia however, WILL increase at a faster rate than grip with increasing mass.

The snow/wet handling argument is bs too. His whole argument is based on increasing contact area. Larger area = hydroplane. What he means is increasing contact pressure. There is a much better way than making the car heavier to increase contact pressure in snow. You can easily put smaller tires on a light car to increase the contact pressure. Here is a good example. Rally cars use very skinny tires in snow rallys. You dont see them using fat tires and making the car heavier.

http://www.autonewscast.com/wp-content/uploads/ford/hirvonennorway09.jpg

[dutch]

this.

finally someone i can agree with. What he's saying in the video is spin. It's a naturally heavy car and hes spinning it to seem like a good thing.

It's still a great car though.


ps. those rally cars on studded skinny snow tires get very similar grip to their dry road setup. The skinnyness of the tire is so that it can cut through the soft surface snow and get down to the harder surface underneath. And like ronald said, it increases the load at the contact patch. The studs also do a hell of a lot to increase the contact patch.

[ronald55555]

Here is a really simple way to put it:

By increase weight, you increase grip by X amount.
You also increase the inertia, and increase the grip necessary to create a sufficient centripetal force by amount Y.

Y is larger than X.

This is based on the laws of physics, and a very well known characteristic of modern day tires.

[Mugen EvOlutioN]

And fat chicks have bigger contact patches thus creating more grip.

sweet faster cornering speed!!! :thumbsup:


fuck his logic..just to cover his own flaws fatass design

1700kg is 1700kg no argument there

[hk20000]

GTR is large and it has presence. That's part of the marketing point too.

[ctsport]

It seems to me that the CE is just making excuses for the overweight GTR. We know this because every other manufacturer (except the Americans I guess lol) aim to do the complete opposite - to make the lightest sports cars possible. Lighter = better acceleration, braking, cornering and it doesn't have to compromise on daily driving either.

The GTR is a sports car, not a family sedan built for Alaska. The CE's excuse that GTR needs to be able to handle varied terrain applies to all the other cars in its class (Porche 911, Aston Martin Vantage, etc.) These cars are also mainly DDs and people who can afford these cars will most definitely have a Range Rover (or similar) if they live in areas with harsh winters. The GTR is a pig, albeit a nice one. So the real question is, what is the REAL REASON for all the extra weight? My guess is to keep costs down by using cheaper, heavier materials over lighter, more expensive materials.

[Death2Theft]

Well keep in mind the race cars subsitute weight with aero.
lighter is always better. the reason is when you go through a corner you have lateral load.

if you have a 2000 lb car vs a 3000 lb car with the same tire contact patch, the lighter car will corner faster because there is less weight in the lateral load.

his argument is that more weight is better in all conditions (dry, rain, snow), and of course he's trying to make it look good (its his baby).

I'm afraid all the gtr fan bois are going to think heavy cars are better.

the weight of the gtr is a side effect of the awd system. Anybody who preps are gtr for racing will strip it out to "add lightness".

[Mugen EvOlutioN]

It seems to me that the CE is just making excuses for the overweight GTR. We know this because every other manufacturer (except the Americans I guess lol) aim to do the complete opposite - to make the lightest sports cars possible. Lighter = better acceleration, braking, cornering and it doesn't have to compromise on daily driving either.

The GTR is a sports car, not a family sedan built for Alaska. The CE's excuse that GTR needs to be able to handle varied terrain applies to all the other cars in its class (Porche 911, Aston Martin Vantage, etc.) These cars are also mainly DDs and people who can afford these cars will most definitely have a Range Rover (or similar) if they live in areas with harsh winters. The GTR is a pig, albeit a nice one. So the real question is, what is the REAL REASON for all the extra weight? My guess is to keep costs down by using cheaper, heavier materials over lighter, more expensive materials.


my thoughts exactly


GTR is not a off road vehicle

[Elder_MMHS]

Interesting videos.

I'd like to see some real world comparison data between multiple cars, but part of me thinks the purpose, design, packaging - and as a side effect, the mass - of the vehicle is to minimize dynamic effects when driving near or at the limits. Static or near-static systems are much easier to engineer towards a given goal and ultimate easier to control as an end user.

[Marco911]

The engineer is full of shit in his explanation about why more weight is better. With the car's turbo and AWD system, they knew it was going to be a pig and didn't have the budget to use more exotic materials for weight redux.

[carmaniac]

That isn't necessarily true. Contact patch should not be parameter to optimize, but rather a variable to optimize centripetal force. Increasing the normal force on the tire will increase grip, however, increasing the normal force by increasing the mass is a backwards way to solve the problem. Grip does NOT increase linearly with increasing normal force(even with a larger contact area), that is the key concept to understand.
http://www.autozine.org/technical_school/handling/friction.jpg
The inertia however, WILL increase at a faster rate than grip with increasing mass.

The snow/wet handling argument is bs too. His whole argument is based on increasing contact area. Larger area = hydroplane. What he means is increasing contact pressure. There is a much better way than making the car heavier to increase contact pressure in snow. You can easily put smaller tires on a light car to increase the contact pressure. Here is a good example. Rally cars use very skinny tires in snow rallys. You dont see them using fat tires and making the car heavier.

http://www.autonewscast.com/wp-content/uploads/ford/hirvonennorway09.jpg

Agreed. Tire grip is not a linear quantity.

Contact pressure is what he meant not contact patch. I believe in one part of the video he implied the contact patch was a constant, ie the basis on a 20" wheel package. My bad.

The GT-R does have a system to maximize centripetal force through the use of its differentials shifting its inertia by way of power distribution through a corner.

I believe the explanation in the video is really only the very basic philosophy with the GT-R, be it the optimal philosophy or not is very much up for debate as we can see in this thread lol.

[Adrenaline Rush]

It seems to me that the CE is just making excuses for the overweight GTR. We know this because every other manufacturer (except the Americans I guess lol) aim to do the complete opposite - to make the lightest sports cars possible. Lighter = better acceleration, braking, cornering and it doesn't have to compromise on daily driving either.

The GTR is a sports car, not a family sedan built for Alaska. The CE's excuse that GTR needs to be able to handle varied terrain applies to all the other cars in its class (Porche 911, Aston Martin Vantage, etc.) These cars are also mainly DDs and people who can afford these cars will most definitely have a Range Rover (or similar) if they live in areas with harsh winters. The GTR is a pig, albeit a nice one. So the real question is, what is the REAL REASON for all the extra weight? My guess is to keep costs down by using cheaper, heavier materials over lighter, more expensive materials.

The GTR's weight isn't really that surprising. If you go by the past design of the GTR, you know it's going to start with AWD, twin turbos, and the ability to hold 4 people. In this day and age with all the safety regulations, airbags, crumple zones, etc, that's automatically mid to high 3000 lbs right there.

Even 15 years ago, the Dodge Stealth TT and the Mitsu 3000GT VR4 had very similar weight. With bigger wheels, brakes, 200 more hp, I'm sure Nissan had to use a lot of weight cutting measures to even make it's current weight. The current gen 911 Turbo is 3500 lbs and is over a foot shorter in wheelbase.

You could go lighter with carbon panels, carbon brakes, etc, but the price would skyrocket.

[hk20000]

Also he says he wants to cater to beginner drivers (lol he knows there are too many Vansky people out there)

so that weight transfer is "pre-done" or at least partially done so you can drive it super hamfistedly and come out feeling like a hero

hence everyone thinks it's like a PS3 game driving that thing. You just aren't so involved. Add a good dose of twin turbo horsepowers and it'll be fast regardless lol.

[LiquidTurbo]

Thanks for the vids. Nice to hear accurate theory from someone who's actually qualified to give it. Unlike 95% of RS.

[impactX]

Yes, deriving the GTR-R35 from Formula 1 is accurate as F1 has neither 480hp and 50-50 weight distribution nor does it intend to be driving on any snowy surface with 20" rims with summer tires.

What does it have to do with 20" anyway? The width and height of the tire have more to do with the size of the contact patch than the diameter of the rim.

[SumAznGuy]

Yes, deriving the GTR-R35 from Formula 1 is accurate as F1 has neither 480hp and 50-50 weight distribution nor does it intend to be driving on any snowy surface with 20" rims with summer tires.

What does it have to do with 20" anyway? The width and height of the tire have more to do with the size of the contact patch than the diameter of the rim.

Because 20" rims are more baller than 19's. =P

It's basically a weakass marketing ploy to make the fatass GTR look like god to all teh GTR fanbois.

[cressydrift]

If Nissan decided to make the GTR say 500kg lighter, every rich daddy kid and middle aged small cock man would write these things off. The SOB goes 300km/h for christ sakes. I am pretty sure the regulations required that these things added a few pounds. My only beef with the GTR is that it did not come in a stick version. It would not be as fast but I love sticks;)

http://www.youtube.com/watch?v=qrlM1Abbk5s

[billboa]

poodlr

[optiblue]

I want a car with a warp drive

[GabAlmighty]

And still ugly and huge as fuck.

[Chopstick]

man watching question 6 of the interview pissed me off

those 2 dickbirds were given the opportunity to meet and interview this guy, and what does the cameraman do? focus on that stupid fuck who does some retarded shit "ooh look at me, i can't understand a word he's saying, watch me try hard to roll my eyeballs which i can't cause my step dad hit me with his jaguar when i was 8".

u think mizuno woke up one day, grabbed his katana, grabbed a bottled ramune drink, got into his s15, drifted all the way up the touge with tofu in the back trunk, knocked on nissan's door, and asked: "ohioguzimus!! watashi wa mizuno kun. now make me fucking chief engineer, bitch"

no, he earned it

who the fuck was the guy in the brown shirt doing the interview? mizuno was a former racing engineer, team director, a man who's competed in group c, daytona, le mans, japan gt and f3000 when that douche was still in his skank hoe mother's womb, getting skullfucked by some huge black cock. when he says suck, you should fucking suck, and swallow it

kazutoshi mizuno isn't the emperor of japan, but he still demands respect. save the goofy "hey hey- - aaa booogaaaa lulululuuuuu *giggle* im fooling off in an interview! weee!" shit after the damm interview.

ya mizuno sucks at english, but at least his language doesnt make one sound like a total homo when they tell their friends they wanna have a smoke, go grab some fish & chips and have some sausages: "oi! lets get to the chippie in a jiffie for a fag? im feeling peckerish for bangers too mate!"

i hope next time he goes to japan he gets harassed by everyone that is able to drift, and drift circles around that bitch, all the way back to the airport

i am failing this post due to popular demand for proper internet grammar (-__-)....

[Chopstick]

holy shit i just wrote an essay

[jlai23]

nice post.... very interesting