The PDCC "might increase understeer" reference
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Three Wheelin'
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The PDCC "might increase understeer" reference
Other than a couple of magazine reviews _theorizing_ that PDCC somehow would increase understeer, I remain confused as to why this would be? Why would reducing roll and maintaining suspension geometry increase understeer? Would a car with stiffer static rollbars understeer more than one with softer rollbars, all else being equal?
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Other than a couple of magazine reviews _theorizing_ that PDCC somehow would increase understeer, I remain confused as to why this would be? Why would reducing roll and maintaining suspension geometry increase understeer? Would a car with stiffer static rollbars understeer more than one with softer rollbars, all else being equal?
Now picture entire books -- at the graduate level of engineering -- on this subject, and the practicing engineers sneaking out to sacrifice a free-range chicken by the light of a full moon before penning a new suspension.
That is how complex this subject is.
Stick with "to many drivers, it feels like a PDCC car has increased understeer" and you're safe. Don't try to defend an argument that understeer really is being increased or is not. Just trust me on this.
If you paid me enough, I'd find out quickly by instrumenting two comparable cars with and without PDCC. And the answer wouldn't matter to anyone but my banker. What really matters is lap times in racing (they improve) and the feel to drivers (they disagree).
Drive one for yourself and see how you like it. Best answer anyone can provide. Unless of course you'd like to contact my banker.
Gary
Still plays with cars.
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I drove a PDCC car on track and found that the handling was less predictable, my guess is that the roll bars stiffened up mid corner. On the road this would not be noticeable, in fact I didn't feel it other than the fact that the car rode well but had no body lean. On the track .. I think it would take some getting used to, since the added roll stiffness changed the cornering attitude unexpectedly. I read that there is a software update which improves the situation. The car I drove was an early model and did not have any updates.
As a general rule, some body roll adds grip to the outside tires, and in racing we try and use the least amount of roll stiffness. It's a trade off between grip in fast corners and stability in fast transitions like "esses" where additional stiffness is a benefit.
As a general rule, some body roll adds grip to the outside tires, and in racing we try and use the least amount of roll stiffness. It's a trade off between grip in fast corners and stability in fast transitions like "esses" where additional stiffness is a benefit.
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Yes. In front. Stiff ones in back increase oversteer. PDCC is not like stiff rollbars though.
Now picture entire books -- at the graduate level of engineering -- on this subject, and the practicing engineers sneaking out to sacrifice a free-range chicken by the light of a full moon before penning a new suspension.
That is how complex this subject is.
Stick with "to many drivers, it feels like a PDCC car has increased understeer" and you're safe. Don't try to defend an argument that understeer really is being increased or is not. Just trust me on this.
If you paid me enough, I'd find out quickly by instrumenting two comparable cars with and without PDCC. And the answer wouldn't matter to anyone but my banker. What really matters is lap times in racing (they improve) and the feel to drivers (they disagree).
Drive one for yourself and see how you like it. Best answer anyone can provide. Unless of course you'd like to contact my banker.
Gary
Now picture entire books -- at the graduate level of engineering -- on this subject, and the practicing engineers sneaking out to sacrifice a free-range chicken by the light of a full moon before penning a new suspension.
That is how complex this subject is.
Stick with "to many drivers, it feels like a PDCC car has increased understeer" and you're safe. Don't try to defend an argument that understeer really is being increased or is not. Just trust me on this.
If you paid me enough, I'd find out quickly by instrumenting two comparable cars with and without PDCC. And the answer wouldn't matter to anyone but my banker. What really matters is lap times in racing (they improve) and the feel to drivers (they disagree).
Drive one for yourself and see how you like it. Best answer anyone can provide. Unless of course you'd like to contact my banker.
Gary
This is a very good response.
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Thread Starter
Three Wheelin'
Joined: Feb 2012
Posts: 1,458
Likes: 233
From: SF Bay Area
Thx guys. If one has faith in that the Herr Professor Doktors at Porsche would map the software correctly for all this, then -- theoretically -- they could hit the sweet spot for all of the above.
