The REAL reason for C8 understeer
10-21-2019, 01:36 PM
#21
Nearly all mass production street cars understeer. No reason to expect the Corvette to be different. It is safer.
When an untrained driver gets a car out of sorts, their natural reaction is to get off the gas and jam the brakes. It is not just the American public, it is the public in general. With an understeering car, that is exactly what you would do to right the situation, with an oversteering car, that can exacerbate the situation immensely. As Warp Factor also mentioned, the understeer builds up, and gives the operator plenty of warning. Oversteer doesn't. All in all, it is the smart decision. As mentioned in another thread, for those who have the knowledge on what they are doing to be changing the characteristics of their car, the solution is generally available and easy to do. If I can make a FWD car spin out with nothing but some air pressure and a $130 sway bar, it shouldn't be too hard to loosen up a Corvette.
When an untrained driver gets a car out of sorts, their natural reaction is to get off the gas and jam the brakes. It is not just the American public, it is the public in general. With an understeering car, that is exactly what you would do to right the situation, with an oversteering car, that can exacerbate the situation immensely. As Warp Factor also mentioned, the understeer builds up, and gives the operator plenty of warning. Oversteer doesn't. All in all, it is the smart decision. As mentioned in another thread, for those who have the knowledge on what they are doing to be changing the characteristics of their car, the solution is generally available and easy to do. If I can make a FWD car spin out with nothing but some air pressure and a $130 sway bar, it shouldn't be too hard to loosen up a Corvette.
Last edited by wvanepps; 10-21-2019 at 01:38 PM.
10-21-2019, 01:38 PM
#22
Not sure I agree. The C7 Z06 with 650 HP going to the wheels can be tamed by the traction control PTM system and you can still have fun with it. I have never had a problem with it even in track mode. Now if I fully disable traction control then it is super easy to lose control. Would be interesting to know if the C8 still has crazy understeer with PTM turned on in track mode. I would never even think of turning off traction control in any modern day sports car except for maybe a BRZ / FRS as I don't have the skill for it.
10-21-2019, 01:47 PM
#23
I think the OP is dead on.
These guys know damn well how to engineer a car to behave how they want it to - especially when they have a blank slate to start from.
The car is turning exactly like they planned for it to.
The guys buying these cars for the race track are likely going to be satisfied be a very differently configured and tuned Z06.
These guys know damn well how to engineer a car to behave how they want it to - especially when they have a blank slate to start from.
The car is turning exactly like they planned for it to.
The guys buying these cars for the race track are likely going to be satisfied be a very differently configured and tuned Z06.
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10-21-2019, 02:21 PM
#25
Drifting
I think the OP is dead on.
These guys know damn well how to engineer a car to behave how they want it to - especially when they have a blank slate to start from.
The car is turning exactly like they planned for it to.
The guys buying these cars for the race track are likely going to be satisfied be a very differently configured and tuned Z06.
These guys know damn well how to engineer a car to behave how they want it to - especially when they have a blank slate to start from.
The car is turning exactly like they planned for it to.
The guys buying these cars for the race track are likely going to be satisfied be a very differently configured and tuned Z06.
GM has some VERY capable chassis engineers and development managers (i.e. Alex McDonald). I'm sure they worked very hard at making the C8 the best handling vehicle for the range of customers who will be buying it.
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10-21-2019, 02:44 PM
#26
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Not sure I agree. The C7 Z06 with 650 HP going to the wheels can be tamed by the traction control PTM system and you can still have fun with it. I have never had a problem with it even in track mode. Now if I fully disable traction control then it is super easy to lose control. Would be interesting to know if the C8 still has crazy understeer with PTM turned on in track mode. I would never even think of turning off traction control in any modern day sports car except for maybe a BRZ / FRS as I don't have the skill for it.
10-21-2019, 02:44 PM
#27
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It's the American public. Now before I get labeled as a fanboy, or some other attempt at claiming I'm wrong, please read this in full. GM has been driving, testing , and developing this car for YEARS.
They are also the same people that have tuned the chassis of the C7 to the level it is, so it's obvious they know how to tune a chassis. The C8 is a whole new architecture and so, other then the spelling
of the name, it really is a new design (for Corvette). GM also knows they are going to attract buyers, some that have never owned a sports car, much less a Corvette. They have WAY too much at stake to allow
the car to be labeled as dangerous. Bear with me, so Mr. 50 something who is finally in the position to have a toy sees the new Corvette and pulls the trigger. He comes out of a Ford Explorer that has a
center of gravity similar to a stack of cigar boxes. He is out in his new whiz bang Corvette and he is amazed he can double the posted speed of the off ramp without even a tire squeal. The cars
performance potential seems limitless. One day he takes his favorite posted 40 mph ramp at 98 mph and goes off road, at that speed it's ugly. When interviewed, he says he has no idea what went
wrong, one second I was on the ramp and the next I was flying off the road. Not a real driver, but people listen. His friends say they have been with him many times in the Explorer and he is a responsible
driver, must be the car. Today not many Americans can take responsibility for their actions, everything HAS to be someone else's fault. The idiot that dumps hot coffee in his lap BLAMES McDonalds for
serving him hot coffee. The reason the C7 can be tuned as neutral as it is, is because there are tens thousands of FE Corvettes that haven't been wadded up for GM to point to. Some idiot crashes C7
he is viewed as the problem, with the C8 they have zero cars to point to that haven't been wadded. Because they are selling to the masses, I don't think GM has a choice in the matter, they just have
TOO MUCH to lose.
They are also the same people that have tuned the chassis of the C7 to the level it is, so it's obvious they know how to tune a chassis. The C8 is a whole new architecture and so, other then the spelling
of the name, it really is a new design (for Corvette). GM also knows they are going to attract buyers, some that have never owned a sports car, much less a Corvette. They have WAY too much at stake to allow
the car to be labeled as dangerous. Bear with me, so Mr. 50 something who is finally in the position to have a toy sees the new Corvette and pulls the trigger. He comes out of a Ford Explorer that has a
center of gravity similar to a stack of cigar boxes. He is out in his new whiz bang Corvette and he is amazed he can double the posted speed of the off ramp without even a tire squeal. The cars
performance potential seems limitless. One day he takes his favorite posted 40 mph ramp at 98 mph and goes off road, at that speed it's ugly. When interviewed, he says he has no idea what went
wrong, one second I was on the ramp and the next I was flying off the road. Not a real driver, but people listen. His friends say they have been with him many times in the Explorer and he is a responsible
driver, must be the car. Today not many Americans can take responsibility for their actions, everything HAS to be someone else's fault. The idiot that dumps hot coffee in his lap BLAMES McDonalds for
serving him hot coffee. The reason the C7 can be tuned as neutral as it is, is because there are tens thousands of FE Corvettes that haven't been wadded up for GM to point to. Some idiot crashes C7
he is viewed as the problem, with the C8 they have zero cars to point to that haven't been wadded. Because they are selling to the masses, I don't think GM has a choice in the matter, they just have
TOO MUCH to lose.
10-21-2019, 02:46 PM
#28
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Easier to read a long post. Now I see what you are saying, on my computer screen at work it's just double spaced single lines. Now that I'm home mine is doubled too and looks odd. Sorry about that.
Last edited by Phil1098; 10-21-2019 at 08:15 PM.
10-21-2019, 03:48 PM
#29
10-21-2019, 07:42 PM
#30
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10-22-2019, 12:24 AM
#31
So there has to be some consideration toward track surface conditions as opposed to street surfaces, it is impossible to have a car that handles properly on all track surfaces, let alone build a car that handles perfectly on the street and all track surfaces all with one single setup.... if you have a loose track with lower traction you need a softer setup to compensate, softer setup induces weight transfer easier... on a grippier surface you need a tighter setup as you have enough grip that you can induce transfer even against a tighter suspension... now if you try to have a too soft setup on a grippy track you end up with unpredictable handling, the suspension will store up energy then unload in a unpredictable manner. ie grinding understeer and snap oversteer comes to mind.. a properly setup car will not go from traction to traction loss unpredictably, it will always transition smoothly and predictably. obviously a more complex topic then I can describe in a couple sentences but moral of the story setup is not voodoo and if your in any way even remotely serious about taking your C8 to the track you should be be more then willing and able to play with some setups and tire combinations to get the car to handle the way you want, to me it sounds like the C8 is factory tuned a little more towards street surfaces then it is for track surfaces which makes sense to me... most C8's will be driven on lower traction street surfaces so the suspension is likely tuned to compensate and perform properly in those conditions ..
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10-22-2019, 01:49 AM
#33
Obviously GM wanted this car to be a killer in everything. I don't think they engineered on purpose under steer into the car, that makes no sense in what they said that the FE platform was maxed out. They built this car to be better than the model before on the track. If they were building cars just for road use they would have stopped with the C5 performance. You really don't need more than that for the road.
I think people are just making up excuses and not taking it for what it really is.
Why is it so hard for people to say we stuffed up, or we did not get it absolutely right. Never happens these days, always an excuse blah blah blah.
10-22-2019, 04:27 AM
#34
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Obviously GM wanted this car to be a killer in everything. I don't think they engineered on purpose under steer into the car, that makes no sense in what they said that the FE platform was maxed out. They built this car to be better than the model before on the track. If they were building cars just for road use they would have stopped with the C5 performance. You really don't need more than that for the road.
I think people are just making up excuses and not taking it for what it really is.
I think people are just making up excuses and not taking it for what it really is.
Find a 90 degree intersection with no traffic. Take some average car, and make a right turn (in the US) a little faster each time, with throttle and brakes neutral. (The reason for the turning right is so you have room to run wide). A point will come where the front starts to plow, scrubbing off speed. Go a little faster, and the front will scrub off more speed, and start to run wide. Go faster yet, and you just get more of the same. It's very progressive and controllable, and doesn't require any special skills, like instantly countersteering to keep from looping the car and losing control completely.
That's what's safest for your average driver, and why it is the default setup on most cars.
Once GM's attorneys have enough consumer experience to be satisfied that the C8 won't self-destruct in the hands of the average driver, perhaps they'll allow the car to go in the direction of a more neutral setup. That's just one of the consequences of our extremely litigious society.
Last edited by Warp Factor; 10-22-2019 at 04:40 AM.
10-22-2019, 05:06 AM
#35
I don't think so. It is such common knowledge that over/understeer can be altered with something as simple as changing the front/rear swaybar stiffness ratios, that it's inconceivable that GM doesn't know this as well.
Find a 90 degree intersection with no traffic. Take some average car, and make a right turn (in the US) a little faster each time, with throttle and brakes neutral. (The reason for the turning right is so you have room to run wide). A point will come where the front starts to plow, scrubbing off speed. Go a little faster, and the front will scrub off more speed, and start to run wide. Go faster yet, and you just get more of the same. It's very progressive and controllable, and doesn't require any special skills, like instantly countersteering to keep from looping the car and losing control completely.
That's what's safest for your average driver, and why it is the default setup on most cars.
Once GM's attorneys have enough consumer experience to be satisfied that the C8 won't self-destruct in the hands of the average driver, perhaps they'll allow the car to go in the direction of a more neutral setup. That's just one of the consequences of our extremely litigious society.
Find a 90 degree intersection with no traffic. Take some average car, and make a right turn (in the US) a little faster each time, with throttle and brakes neutral. (The reason for the turning right is so you have room to run wide). A point will come where the front starts to plow, scrubbing off speed. Go a little faster, and the front will scrub off more speed, and start to run wide. Go faster yet, and you just get more of the same. It's very progressive and controllable, and doesn't require any special skills, like instantly countersteering to keep from looping the car and losing control completely.
That's what's safest for your average driver, and why it is the default setup on most cars.
Once GM's attorneys have enough consumer experience to be satisfied that the C8 won't self-destruct in the hands of the average driver, perhaps they'll allow the car to go in the direction of a more neutral setup. That's just one of the consequences of our extremely litigious society.
Might have to return my C6Z because it does not have enough under steer built into it to make it safe for the road.
10-22-2019, 05:33 AM
#36
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By the sounds of it this C8 has more under steer than the previous gen. So GM was putting out unsafe cars up till now? Why has there not been litigation if the cars did not have this much under steer built into them?
Might have to return my C6Z because it does not have enough under steer built into it to make it safe for the road.
Might have to return my C6Z because it does not have enough under steer built into it to make it safe for the road.
I think GM is being more and more careful all the time. Remember the ignition switch fiasco?
In my experience, a rear-mid engine car is more difficult to recover when the back starts to slide out, if one isn't practiced at it.
I didn't own a C6, but the C7Z's I drove at Spring Mountain would understeer at the limit, giving me safe feedback before I got into bigger trouble. Sure, the back end would come out if too much power was applied.
Last edited by Warp Factor; 10-22-2019 at 05:41 AM.
10-22-2019, 05:51 AM
#37
Le Mans Master
The REAL reason for C8 under-steers --- I question your conclusions going up the ramp at 98 MPH and dumping the Car rather it Under-steers or Over-steers you still dump the Car ??
10-22-2019, 06:05 AM
#38
Lets get serious, if you are being stupid and reckless you will lose the car irrespective if it is a FE, ME or a beetle or a ferrari.
10-22-2019, 06:32 AM
#39
Race Director
I think the OP is dead on.
These guys know damn well how to engineer a car to behave how they want it to - especially when they have a blank slate to start from.
The car is turning exactly like they planned for it to.
The guys buying these cars for the race track are likely going to be satisfied be a very differently configured and tuned Z06.
These guys know damn well how to engineer a car to behave how they want it to - especially when they have a blank slate to start from.
The car is turning exactly like they planned for it to.
The guys buying these cars for the race track are likely going to be satisfied be a very differently configured and tuned Z06.
The ME is the BETTER car for handling by a professional driver AT THE LIMIT which all of us are not... it is for all intent and purposes an "easier" car to manipulate around a road course better than the FE car... but for those approaching amateur/moderate race car driver status? that trait is gonna sting vs what they're used to. Just my opinion... and over time both the driver and the engineers will dial it in better. OR in C9 it will be fixed with different wheelbase suspension set up programming whatever.
That comment about "they're working on it" makes me believe they will re cal both electronics and geometry a bit if not for this car? than the GS Z06 etc.
And maybe a new model year adjustment with some newly designed suspension components should it not be cost prohibitive.
Last edited by 23/C8Z; 10-22-2019 at 06:35 AM.
10-22-2019, 07:10 AM
#40
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