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no actually my distant cousins are john and john quincy adams on my mothers side. my fathers side came over on the mayflower. i am as blue-blooded a wasp as you will ever find.
i care about my country and get very upset when i see the uneducated masses of america making poor decisions based on selfish merit. we are turning into a nation of afraid and obese anti-intellectuals. and the more we distance ourselves from the rest of the world, the less allies were gonna have when we actually need help - cuz that day is coming.
the numbers of people that hate us is growing. like all those homeless and parentless 12 year olds in iraq, that didnt give two ****s about america in 2002, now have somewhere to direct their hate. THOSE are the terrorists of tomorrow the people willing to die by flying a plane into a building......and weve made them....
Heavy as balls? Yes. But if I were Cadillac, this is exactly the car I would build.
The big players in this sector are BMW, Mercedes, and Audi. If you wanted to play in that league with virtually no history making sports sedans, but you had access to the LSx parts catalog, what would you do? Would you try to compete with BMW's chassis design and handling? Would you try to match Audi's technophilia? Hell no. You'd go right for AMG's nuts with the biggest, baddest, ballsiest freight train of a car possible.
wow that is a great list of parts for a great looking car. and the 4000lbs is a est. but still i wouldnt care.
but why one eart do they keep comparing it to the m5 when it is a c63/m3/rs4/is-f competitor
Well with the 550lb ft of TQ I would imagine it's in the same class as the M5 now, i mean seriously I can't see an M3 really being in the same class as this car now. Same argument for the C63 and IS-F....
The RS4...eh, i've always thought that the S4 should be compared to the M3, not the RS4 but then again there's the S6 so that slot is already filled.
The interior is teh sex.
4000lbs huh? If so we're close to having to stop at weigh stations.
depending on how that MRC is calibrated you might not be able to feel it in the twisties, i know as heck you sure wont feel it in the peddle with that LS3 in there....
depending on how that MRC is calibrated you might not be able to feel it in the twisties, i know as heck you sure wont feel it in the peddle with that LS3 in there....
Crazy. just crazy. A car that powerful would be useless to me here in NY. I'd still love to have it anyway.
Well with the 550lb ft of TQ I would imagine it's in the same class as the M5 now, i mean seriously I can't see an M3 really being in the same class as this car now. Same argument for the C63 and IS-F....
The power isn't as important as the size of the car and the way it goes about what it does.
I get the impression that this CTS-V is probably going to be much more of a rocket than a jet fighter. If that's true, it would definitely be more like an M5 than an M3.
Quote:
Originally Posted by alicious
The RS4...eh, i've always thought that the S4 should be compared to the M3, not the RS4 but then again there's the S6 so that slot is already filled.
The previous generation S4 was definitely a decent car to compare with the previous M3. The new M3 just stepped things up in a few ways, so now the RS4 is a better comparison.
Quote:
Originally Posted by alicious
depending on how that MRC is calibrated you might not be able to feel it in the twisties, i know as heck you sure wont feel it in the peddle with that LS3 in there....
You can never totally hide weight. Even with the most brilliant suspension and chassis tuning, the car will still feel muted and just that little bit lazy.
Also, if they do manage to make it turn and feel like it's a few hundred pounds lighter, it'll be with super stiff springs that make the ride firm and super soft tires that wear out quickly.
Also, if they do manage to make it turn and feel like it's a few hundred pounds lighter, it'll be with super stiff springs that make the ride firm and super soft tires that wear out quickly.
Isn't that what the magna-hydraulic-electric shocks are for?
Not quite sure why stiff springs are the only way to make a car "feel" a few hundred lbs lighter. If MRC isn't designed for performance handling, I wonder why it's being used in the new ultra high performance ZR-1?
Quote:
GM has carried its Magnetic Ride Control (MRC) suspension system over to the CTS-V. The technology — which also appears in the new Corvette ZR1 — uses shocks controlled by electro-magnets, rather than mechanical valves. This makes MRC the world’s fastest-reacting suspension technology, according to GM.
Electronic sensors at all four wheels “read the road” every millisecond, making constant adjustments to damping to create a smooth ride when appropriate, and a firm ride when required. The technology prevents body roll during hard corners, yet keeps passengers comfortable while cruising.
Not quite sure why stiff springs are the only way to make a car "feel" a few hundred lbs lighter. If MRC isn't designed for performance handling, I wonder why it's being used in the new ultra high performance ZR-1?
I was just sourcing what you posted, beat me to it.
alicious, the dampers will help a great deal, but they are not a magic wand.
Don't forget that firmness in magneto-rheological dampers comes from the effective viscosity of the fluid in the damper bodies: higher viscosity for more firmness, lower viscosity for less firmness. Higher viscosity means the fluid flows more slowly through the openings in the body of the damper, which is how the damper resists lean. But the flow doesn't totally stop (because that would be stupid), so the suspension will still slowly compress the longer it's leaned on, especially when the car is heavy. Also, that extra firmness does not cause any spring effect whatsoever, so it can't make the suspension return to its original position on its own after hitting a bump. On top of that, no matter how firm the dampers get to keep the car flat in a corner, they will still have to soften momentarily every time there is a small bump or the car will lose traction, and that will permit lean.
By contrast, firm springs can resist lean forever and return the suspension to its original position after a bump. It's a "dumb" solution but it has its advantages.
So, long story short: Magneto-rheological dampers are a great way to provide a little extra body control in transitions without compromising ride quality, but they can't fully take the place of higher spring rates. That's why the car will still need firm springs. Less firm than it would need without those trick dampers, maybe, but still firm.
Theory /= real life. In reality, the amount if time the shock would have to resist one particular motion is nominal.
Stiff springs will also make the car more jumpy when the road surfaces get uneven. A car with softer springs but adjustable shocks will be much better in keeping the car on the road.
Again, the ultra high performance Corvette ZR-1 will feature this technology. I don't think anyone needs to question the viability of this system to a performance application. Especially when weight is a big issue with the Vette. They won't want to add any unnecessary weight if it's function can't be jusitfied.
Well with the 550lb ft of TQ I would imagine it's in the same class as the M5 now, i mean seriously I can't see an M3 really being in the same class as this car now. Same argument for the C63 and IS-F....
The RS4...eh, i've always thought that the S4 should be compared to the M3, not the RS4 but then again there's the S6 so that slot is already filled.
the cts is int he same class as a c class/m3/a4 etc so i fail to understand why the hot rod version isnt in that class. not everyone needs a car that will carve corners like a surgon. this car will be what many people would like their daily driver to be like.
Quote:
Originally Posted by d00df00d
alicious, the dampers will help a great deal, but they are not a magic wand.
Don't forget that firmness in magneto-rheological dampers comes from the effective viscosity of the fluid in the damper bodies: higher viscosity for more firmness, lower viscosity for less firmness. Higher viscosity means the fluid flows more slowly through the openings in the body of the damper, which is how the damper resists lean. But the flow doesn't totally stop (because that would be stupid), so the suspension will still slowly compress the longer it's leaned on, especially when the car is heavy. Also, that extra firmness does not cause any spring effect whatsoever, so it can't make the suspension return to its original position on its own after hitting a bump. On top of that, no matter how firm the dampers get to keep the car flat in a corner, they will still have to soften momentarily every time there is a small bump or the car will lose traction, and that will permit lean.
By contrast, firm springs can resist lean forever and return the suspension to its original position after a bump. It's a "dumb" solution but it has its advantages.
So, long story short: Magneto-rheological dampers are a great way to provide a little extra body control in transitions without compromising ride quality, but they can't fully take the place of higher spring rates. That's why the car will still need firm springs. Less firm than it would need without those trick dampers, maybe, but still firm.
i think you might be a bit lost on how this actually works. if i recall it works just liek a normal shock but it has an oil/fluid in it that has metal particles suspended in it. when the car needs a more stiff shock a current is sent through the fluid and the metal becomes magnetic and clumps together. this will trump any advantage gained by simple stiffer spring rates since these work at the instant that they are needed and their input is forever variable.
i think you might be a bit lost on how this actually works. if i recall it works just liek a normal shock but it has an oil/fluid in it that has metal particles suspended in it. when the car needs a more stiff shock a current is sent through the fluid and the metal becomes magnetic and clumps together. this will trump any advantage gained by simple stiffer spring rates since these work at the instant that they are needed and their input is forever variable.
I know how it works.
I'm just saying it doesn't "trump" stiff springs because it doesn't do the same thing. It may be a super trick damper, and it may do a better job than any other damper widely available, but it's still a damper. It's made to work with the springs.
Maybe I overdramatized the need for stiff springs with what I initially said, but the fact is that you can't just slap 100 lb/in springs into a 4,000 lb sport sedan with bling wheels and huge brakes just because you have magneto-rheological dampers. They can resist lean to an extent, and they can permit suspension movement when needed, but they provide no propulsive force to put the suspension back to where it was after it's been deflected. A spring has to provide that force. With a lot of sprung and unsprung mass, that spring has to be firm or it won't overcome the suspension's inertia fast enough.
What's cool about a magneto-rheological damper is that it can "get out of the way" by softening momentarily, and then prevent oscillation and other unwanted motion by stiffening at the right time. It can also do cool things like exerting high compression damping force to resist lean in a corner, and then exerting very little force until the very end of the rebound stroke to let the spring return the suspension to where it was as quickly as possible after the exit. It facilitates and controls, like a commander in a squad of soldiers. But, like a commander, it's not always the main "doer" in the equation.
You can never totally hide weight. Even with the most brilliant suspension and chassis tuning, the car will still feel muted and just that little bit lazy.
You forgot to mention a super-duper trick AWD system....
__________________
Tuning a car isn't a crime, but spelling it "tunning" ought to be. - ....
GM has carried its Magnetic Ride Control (MRC) suspension system over to the CTS-V. The technology — which also appears in the new Corvette ZR1 — uses shocks controlled by electro-magnets, rather than mechanical valves. This makes MRC the world’s fastest-reacting suspension technology, according to GM.
Electronic sensors at all four wheels “read the road” every millisecond, making constant adjustments to damping to create a smooth ride when appropriate, and a firm ride when required. The technology prevents body roll during hard corners, yet keeps passengers comfortable while cruising
I'm just saying it doesn't "trump" stiff springs because it doesn't do the same thing. It may be a super trick damper, and it may do a better job than any other damper widely available, but it's still a damper. It's made to work with the springs.
Maybe I overdramatized the need for stiff springs with what I initially said, but the fact is that you can't just slap 100 lb/in springs into a 4,000 lb sport sedan with bling wheels and huge brakes just because you have magneto-rheological dampers. They can resist lean to an extent, and they can permit suspension movement when needed, but they provide no propulsive force to put the suspension back to where it was after it's been deflected. A spring has to provide that force. With a lot of sprung and unsprung mass, that spring has to be firm or it won't overcome the suspension's inertia fast enough.
What's cool about a magneto-rheological damper is that it can "get out of the way" by softening momentarily, and then prevent oscillation and other unwanted motion by stiffening at the right time. It can also do cool things like exerting high compression damping force to resist lean in a corner, and then exerting very little force until the very end of the rebound stroke to let the spring return the suspension to where it was as quickly as possible after the exit. It facilitates and controls, like a commander in a squad of soldiers. But, like a commander, it's not always the main "doer" in the equation.
Is that clearer?
mag ride will allow enough body roll to fully compress the spring and it can also stiffen to a point where the spring is never compressed. it has the ability to turn the entire mass of fluid into a solid block of metal depending on the amount of current sent through it. the cars springs in this case are there just to ensure the car can carry a load of cargo/people. the springs are usless since the mag ride will more or less keep the car from ever needing to rely upon the spring during handling.
its like having a soft shock/spring and a brick all at the same time depending on the current sent though it.
liqid. you have a link that confirms how much the mag ride can actually solidify the shock fluid? I didn't see it when I was digging. It would completely destroy the basis of his theory
mag ride will allow enough body roll to fully compress the spring and it can also stiffen to a point where the spring is never compressed. it has the ability to turn the entire mass of fluid into a solid block of metal depending on the amount of current sent through it. the cars springs in this case are there just to ensure the car can carry a load of cargo/people. the springs are usless since the mag ride will more or less keep the car from ever needing to rely upon the spring during handling.
its like having a soft shock/spring and a brick all at the same time depending on the current sent though it.
You don't want a brick at any point. Zero compliance means zero traction and will break things real fast.
And again, springs are nowhere near useless because the dampers do nothing to return the suspension to its resting position after it deflects.
Think about how a suspension works. It compresses and extends, right? The idea is that it's supposed to compress when you hit a bump and then extend afterward so that the wheel stays on the ground at all times. Rebound is also important after a corner because there will always be some lean, and you need the car to settle before the next corner.
We all know how well these dampers can resist motion when necessary and permit motion when necessary. But they can't cause motion. If you had these dampers with no springs, the car would ride lower and lower every time you hit a bump or took a hard corner until it was riding on the bumpstops.
If you had these dampers with soft springs, the car would still take too long to settle between maneuvers and traction would be compromised in some situations because the springs wouldn't be able to exert enough force to overcome the inertia of the chassis and the suspension to keep the wheel in contact with the ground.
You still need springs with rates appropriate for the unsprung and sprung mass of the car, and the goals you are trying to achieve.
So would overly stiff springs that you are advocating. But there's a big diff. Spring rates can't be changed.(you can use non-linear springs because those are soft and then stiff, thus not supporting your theory) But shock stiffness can. It can go from full stiff to full soft in milliseconds. So, on compression, it can be very stiff. Once on the rebound cycle, it can go soft (to allow the spring to extend).
So again, this seems to be a much better solution than just using overly stiff springs that will skitter you into the weeds when the road gets uneven.
Plus there's no reason why the mag ecu can't anticipate what to do based on speed, steering wheel position, yaw rate and such. Thus, it could actually respond before an event happens.
Quote:
Originally Posted by d00df00d
You don't want a brick at any point. Zero compliance means zero traction and will break things real fast.
And again, springs are nowhere near useless because the dampers do nothing to return the suspension to its resting position after it deflects.
Think about how a suspension works. It compresses and extends, right? The idea is that it's supposed to compress when you hit a bump and then extend afterward so that the wheel stays on the ground at all times. Rebound is also important after a corner because there will always be some lean, and you need the car to settle before the next corner.
We all know how well these dampers can resist motion when necessary and permit motion when necessary. But they can't cause motion. If you had these dampers with no springs, the car would ride lower and lower every time you hit a bump or took a hard corner until it was riding on the bumpstops.
If you had these dampers with soft springs, the car would still take too long to settle between maneuvers and traction would be compromised in some situations because the springs wouldn't be able to exert enough force to overcome the inertia of the chassis and the suspension to keep the wheel in contact with the ground.
You still need springs with rates appropriate for the unsprung and sprung mass of the car, and the goals you are trying to achieve.
From an aftermarket magnashock maker. I assume the same can be applied to this oem application also.
Quote:
The additional damping (from turning on the “M-R”) is nearly constant at any piston velocity. However, the ratio between highest & lowest possible damping force is usually 10:1 or better at low piston speeds (around 1 in/sec).
Any damping force in between these two lines (the GREY areas) is instantly available in a MagneShock.
This additional damping can be a function of ANY variable, calculation or sensor signal.
The actual damping is infinitely adjustable in between these two limits. Note that a MagneShock can develop significant damping at ZERO velocity.
This means it can be “locked-up” - NO motion will occur until this large force, applied to the damper, is exceeded.
liqid. you have a link that confirms how much the mag ride can actually solidify the shock fluid? I didn't see it when I was digging. It would completely destroy the basis of his theory
i got it in a mag from gm back when the c5 came out...i'll check in a bit online or ask if the chassis engineer here has any info on it.
Can it reset the suspension after compression though?
I hate to regurgitate d00df00d's words but dampers, no matter how sophisticated, can only alter suspension motion imparted by either the vehicles mass, road imperfection, body roll/dive/squat, etc. It can't CAUSE any motion on its own though. That's the point.
__________________
Tuning a car isn't a crime, but spelling it "tunning" ought to be. - ....
He has a point. It doesn't matter how soft the shock becomes on rebound. The vehicles mass still needs to be overcome by the spring.
The only point of contention was the fact that liqid said "a car doesn't need springs". Hardly worth the discussion for such an abstract discussion.
The subject of the discussion is whether this technology is favorable to overly stiff shocks (I say overly because that's the extreme it would take to match the performance potential of this tech).
Which would you rather have? Overly stiff springs and the required overly stiff non-adjust or manualy adjust shocks that have to go with it?
Or med/stiff springs that will allow a very good ride coupled with infininately adjustable/ultra fast responding electronicly controlled shocks that allow cars like the ZR-1 perform with the best the world has to offer?
What's the point? So what? A spring cannot detect any of the car's motions either.
In fact this damper system CAN detect these motions and not only that, can reasonably predict such motions. And they can work together as a system of 4 vs 4 independant springs that know nothing of each other's motions.
Quote:
Originally Posted by nismology
Can it reset the suspension after compression though?
I hate to regurgitate d00df00d's words but dampers, no matter how sophisticated, can only alter suspension motion imparted by either the vehicles mass, road imperfection, body roll/dive/squat, etc. It can't CAUSE any motion on its own though. That's the point.
What's the point? So what? A spring cannot detect any of the car's motions either.
In fact this damper system CAN detect these motions and not only that, can reasonably predict such motions. And they can work together as a system of 4 vs 4 independant springs that know nothing of each other's motions.
Who said anything about detection? After suspension compression, the only thing that can extend it again is spring pressure. Dampers (no matter how sophisticated) are ultimately only as good as the spring rates they are couple to. It's not a complete replacement for appropriately stiff springs.
__________________
Tuning a car isn't a crime, but spelling it "tunning" ought to be. - ....
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