Light weight cars for amateurs says GTR test driver
12-04-2012 | 06:36 AM
#16
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As far as I have heard, the electronics on the R35 just won't do their magic if the car is not brutally thrown into corners, which suggests to me that they may be got to work more effectively the higher the weight of the car.
I think it would take a certain level of selflessness for a professional driver to adopt anti-instinctive habits to extract the most of this car. This is probably what this driver meant but obviously was not careful enough when he chose his words!
I think it would take a certain level of selflessness for a professional driver to adopt anti-instinctive habits to extract the most of this car. This is probably what this driver meant but obviously was not careful enough when he chose his words!
also comparing it to the Bugatti Veron and the 997 911 turbo in acceleration times.
12-04-2012 | 07:15 AM
#18
I think I watched the same program as you, where i'm from 'handling' often refers to the way the car feels as much as how fast it corners, with regards what the driver said I call BS too, lighter cars are faster and feel better to me but then it doesn't say nissan on my shirt ha ha.
To defend the gtr for just a minute, it did hold the nurburgring production car lap record for a while, one which it took from the 911 turbo, they also had to design new tires for the gtr because conventional tires pealed off the rims. so you cant really suggest that a large heavy car can't corner either but remove its spare seats, bose stereo, navigation etc and you know it would be faster!!
To defend the gtr for just a minute, it did hold the nurburgring production car lap record for a while, one which it took from the 911 turbo, they also had to design new tires for the gtr because conventional tires pealed off the rims. so you cant really suggest that a large heavy car can't corner either but remove its spare seats, bose stereo, navigation etc and you know it would be faster!!
12-04-2012 | 08:29 PM
#20
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I caught up on one at the track. Check out the video at the 5:40 min mark for the goDZirra! The driver cooks a turn at 6:05 and the electronics save the car at 6:07:
https://www.youtube.com/watch?v=lNGo...&feature=g-upl
https://www.youtube.com/watch?v=lNGo...&feature=g-upl
12-05-2012 | 12:49 AM
#21
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I caught up on one at the track. Check out the video at the 5:40 min mark for the goDZirra! The driver cooks a turn at 6:05 and the electronics save the car at 6:07:
https://www.youtube.com/watch?v=lNGo...&feature=g-upl
https://www.youtube.com/watch?v=lNGo...&feature=g-upl
It's almost funny watching from behind how the car moves all over the place but doesn't quite spin. But it does slow down.... a LOT.
A GTR will never be be a real race car due to its weight (at least not a production based GTR).
TonyG
12-05-2012 | 01:01 AM
#22
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Very familiar situation. It's pretty easy to push the GTR to the point that they over heat the tires. When that happens... no amount of electronics will save them. I've done this to quite a few running R6's.
It's almost funny watching from behind how the car moves all over the place but doesn't quite spin. But it does slow down.... a LOT.
A GTR will never be be a real race car due to its weight (at least not a production based GTR).
TonyG
It's almost funny watching from behind how the car moves all over the place but doesn't quite spin. But it does slow down.... a LOT.
A GTR will never be be a real race car due to its weight (at least not a production based GTR).
TonyG
If you'd put that GTR driver from the video into another car with RWD, he wouldn't last the race, in fact i doubt he'd finish the race with the car in 1 piece.
12-05-2012 | 01:11 AM
#23
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Very familiar situation. It's pretty easy to push the GTR to the point that they over heat the tires. When that happens... no amount of electronics will save them. I've done this to quite a few running R6's.
It's almost funny watching from behind how the car moves all over the place but doesn't quite spin. But it does slow down.... a LOT.
A GTR will never be be a real race car due to its weight (at least not a production based GTR).
TonyG
It's almost funny watching from behind how the car moves all over the place but doesn't quite spin. But it does slow down.... a LOT.
A GTR will never be be a real race car due to its weight (at least not a production based GTR).
TonyG
initially here in Texas many would only last 3-5 laps before temps would shut down the tranny and lose the brakes. It seems they have either upgraded the factory components some and perhaps gone aftermarket. Until they drop serious weight from that platform it will never be able to turn anything more than a few fast parade laps
12-05-2012 | 01:16 AM
#24
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"the GTR weighs around 1800kgs, which the weight helps it handle like it does, only amateurs say light weight cars are better" Well the first part of that statement is true. It's weight is what makes it handle the way it does. But if it were lighter, it would handle better. So I guess he is half....right...hahahaha
12-05-2012 | 01:45 AM
#25
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Hey... it's a great car. Make no mistake. It's just too heavy to be anything more than a fun car....(unless you throw $100k at it.... or more).
I've seen pro GTR's at the track. and they have a TON of money thrown at them. Still... they are way to heavy. You can engineer out the heat problems... but you can't engineer out the weight problems. And that's too bad because it's got a great drive train and electronics set.
TonyG
I've seen pro GTR's at the track. and they have a TON of money thrown at them. Still... they are way to heavy. You can engineer out the heat problems... but you can't engineer out the weight problems. And that's too bad because it's got a great drive train and electronics set.
TonyG
12-05-2012 | 06:57 PM
#26
Three Wheelin'
It was total BS.
Light weight always wins, all other thing being equal.
Take a GT based class of racing where you have to have 10 lbs per hp for example. You can have a car that weights 1000lbs with 100HP or you have have a car that weighs 5000lbs with 500HP. Which one will be faster? The lighter one.
Why?
Because the heavier one has more mass to slow down at the end of the straight, so apples-to-apples, it will not brake as good. Also, more mass to slow down means reaching the limits of adhesion of the tire at a lower rate of deceleration. The light car wins.
Also, going around a corner..... the heavier car has more mass. This it generates more centrifugal force, apples-to-apples, at the same speed... which will result in the tire reaching it's limit of lateral adhesion (when it starts to slide) at a slower speed than the light car. The light car wins again.
The heavier car also generates more body movement, more nose dive than the lighter car.
The heavier car, while it has more power, has more mass to accelerate. So while the two cars have the same lb/hp and though theoretically accelerate the same, they do not in the case of coming out of a tight corner. This because, again, apples-to-apples, to accelerate the heavier car at the same rate as the lighter car, the heavier car needs to apply 5x more TQ the tire than does the lighter car, while also generating more centrifugal force in the corner.. so the driving tire is loaded on both axis a LOT more than that of the lighter car which will result in earlier wheel spin.
Not to mention that apples-to-apples... the heavier car will over heat the tires faster than the tires lighter car.
on and on......
Bottom line.... weight beats HP on the track, all other things being equal.
And yes... I understand that you have more weight to push down on the tire which means more grip. Still... the lighter car wins.
TonyG
Light weight always wins, all other thing being equal.
Take a GT based class of racing where you have to have 10 lbs per hp for example. You can have a car that weights 1000lbs with 100HP or you have have a car that weighs 5000lbs with 500HP. Which one will be faster? The lighter one.
Why?
Because the heavier one has more mass to slow down at the end of the straight, so apples-to-apples, it will not brake as good. Also, more mass to slow down means reaching the limits of adhesion of the tire at a lower rate of deceleration. The light car wins.
Also, going around a corner..... the heavier car has more mass. This it generates more centrifugal force, apples-to-apples, at the same speed... which will result in the tire reaching it's limit of lateral adhesion (when it starts to slide) at a slower speed than the light car. The light car wins again.
The heavier car also generates more body movement, more nose dive than the lighter car.
The heavier car, while it has more power, has more mass to accelerate. So while the two cars have the same lb/hp and though theoretically accelerate the same, they do not in the case of coming out of a tight corner. This because, again, apples-to-apples, to accelerate the heavier car at the same rate as the lighter car, the heavier car needs to apply 5x more TQ the tire than does the lighter car, while also generating more centrifugal force in the corner.. so the driving tire is loaded on both axis a LOT more than that of the lighter car which will result in earlier wheel spin.
Not to mention that apples-to-apples... the heavier car will over heat the tires faster than the tires lighter car.
on and on......
Bottom line.... weight beats HP on the track, all other things being equal.
And yes... I understand that you have more weight to push down on the tire which means more grip. Still... the lighter car wins.
TonyG
A bit more theory:
If you look at a graph of side force versus vertical load (for a given slip angle) you will see that the slope of the line decreases as load increases.
So the best ratio of side force to vertical load is at small amounts of vertical load.
Also (because the curve is convex instead of concave) the total side force available at the AVERAGE tyre loading will always be *more* than the sum of the side forces at the individual tyre loadings.
(EDIT: replaced "less" with "*more*", whoops!)
So, any attempt to
a) keep the average tyre loadings as low as possible, and
b) reduce the spread of the tyre loadings
will improve the ratio of vertical load to side force, which will improve the cornering acceleration.
Generally the approaches are to:
1) reduce the height of the centre of gravity
2) reduce the overall weight
(won't discuss aero here)
Even if you consider that the optimum slip angle for a tyre tends to increase as vertical load increases, it is still not enough to overcome the reduction in force ratio due to the increased vertical load.
(otherwise, sway bars wouldn't work as expected)
Now, if the graph was conVEX instead of conCAVE, the opposite would be true: we would want LOTS of weight transfer, high CG, and more weight. In other words, we would all run out and buy SUV's. Oh, wait...
Cheers,
Mike
Last edited by mikey_audiogeek; 12-05-2012 at 09:47 PM. Reason: *more* (was "less", whoops!)
12-05-2012 | 07:03 PM
#27
Three Wheelin'
12-05-2012 | 07:54 PM
#28
I stopped putting faith in anything a Japanese auto journalist said after about the 10th super car review by Best Motoring where the NSX won every comparison.
I have a few friends who are big into Japanese cars and even they agree that they are pretty heavily biased when it comes to reviews.
I have a few friends who are big into Japanese cars and even they agree that they are pretty heavily biased when it comes to reviews.
12-05-2012 | 11:16 PM
#29
Rennlist Junkie Forever
Actually I'm buying a 2013 Porsche Panamera Twin Turbo V6 for the car for installation next summer. Stock... 420HP. And you know another 100HP is just a ***** twist away.....
TonyG
