Porsche 991 GT3

[DarkSunrise]

Originally Posted by Captain Snooze

The one thing that gets me a little is the father of the GTR , Kazutoshi Mizuno, maintains that more mass is advantageous.

Not sure I buy it. If more mass is advantageous, why would Nissan attempt to shed weight (66 lbs) with the Nismo version? Seems contradictory to me.

Originally Posted by ajc209

What mods did the car have? I see the massive wing, front lip and AP sprint. I assume slicks?

That's Ted Park's BRZ (ImperiousRex on this forum). There's a mod list at the end of the video, but here's the quick rundown:

- Greddy T518Z turbo
- JRZ RS coilovers
- AP Racing BBK
- 245/40/17 Dunlop Z2
- 17x9 RPF1
- APR front lip/canards
- Voltex Type 2 wing
- Robispec rad/oil cooler

You should check out his build page with current mods. Very well-built/sorted car:
http://www.ft86club.com/forums/showthread.php?t=28008

[bfrank1972]

Originally Posted by Captain Snooze

I have huge respect for the GTR. Its performance/price ratio puts a lot of European super cars to shame. (The fact that it has zero appeal to me is irrelevant.) The one thing that gets me a little is the father of the GTR , Kazutoshi Mizuno, maintains that more mass is advantageous. Now, I am just a forum punter. Mizuno-san is an engineering guru but I can't but help thinking that he is required to maintain this posture to give credence to the GTR's weight.
My thoughts:
1/ Higher mass make suspension tuning "easier"
2/ Mizuno-san says that high mass allows tyres to have better grip.
3/ By maintaining this posture?, charade? this point of view? there are no forum punters who have the credibility to dismiss Mizuno-san's claim.
4/ Maybe there is advantage to higher mass but it goes against all my criteria for a car.

Those are very good points- I've read about Mizuno's claims, and like you do not have the credentials at all to step up and explain or refute what he's saying, although there are some very knowledgable people on this forum that might be able to take a stab. My intuition tells me that less mass is always better than more. Yes increased downward force from weight increases traction at the tire contact patch, but you then have to overcome the greater lateral forces generated from transition of that greater mass. Greater force=more tire, suspension, chassis flex. More brake heat and wear. More tire wear and heat.

On and on, but you cannot deny what the GTR can do, and my intuition is based on my simplified view of the world maybe there is something to it, and why they didn't shave much off the Nismo. you have to applaud Nissan for their success in implementing unorthodox approaches, whether it be a street car or LMP.




Sent from my iPhone using Tapatalk

[CSG Mike]

Originally Posted by ajc209

See as much as I think you can be arrogant, at least you have the skills and expereience to back it up!
Thats a lap and a half. What mods did the car have? I see the massive wing, front lip and AP sprint. I assume slicks?

Voltex Type 2, APR lip, AP Sprint, RPF1 17x9 +45 with Dunlop Z2 245/40/17 (IIRC day 4.5?), Greddy turbo (225whp dynojet/265hp crank in that trim), JRZ RS

One of the tires was freshly patched because it had a nail causing it to leak air >.<

[CSG Mike]

Originally Posted by Captain Snooze

I have huge respect for the GTR. Its performance/price ratio puts a lot of European super cars to shame. (The fact that it has zero appeal to me is irrelevant.) The one thing that gets me a little is the father of the GTR , Kazutoshi Mizuno, maintains that more mass is advantageous. Now, I am just a forum punter. Mizuno-san is an engineering guru but I can't but help thinking that he is required to maintain this posture to give credence to the GTR's weight.
My thoughts:
1/ Higher mass make suspension tuning "easier"
2/ Mizuno-san says that high mass allows tyres to have better grip.
3/ By maintaining this posture?, charade? this point of view? there are no forum punters who have the credibility to dismiss Mizuno-san's claim.
4/ Maybe there is advantage to higher mass but it goes against all my criteria for a car.
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Substitute force for mass, and it'll make more sense. Aero is "virtual mass" that pushes down on the car as if you have more mass, without the penalties of having the extra mass.

[strat61caster]

Originally Posted by Captain Snooze

I have huge respect for the GTR. Its performance/price ratio puts a lot of European super cars to shame. (The fact that it has zero appeal to me is irrelevant.) The one thing that gets me a little is the father of the GTR , Kazutoshi Mizuno, maintains that more mass is advantageous. Now, I am just a forum punter. Mizuno-san is an engineering guru but I can't but help thinking that he is required to maintain this posture to give credence to the GTR's weight.
My thoughts:
1/ Higher mass make suspension tuning "easier"
2/ Mizuno-san says that high mass allows tyres to have better grip.
3/ By maintaining this posture?, charade? this point of view? there are no forum punters who have the credibility to dismiss Mizuno-san's claim.
4/ Maybe there is advantage to higher mass but it goes against all my criteria for a car.

Mass is stability, lots of engineering problems are solved by throwing more mass at it (structurally, controls, interns etc.)

I'm with you, personally I'll take less weight in a car any day, but the thought that 'all weight is bad' is foolish, especially around internet car enthusiasts who actually put their money where their mouth is. The hive mind mythos I am most certainly guilty of doesn't take into account all the variables. All you have to do is look at the current crop of hybrid super cars, they are porkers that weigh as much as muscle cars and yet have reset the bar for speed and handling. MT's drivers car of the year is an AMG over the GT4 and MX-5 because taking the mass 'penalty' for superior power, drivetrain, more robust suspension, and complex control systems absolutely does pay off, as it has for Nissan with the GTR. If Ferrari, Mclaren and Porsche thought they could go faster by shedding some of the electronics, slimming down the hybrid systems, and dropping the active suspensions, AWD, trick differentials etc., probably worth a hundred or two hundred lbs, they would have, those cars have no expense spared.

The current paragons of high performance mass production lightweight cars are Lotus and Alfa, their criticisms are well known, harsh busy ride characteristics (and potentially build quality) come with the package and limit the appeal.

[CSG Mike]

Originally Posted by strat61caster

Mass is stability, lots of engineering problems are solved by throwing more mass at it (structurally, controls, interns etc.)

I'm with you, personally I'll take less weight in a car any day, but the thought that 'all weight is bad' is foolish, especially around internet car enthusiasts who actually put their money where their mouth is. The hive mind mythos I am most certainly guilty of doesn't take into account all the variables. All you have to do is look at the current crop of hybrid super cars, they are porkers that weigh as much as muscle cars and yet have reset the bar for speed and handling. MT's drivers car of the year is an AMG over the GT4 and MX-5 because taking the mass 'penalty' for superior power, drivetrain, more robust suspension, and complex control systems absolutely does pay off, as it has for Nissan with the GTR. If Ferrari, Mclaren and Porsche thought they could go faster by shedding some of the electronics, slimming down the hybrid systems, and dropping the active suspensions, AWD, trick differentials etc., probably worth a hundred or two hundred lbs, they would have, those cars have no expense spared.

The current paragons of high performance mass production lightweight cars are Lotus and Alfa, their criticisms are well known, harsh busy ride characteristics (and potentially build quality) come with the package and limit the appeal.

Poking around the chassis of modern cars yields a lot of strange harmonic balancers...

[bfrank1972]

Originally Posted by strat61caster

Mass is stability, lots of engineering problems are solved by throwing more mass at it (structurally, controls, interns etc.)

I'm with you, personally I'll take less weight in a car any day, but the thought that 'all weight is bad' is foolish, especially around internet car enthusiasts who actually put their money where their mouth is. The hive mind mythos I am most certainly guilty of doesn't take into account all the variables. All you have to do is look at the current crop of hybrid super cars, they are porkers that weigh as much as muscle cars and yet have reset the bar for speed and handling. MT's drivers car of the year is an AMG over the GT4 and MX-5 because taking the mass 'penalty' for superior power, drivetrain, more robust suspension, and complex control systems absolutely does pay off, as it has for Nissan with the GTR. If Ferrari, Mclaren and Porsche thought they could go faster by shedding some of the electronics, slimming down the hybrid systems, and dropping the active suspensions, AWD, trick differentials etc., probably worth a hundred or two hundred lbs, they would have, those cars have no expense spared.

The current paragons of high performance mass production lightweight cars are Lotus and Alfa, their criticisms are well known, harsh busy ride characteristics (and potentially build quality) come with the package and limit the appeal.

Just keep in mind that the 'light' cars you're comparing to the 'heavy' cars are a fraction of the price. The AMG GT is over $170,000. Technology (expensive) is certainly the dominant factor in these cars - I would find it interesting to see a car with much of this tech built into a relatively lighter weight 'race' version.

[strat61caster]

Originally Posted by bfrank1972

Just keep in mind that the 'light' cars you're comparing to the 'heavy' cars are a fraction of the price. The AMG GT is over $170,000. Technology (expensive) is certainly the dominant factor in these cars.

I'm not sure what you're getting at... My counterpoint however is the C63 AMG that took 4th in MT's most recent test.

Starting at $72k, (tested at $91k) it can swing at a Cayman S or 4C (or Exige) for nearly even money with two extra doors and boasting a 4.0s 0-60 (vs 4.6s & 4.5s respectively) and a Laguna lap of 1:40 vs the Cayman's 1:41 or 4c's 1:43 ('13 and '14 best driver tests respectively with Pobst behind the wheel, respective as tested prices at $101k and $69k).

The AMG weighs in at ~3,900 lbs to the Cayman's ~3,000 and 4C's ~2,400.

The point is that there no such thing as a free lunch and not all mass is evil.

Say, isn't this a 911 thread?

[Captain Snooze]

Originally Posted by strat61caster

Say, isn't this a 911 thread?

[bfrank1972]

You referenced the AMG GT as MT's best driver's car, that's a $170K car.

My point is these cars are heavier (and that is a disadvantage) but all the expensive tech in these cars make up the difference and then some. Add power to the Cayman or 4C and they would surpass the C63 AMG. Add some of the fancy new engineering Mercedes threw into the AMG GT and a lighter car would benefit (as long as the tech isn't adding a ton of weight).

Anyway that's my point - I need somebody to specifically explain to me how added weight is advantageous, and I'm definitely open to hear theories. Until then, I will continue to believe that if you subtract 500 lbs from a GTR or AMG GT, it will be much faster around a track.

Not sure how this topic diverged, I just remember responding to people talking about the GTR.

Originally Posted by strat61caster

I'm not sure what you're getting at... My counterpoint however is the C63 AMG that took 4th in MT's most recent test.

Starting at $72k, (tested at $91k) it can swing at a Cayman S or 4C (or Exige) for nearly even money with two extra doors and boasting a 4.0s 0-60 (vs 4.6s & 4.5s respectively) and a Laguna lap of 1:40 vs the Cayman's 1:41 or 4c's 1:43 ('13 and '14 best driver tests respectively with Pobst behind the wheel, respective as tested prices at $101k and $69k).

The AMG weighs in at ~3,900 lbs to the Cayman's ~3,000 and 4C's ~2,400.

The point is that there no such thing as a free lunch and not all mass is evil.

Say, isn't this a 911 thread?

[strat61caster]

Originally Posted by bfrank1972

Anyway that's my point - I need somebody to specifically explain to me how added weight is advantageous, and I'm definitely open to hear theories. Until then, I will continue to believe that if you subtract 500 lbs from a GTR or AMG GT, it will be much faster around a track.

Nobody is going to be able to break the laws of physics, F=ma.

Yes, if you subtract 500 lbs it will be faster, assuming everything is re-engineered around the lighter weight. Just like adding 200hp to a 4C will make it faster, assuming everything is re-engineered around the added power (and weight) and so does adding stickier tires to just about everything.

It's been explained, there is no free lunch and the compromises taken on the GT-R with regards to added weight allow the car to perform insanely well at a price point. That was the point of my comments. If the engineer in that video was given a button to press that magically took 100lbs out of the GT-R penalty free he would have pressed it in a heartbeat, re-tuned the suspension, possibly recalibrated the gizmos and the revised car would be for sale within a year. He'd probably break the button if it was 500 lbs by hitting it so hard.

If you want to see 'what cars can do' you look at the 918, P1, and LaFerrari or you look at Le Mans Prototypes.

Aaah benchracing at it's finest.

[bfrank1972]

Originally Posted by strat61caster

Nobody is going to be able to break the laws of physics, F=ma.

Yes, if you subtract 500 lbs it will be faster, assuming everything is re-engineered around the lighter weight. Just like adding 200hp to a 4C will make it faster, assuming everything is re-engineered around the added power (and weight) and so does adding stickier tires to just about everything.

It's been explained, there is no free lunch and the compromises taken on the GT-R with regards to added weight allow the car to perform insanely well at a price point. That was the point of my comments. If the engineer in that video was given a button to press that magically took 100lbs out of the GT-R penalty free he would have pressed it in a heartbeat, re-tuned the suspension, possibly recalibrated the gizmos and the revised car would be for sale within a year. He'd probably break the button if it was 500 lbs by hitting it so hard.

If you want to see 'what cars can do' you look at the 918, P1, and LaFerrari or you look at Le Mans Prototypes.

Aaah benchracing at it's finest.

If you read back a bit, we were talking about Mizuno and claims the GTR has better performance due to its greater weight. Just looking for some educated insight to support that claim vs. the more obvious things you were referring to. I like to keep an open mind as I certainly don't "know it all" (some people think they do). Thanks for your input though

[strat61caster]

Originally Posted by bfrank1972

If you read back a bit, we were talking about Mizuno and claims the GTR has better performance due to its greater weight. Just looking for some educated insight to support that claim vs. the more obvious things you were referring to. I like to keep an open mind as I certainly don't "know it all" (some people think they do). Thanks for your input though

Direct quote from video at ~0:59
"I understand. Lighter weight is better, all people say, BUT!" and he goes on to extoll the virtues of downforce and equates that to mechanical grip of a road car.

I don't think he is claiming that weight adds performance to the GT-R as you seem to have interpreted it, but rather that the weight of their design choices does have a benefit to absolute grip, stability, and driver control.

[humdizzle]

Originally Posted by CSG Mike

That's a very GTR owner statement of you, with which I always rebuttle: I don't care what lap times a car turns with someone else at the wheel; I care what lap times an owner turns in their own car. You can only crush people's hopes and dreams if you actually can run that time yourself. Saying that XYZ driver did ABC lap time at a track doesn't change the result of a gutted civic dusting a GTR at the canyon...

Bench racing only results in internet arguments.


Why not drive the Viper/Z06/whatever other car as much as the GTR? I agree that the GTR is way, way easier to drive for the average person, but the weight is a huge killer...

pretty much the last statement. Its relatively easy to go fast in a GTR. The car does what I tell it.. no drama. I can adjust the tcs and be comfortable that it will never step out on me. rain or shine. even in freezing temps on mpss tires i have no worries driving it hard on a lower boost setting

Also I dont track. There isn't one near me. Most of my fun time is on highways and backroads. As a street car the GTR shines even more in that respect. You and adjust throttle/brake/gear mid turn with no drama.

Its probably the most accessible 600whp street car I can have short of a 650s or 911 turbo S