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Old 02-12-2008, 05:23 AM   #31
Moppie
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Re: Whats the point of Front Wheel drive?

Quote:
Originally Posted by Nereth
None - this is based purely on engineering theory. That way you can cut the subjective stuff out, and you can cut the outliers out.

And that maybe your problem.
Is it the engineering that is letting the idea of FWD performance down, or our failure to reconcile your understanding of the engineering with our real world experiance?


As has been said several times, there are a variety of very quick, very fun to drive, FWD performance cars. Made by companies with an understanding of automotive engineering that far away exceeds the knowledge of anyone on this forum.



Try and look at it a different way.
Motor bikes go very quickly on two wheels.
If you watch a fully race prepped FWD, driven properly on a circuit, they tend to do the same thing. It's just the wheels are laid out differently, and there are an extra set hanging out the back that stop it tipping over backwards under acceleration.
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Old 02-12-2008, 05:52 AM   #32
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Re: Whats the point of Front Wheel drive?

Quote:
Originally Posted by Moppie
And that maybe your problem.
Is it the engineering that is letting the idea of FWD performance down, or our failure to reconcile your understanding of the engineering with our real world experiance?
I don't know what you are saying, but keep in mind you generally can't trust real world experience for such a broad thing - there are too many variables. The reason you like a FWD car more than a RWD car may not be because it is FWD, but because, for example, it is more responsive or has a firm-feeling ride. To compare such a basic part of a car, you have to break the car down to very basic principles, and in real life, comparing say a camaro to a corolla, absolutely everything has changed. It's impossible.


Quote:
Originally Posted by Moppie
As has been said several times, there are a variety of very quick, very fun to drive, FWD performance cars. Made by companies with an understanding of automotive engineering that far away exceeds the knowledge of anyone on this forum.
And there are a variety of very fun RWD cars. They are not fun because they are FWD, they are fun for a whole multitude of reasons. You have to seperate 'FWD' out from all the other parameters involved.



Quote:
Originally Posted by Moppie
Try and look at it a different way.
Motor bikes go very quickly on two wheels.
If you watch a fully race prepped FWD, driven properly on a circuit, they tend to do the same thing. It's just the wheels are laid out differently, and there are an extra set hanging out the back that stop it tipping over backwards under acceleration.
...that is a really poor analogy and I doubt you need me to explain why.


I have had a similar discussion on another board. Fortunately, I had the good sense to just quote out of a reliable book rather than try to explain the things myself. I'm going to quote myself from that forum right now:

Quote:
Originally Posted by Nereth
Heres a lot of points from Race Car Vehicle Dynamics, by Milliken and Milliken. Mostly quoted, somewhat edited (square brackets) if its long and winding/unclear:


plagiarizing

[FWD:]

1)
FWD has been most successful [compared to FWD performance in other areas] in the lower power/weight range and in situations where superior directional stability on low [coefficient of friction tracks] is important. There has never been a successful front-drive Grand Prix car nor a competitive Indianapolis car of more than 300hp.

2) In straight-line acceleration, the load on the front wheels is reduced by the longitudinal load transfer. This leads to the use of forward static weight bias to control higher powered, lighter vehicles and may require 60-70% (or more) of the static weight on the front wheels. A limited slip differential may be desirable to control the lightly loaded wheel under combined cornering/acceleration (turn exit) but this may induce undesirable steering forces and generally interfere with control feedback to the driver. Some success is now found with the viscous type limited slip

3) Forward weight bias with tractive effort on the front tends to induce excessive understeer in the linear range, plow at the limit (in steady-state), and reduce max lateral. This is due to tire load sensitivity [coefficient of friction on pneumatic tires reduces with load] and friction circle effects and is most noticeable on acceleration out of turns. The understeer/plow may be reduced by stickier tires on the front and by taking some of the lateral load transfer on the rear [stiffen roll hardness on rear]. The amount of [lateral load transfer taken by] the rear is limited by lift of the inside rear wheel.

4) The forward weight bias is basically unfavorable to maximum braking because of tire load sensitivity losses due to unequal front and rear loading. The situation is improved if larger tires are used on front. Proportionally more rear brake (or even lockup of the rear tires) is one technique which has been used to get the tail out for promoting "turn-in" and rear slip angle for cornering. It has been used in various forms such as the so-called "hand-brake turn" (popular in rallying) and "trail braking" where the left foot is used for braking and the right foot remains on the throttle to keep the front wheels from locking up.

5) Trim [ ie. heading] changes occur frequently in circuit racing, for example, if balked by another competitor in a turn. Dropped throttle transfers load forward, increases the inward lateral force on the front wheels, and increases the [grip available] on front. [The car turns into the corner to an extent] dependent on the amount of engine motoring torque (note that with an automatic transmission, motoring torque at the wheels may be very small). If the vehicle is stable it will retrim without control action at a higher lateral acceleration. If near the limit it may spin out if not caught by control action. As Reid Railton pointed out, when a front drive is loose and near incipient spin the best treatment may be to ease on the throttle and transfer load aft, but "the relief is only temporary." Driving a high powered front drive at the limit requires more judgment and experience, as the Novi history demonstrates.

In summary, it is more difficult to achieve a neutral vehicle over the operating range with front-wheel drive than with rear- or four-wheel drive. The compromises required to achieve a balance of handling and performance over a circuit are critical. The situation becomes progressively more difficult as power is increased.

/plagiarizing

I feel kind of guilty to have copied all that, but its less than 10% (By a lot) so I think it's legal. Anyway, as thanks to the Millikens, I hereby recommend you all go out and buy yourself a copy, as there is much more to read than that.
The text in question is very well known amongst automotive engineers, something of an industry standard. And if you are interested in the subject, I do think it's worth buying, but it's not particularly cheap.
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Old 02-12-2008, 08:37 AM   #33
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Re: Whats the point of Front Wheel drive?

Quote:
Originally Posted by GreyGoose006
ok...
I issue you a challenge.

find me a car for 500 dollars that has a 5 speed manual transmission,
performance suspension,
can run 12 second quarters (ive never tried, but i hear from the previous owner)
has EITHER a targa top or T-tops,
is fuel injected,
has 6month insurance premiums in the $275 range,
can 90% of the replacement parts for it at autozone, that day
and comes WITHOUT all the automated systems that are so "convieneint" to drivers today...
i hate automatic lights, seatbelt dingers, lane change warning systems, ect...
I know this isn't directed at me, but here's your answer. 1989 Dodge Daytona Turbo II.

Can be found for around $500, has a five speed Getrag, and has a very good suspension for the time.
Can run 12s reliably for very cheap.
Can be found with t-tops.
Port fuel injection.
I'm not sure of insurance, but it should be in the same range.
You can find replacement parts anywhere.
No automated crap
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Old 02-12-2008, 08:56 AM   #34
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Re: Whats the point of Front Wheel drive?

Quote:
Originally Posted by Polygon
I know this isn't directed at me, but here's your answer. 1989 Dodge Daytona Turbo II.

Can be found for around $500, has a five speed Getrag, and has a very good suspension for the time.
Can run 12s reliably for very cheap.
Can be found with t-tops.
Port fuel injection.
I'm not sure of insurance, but it should be in the same range.
You can find replacement parts anywhere.
No automated crap
ding ding ding
we have a winner.

and guess what?
i actually really wanted one of those before i got my camaro
it was as simple as, i couldnt find one.

also, body build-quality is an issue too.
my camaro is rust free


whats funny is that from the right angles, they even look pretty similar
the daytona even has the "camaro" rear taillight triangles...
(if you havent noticed, when viewed from the side, the rear tailights form a triangle-esque shape
http://www.moparautos.com/images/84day2.jpg
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Old 02-12-2008, 01:44 PM   #35
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Re: Whats the point of Front Wheel drive?

Quote:
Originally Posted by Nereth
There are ways to get the car to drift or oversteer even if it understeers stock - as you know, rear roll hardness, or more optimal suspension geometry, etc. But these things have compromises involved. For example, a sway bar links the wheels in question and throws off bump handling. Also, it's entirely possible to sacrifice drive traction for lateral traction by moving the COG backwards.
If you're claiming that sway bars are a bad thing, then you'd have some serious arguments with anyone who designs or tunes suspension.

The drive traction you are soo concerned about is only an issue in two situations. One is traffic light racing, the other is the 1/4 mile drags. In all forms of racing other than stupid straight lines it is not an issue.

Quote:
Originally Posted by Nereth
None - this is based purely on engineering theory. That way you can cut the subjective stuff out, and you can cut the outliers out.
You should have mentioned that earlier.
See the problem with your theory is that it hasn't been tested. The outlier at this stage is your lack of knowledge about the very vehicles you're discussing.

Quote:
Originally Posted by Nereth
During braking, the front loads up and the rear unloads. lets say at 1 G 20% of the load moves forward. If you start with 60:40, in a FF car, you will wind up with 80:20. If you have an RR car, starting at 40:60, you wind up with 60:40. The loadings are more even the more weight is towards the back.
How about instead of throwing around numbers you picked out of thin air, actually delivering real numbers.
Like the stopping distance of a mazda 3 (fwd) vs an RX8 (rwd).

Oh look at that, the mazda 3 stops better in the wet.
http://www.rx8.co.nz/Reviews/pr_brake_2904.aspx

Take a look here and you'll see many fwd cars pulling up faster than the rx8 too.
http://www.movit.de/rahmen/stoptbl.htm
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Old 02-12-2008, 04:24 PM   #36
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Re: Whats the point of Front Wheel drive?

Quote:
Originally Posted by Moppie
You are as arrogant as you are ignorant, its a dangerous combination.

When you have some real experiance, can provide some useful and real world advice, then you might be in a position to question others on their choice of car.
In the mean time, as far as you are concerned, the Camaro is a very good car.
It sold in very large numbers, and there are thousands of owners who are very passionate about it.
I bet you have never even driven one.

It puts you in about the same class as the 15 year old kids who make assumptions about cars based on the car magazines their daddy brings home.
aaah but it is you who are over arrogant and if you think im ignorant, you are guilty of it worse. how else, without ignorance, can you claim i have no real world experience? i dont remember telling you my life story. i commented on my opinion of his car. if you think my opinion isnt valid you are more ignorant than i could ever be. sure the camaro sold in large numbers, and lots of people like it. so did such gems as the fiero, sunbird, taurus, pontiac 6000, and many others i could name. it doesnt make them good cars. theres a reason that auto manufacturers cheap out whenever they can on cars. sure there were versions of camaros that were better than other camaros, but GM among other companies, is guilty of using a bad cost cutting strategy of trying to make crappy platforms perform well enough to sell a sports car version. just because it can get from one stoplight to another faster than a buick doesnt mean its better. im sorry but straight line speed doesnt do much for me if it cant turn.

Quote:
Originally Posted by GreyGoose006
ding ding ding
we have a winner.

and guess what?
i actually really wanted one of those before i got my camaro
it was as simple as, i couldnt find one.

also, body build-quality is an issue too.
my camaro is rust free


whats funny is that from the right angles, they even look pretty similar
the daytona even has the "camaro" rear taillight triangles...
(if you havent noticed, when viewed from the side, the rear tailights form a triangle-esque shape
http://www.moparautos.com/images/84day2.jpg

uh huh i guess i see your point even though your camaro isnt 500 bucks anymore, and when it was, didnt run anywhere close to 12s. another car that fits your model? a foxbody crustang(wait, no ttops. why is this a big deal?). or a mkIII turbo supra, or a z31 turbo 300zx, or a swapped rx7, or a turbo 240sx(wait no ttops again. just me but ttops isnt all that.), how about such make believe cars as a volvo 240 wagon with a 5 liter bmw v12 in it? irocs get bad gas mileage, handle like shit, dont look good in my opinion, and have technology straight out of 1971(except for the fuel injection). theres cars that can do things your camaro never could. have you ever driven other stuff? ive been at the helm of a camaro with a turbo 3.8 and took it up to 150mph on the freeway, and tried to get it to turn on twisty roads. my old sentra could handle more confidently.
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Old 02-12-2008, 07:02 PM   #37
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Re: Whats the point of Front Wheel drive?

Quote:
Originally Posted by KiwiBacon
If you're claiming that sway bars are a bad thing, then you'd have some serious arguments with anyone who designs or tunes suspension. The drive traction you are soo concerned about is only an issue in two situations. One is traffic light racing, the other is the 1/4 mile drags. In all forms of racing other than stupid straight lines it is not an issue.
A lot of people who think they are 'tuning' their suspension end up making things a lot worse. If you know how swaybars work you will know that what I said about them is true.

Drive traction is an issue any time you can spin the wheels. If you are a professional racer, or someone racing a higher end car, it matters a lot of the time. If you are someone racing a small, FWD economy car, or any car without much grunt, not so much.


Quote:
Originally Posted by KiwiBacon
You should have mentioned that earlier.
See the problem with your theory is that it hasn't been tested. The outlier at this stage is your lack of knowledge about the very vehicles you're discussing.
Hahaha, jesus, these are not my theories. Why don't you mosey on down to eng-tips and tell all the automotive engineers they haven't tested their theories enough. Then tell them you know this, because a mazda 3 can outbrake an RX-8 in the wet!

Quote:
Originally Posted by KiwiBacon
How about instead of throwing around numbers you picked out of thin air, actually delivering real numbers.
Like the stopping distance of a mazda 3 (fwd) vs an RX8 (rwd).

Oh look at that, the mazda 3 stops better in the wet.
http://www.rx8.co.nz/Reviews/pr_brake_2904.aspx

Take a look here and you'll see many fwd cars pulling up faster than the rx8 too.
http://www.movit.de/rahmen/stoptbl.htm
I have already explained this in my first two posts in my last reply to moppie. You should also read the exerpt from the book given up there.
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Old 02-12-2008, 07:07 PM   #38
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Re: Whats the point of Front Wheel drive?

This is now lapsing into little attcks against each other.

i'll put this simply:

if you can't put your point across without being whiny and bitchy, and can't accept each others' points of view, regardless of right/wrong i will close this thread.

this applies to everyone.
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Old 02-12-2008, 07:08 PM   #39
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Re: Whats the point of Front Wheel drive?

Quote:
Originally Posted by GreyGoose006
ding ding ding
we have a winner.

and guess what?
i actually really wanted one of those before i got my camaro
it was as simple as, i couldnt find one.

also, body build-quality is an issue too.
my camaro is rust free


whats funny is that from the right angles, they even look pretty similar
the daytona even has the "camaro" rear taillight triangles...
(if you havent noticed, when viewed from the side, the rear tailights form a triangle-esque shape
http://www.moparautos.com/images/84day2.jpg
Very good points. I've never understood why the rockers love to rust out on Daytonas and LeBarons. I guess I'll have to take a look when I cut my 1/4 panel off.
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Old 02-12-2008, 07:15 PM   #40
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Re: Whats the point of Front Wheel drive?

Quote:
Originally Posted by Nereth
A lot of people who think they are 'tuning' their suspension end up making things a lot worse. If you know how swaybars work you will know that what I said about them is true.
A swaybar can have a rate anywhere from imperceptible to stiffer than the chassis itself. To claim a sway bar "throws off bump handling" indicates a lack of understanding.

Again with reference to weight distribution. You need some data, not hand waving of what you think the weight distribution is.
It might help you understand why an audi A3 can stop harder than an RX8.

Quote:
Originally Posted by Nereth
Hahaha, jesus, these are not my theories. Why don't you mosey on down to eng-tips and tell all the automotive engineers they haven't tested their theories enough. Then tell them you know this, because a mazda 3 can outbrake an RX-8 in the wet!
I have read your excerpt and many others form Milliken. I conclude that you are attempting to apply them outside their intended context. In short I don't think Milliken would agree with how you are trying to use his words.

I am an engineer, I am familiar with eng-tips.com and I don't think the engineers there would agree with your blanket statements on the handling of vehicles you admit to not having driven.
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Old 02-12-2008, 07:51 PM   #41
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Re: Whats the point of Front Wheel drive?

Quote:
Originally Posted by KiwiBacon
A swaybar can have a rate anywhere from imperceptible to stiffer than the chassis itself. To claim a sway bar "throws off bump handling" indicates a lack of understanding.
If you have 60:40 weight distribution, and lets assume suspension design holds the tyres at opimum slip angle and camber for their load, and you have to use an roll axis that slopes upwards as it moves forwards (this is what most cars use I believe, apparently a comfort thing), and you are already quite possibly using softer springs on the rear (as the mass on the rear is less), then that leaves you with a car with more weight up the front, and more roll hardness up the front. To make up for that (in an attempt to get neutral handling), you need to add a lot of roll hardness at the rear, and the way to do that is a stupidly hard sway bar.

When one side of this sway bar hits a bump, the other wheel gets pulled up as well, decreasing traction even on the previously unaffected side. You are ruining part of the benefits you used to get from independent suspension. Yes if you had a soft sway bar this wouldn't be such a concern, but when you ask a swaybar to fix poor weight distribution and suspension geometry that isn't helping, you may not be able to make it soft.

Quote:
Originally Posted by KiwiBacon
Again with reference to weight distribution. You need some data, not hand waving of what you think the weight distribution is.
It might help you understand why an audi A3 can stop harder than an RX8.
What data do you want me to get exactly? Apparently the new A3 has a weight dsitribution of 58:42, and the RX8 has 50:50. Please do not keep making me reiterate that there is more to it than just being FWD, and just being front heavy. That's why I'm not giving examples. Are you sure tread compound, the ABS program, the weight of the vehicle, and all those other things aren't influencing the results?

Quote:
Originally Posted by KiwiBacon
I have read your excerpt and many others form Milliken. I conclude that you are attempting to apply them outside their intended context. In short I don't think Milliken would agree with how you are trying to use his words.
Well, one thing that I did fail to include in the quite was that he was talking about race vehicles, but as you probably know, I am also talking about race vehicles/high performance ones, because like I have said, problems start occuring when you start trying to put down a lot of power through the front wheels.

Anyway, I have quoted a large exerpt and I don't think it needs more context (it's certainly not worth typing out the pages either side of it). What you take from it is up to you, I have been pointing people to it because I don't think there is much else you can take from it.

Quote:
Originally Posted by KiwiBacon
I am an engineer, I am familiar with eng-tips.com and I don't think the engineers there would agree with your blanket statements on the handling of vehicles you admit to not having driven.
I have said twice explicitly that I'm not making blanket statements, and many other times implicitly. I know that there are FWD cars that can outhandle RWD cars. The point I am making, again, is that them being FWD is not helping. I think it is very rare when someone decides 'making this car FWD will help lap times'. The only time I can see that happening is low friction surfaces where load transfer doesn't have much chance to take effect, so you can end up with more load over the drive wheels.

For the record, I have driven my fair share of FWD cars, but not in a performance situation. Even if I had, I can hardly trust the seat-of-the-pants measurements I would have come up with.
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Old 02-12-2008, 08:39 PM   #42
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Re: Whats the point of Front Wheel drive?

Quote:
Originally Posted by Nereth
A lot of people who think they are 'tuning' their suspension end up making things a lot worse. If you know how swaybars work you will know that what I said about them is true.

Drive traction is an issue any time you can spin the wheels. If you are a professional racer, or someone racing a higher end car, it matters a lot of the time. If you are someone racing a small, FWD economy car, or any car without much grunt, not so much.
A lot of people think that lowering the car as far as possible will make it handle better but they end up going below the roll center and screwing up their camber and throwing the suspension geometry all off. Then they just add thick sway bars front and back with subframe connectors and strut tower bars not taking in to how the car handles at the limit. They also tend to buy dampers that aren't dampened properly for the springs and don't even pay attention to spring rates. Some people just heat their stock springs or cut progressive springs. Truth be told, most people should even try modding anything on their cars. SCC has a few good articles explaining how to do your suspension right. I thought they were very good.

Also, I do agree with you about limits to FWD. You really don't want to go much past 350 hp or you're asking for potentially asking for traction issues, shearing axles, and blowing up CV joints.
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Old 02-12-2008, 08:54 PM   #43
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Re: Whats the point of Front Wheel drive?

Quote:
Originally Posted by Nereth
If you have 60:40 weight distribution, and lets assume suspension design holds the tyres at opimum slip angle and camber for their load, and you have to use an roll axis that slopes upwards as it moves forwards (this is what most cars use I believe, apparently a comfort thing), and you are already quite possibly using softer springs on the rear (as the mass on the rear is less), then that leaves you with a car with more weight up the front, and more roll hardness up the front. To make up for that (in an attempt to get neutral handling), you need to add a lot of roll hardness at the rear, and the way to do that is a stupidly hard sway bar.
see, your problem is moderation.
lets say we take your example of a fwd car with a 60:40 f:r weight distribution.
now, lets say that instead of using spring rates as a comparison, we use spring frequency, or hertz. wheel hertz more specifically.
now.

your typical 4dr import sedan has spring frequencies in the 1.3-1.7 hz range.
typically, 1 hz is known as the "brown frequency" and makes people get sick, so it is avoided.

anyway, lets say that for fun, this car has a front spring frequency of 1.5 hz and a rear frequency of 1.6 hz.

this also makes sense as the normal practice for suspension tuning is to make the rear frequency slightly higher than the front frequency so that the cars oscilation front to back will not be un-checked.
if they were both 1.5 hz, the car would tend to rock front to back endlessly. the back is made higher than the front because it helps the rear end "catch up" to the front end after hitting a bump.

now lets assume that since the rear has a higher frequency, it must have a slightly higher roll stiffness.
knowing that understeer is considered safe, an anti-roll bar is fitted to the front of the cars suspension.
lets say for arguments sake that the arb contributes 75% of the roll stiffness of the springs.

this means that if the springs contribute 100 lbft of roll stiffness, the front arb contributes 75 lbft.
i dont know if this is exact, but following your gross estimations, i would not think that this is too far off.

this means that the front now has a much higher roll stiffness than the rear of the car and the car has a natural understeering tendancy built in.

if a rear anti roll bar is desired to add a bit of "sport" to the feel of the car, one may be added.
lets say that the bar on the rear also has a rate equal to 75% of the roll stiffness of the springs.

this means that the roll stiffness of the front is still higher than that of the rear, but the rear is higher, as a percent, with respect to weight.



Quote:
When one side of this sway bar hits a bump, the other wheel gets pulled up as well, decreasing traction even on the previously unaffected side. You are ruining part of the benefits you used to get from independent suspension. Yes if you had a soft sway bar this wouldn't be such a concern, but when you ask a swaybar to fix poor weight distribution and suspension geometry that isn't helping, you may not be able to make it soft.
again, yes, but you are taking it to the extreme.

http://www.sfxperformance.com/parts/HOT804121.htm

this is a link to a sway bar kit for a toyota scion xb.
it is a relatively well mannered car.

notice that the front sway bar is 1.125" and the rear bar is .5"
i am willing to bet that you could twist that rear bar with your bare hands.
(well not necessarily you, but i surely could.)
if you go and look at kits for other popular import cars, you will see a similar trend.

in the case of the xb, i am willing to bet that the rear bar is nowhere near 75% of the roll stiffness of the springs. it is most likely nearer to 20%



another thing you are overlooking, especially in the case of a fwd vehicle, is the differential.
the differential, in my opinion, is responsible for more of the way a fwd car handles than the suspension its self.
a lsd with the right tuning (high torque under power, low torque under coast) can give the car LOTS of lift off oversteer.
if a car is understeering, all the driver has to do is give it a shot of gas and lift off while increasing the steering angle and voila, oversteer out whe wazoo.

on the contrary, a rwd car that has lots of power but is being set up "safely" for understeer, will have a low locking torque under power. this will let the driver have fun getting the rear end out.
the coast torque is set much higher though, so that when the driver lets off the gas in the middle of a tail-out turn, the rear will gain traction and come back into the correct line.



i recommend this program to you
http://www.vehicle-analyser.com/

go ahead and download the lfs version because it includes more car types.

play around with it and you will begin to understand what i, and others here are saying.
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Old 02-12-2008, 08:58 PM   #44
KiwiBacon
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Re: Whats the point of Front Wheel drive?

Quote:
Originally Posted by Nereth
If you have 60:40 weight distribution, and lets assume suspension design holds the tyres at opimum slip angle and camber for their load, and you have to use an roll axis that slopes upwards as it moves forwards (this is what most cars use I believe, apparently a comfort thing), and you are already quite possibly using softer springs on the rear (as the mass on the rear is less), then that leaves you with a car with more weight up the front, and more roll hardness up the front. To make up for that (in an attempt to get neutral handling), you need to add a lot of roll hardness at the rear, and the way to do that is a stupidly hard sway bar.
Lets start with the errors in this paragraph.

Firstly, the roll axis slopes up towards the rear on every vehicle I've looked at. That is, the rear suspension roll centre is higher than the front.
The roll axis is the result of the roll centre, not the other way around.
This is another reason why many production vehicles have sway bars fitted to the front and not the rear.

Secondly, talking spring rates doesn't mean much without including the sprung weight at that end. You probably don't realise but the natural frequency of the suspension matters most and rear suspension is often tuned to have a higher frequency than the front. One of the goals is to prevent see-saw pitching.

You do not need a "stupidly hard bar" in the rear, I have no idea where you got this idea from, but it possibly stems from you getting the roll axis wrong above.
As I've said, normally you need no sway bar in the rear, if you do need to add one to tip the balance, it's rate does not need to be high at all. One of the purposes of a sway bar is to cause faster load transfer to the outside wheels.
The higher roll centre of the rear wheel already causes faster load transfer without needing additional roll-stiffness to acheive that.


There's a catch with applying theories, the catch is you need to understand them well enough to apply them correctly. I'm convinced that on this subject you don't.
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Old 02-12-2008, 09:25 PM   #45
Nereth
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Re: Whats the point of Front Wheel drive?

I'm going to ahve tos plit my replies to you guys up into parts - there is a lot to say.

Quote:
Originally Posted by Polygon
A lot of people think that lowering the car as far as possible will make it handle better but they end up going below the roll center and screwing up their camber and throwing the suspension geometry all off. Then they just add thick sway bars front and back with subframe connectors and strut tower bars not taking in to how the car handles at the limit. They also tend to buy dampers that aren't dampened properly for the springs and don't even pay attention to spring rates. Some people just heat their stock springs or cut progressive springs. Truth be told, most people should even try modding anything on their cars. SCC has a few good articles explaining how to do your suspension right. I thought they were very good.

Also, I do agree with you about limits to FWD. You really don't want to go much past 350 hp or you're asking for potentially asking for traction issues, shearing axles, and blowing up CV joints.
I agree with basically everything you say. People think that hardening suspension endlessly makes the car handle. It's why a lot of people worship the swaybar and think thicker is better no matter what.
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