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By design all domestic cars under-steer!


Tony
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Refer to my post above. rolleyes_anim.gif

 

I believe it is because the average car driver suffers from extreme numptiness! From a legal perspective an understeering car is easier to control for these numpties. If a car gained a reputation for being difficult to control and more accidents followed, this could be very damaging and possibly expensive.

 

I understand that final development will still be achived by a bloke driving it with adjustments to produce the desired understeer tendancy.

 

With regard to the legal perspective, this still bothers me slightly. recently had a 944 turbo back in, a regular customer, whos setup i thought was very good, with progresive controllable oversteer. During my inital setup, i had run the rear antiroll bar at its stiffest setting, but found that it was quite twitchy, very difficult to catch the rear when it did break away. So i put it back to its mid setting.

 

On his most recent visit he wanted it set to the stiff postion to take advantage of the better level of grip this offers. I discussed the downsides of this but did it for him nonetheless. He is a competent driver, with considerable track experience so i went with it.

 

The same car in the hands of someone less capable (ie numpty) however, is likely to end up in a hedge!

 

I think we are actually faced with the same choice as the manufactureres, but on an individual vehicle basis. To date, i don't think anyone has ever considered pursuing the individual who has setup a car following an accident, but i do think it will happen one day.Imagine getting it wrong on a mass produced basis. Understeer = minimum risk.

 

I think that all makes sense, even if i did ramble a bit.

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Roger.... You did just fine rolleyes_anim.gif

We need to concentrate on the manufactured Domestic car though rather than the sort of evolution we develop for our modified market (chassis calibration)

 

For the Domestic market as you say the cars ultimate goal is to save the driver however "numpty" This is achieved by the Yaw demand? a definitive expression that encompasses all cars.

Transient yaw that amplifies mechanical departure or pneumatic departure expectations by design.. Meaning that (domestically) if the steering yaw exceeds the chassis design characteristics then the car is expected to crash!.... The under-steer desires this non-recoverable transient as head on, allowing the most protection for the driver... Crumple progression and air bags galore..

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Don't forget cars loads too.

 

A car that understeers a tiny bit / is neutral with just the driver in could quite easily oversteer into a hedge with a full boot, tank of fuel and 2 people in the back. The chassis has to handle predictably in ALL load conditions hence building in quite a margin.

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Don't forget cars loads too.

 

A car that understeers a tiny bit / is neutral with just the driver in could quite easily oversteer into a hedge with a full boot, tank of fuel and 2 people in the back. The chassis has to handle predictably in ALL load conditions hence building in quite a margin.

 

 

Beautifully summed up by Sam@tdi

Quote:-

Regarding family cars, most tend to be a little higher than 1.00 and tend to get a lot more so as they are loaded with passengers or luggage. You would be amazed how massively far out some cars are. For instance the classic VW beetle which believe it are not has a weight distribution not too far away from 50/50 actually has a DI of 0.48 and I think it's a well know fact that an un-modified one is just straight up dangerous when approaching the grip limit laugh.gif This is usually as a result of a project going to the design house before it goes to the dynamics engineers.

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I think the key fact, whatever we might call it the, result, is to reduce the risk of comeback to the manufacturer to the minimum. Im sure occasionally they still get it slighlty wrong, but doubt there are and "classic VW" type handling issues out there any more.

 

Just look at the ford explorer? tyre problem to see how getting it just slightly wrong can cost big! Different issue i know, but it is ultimately about risk reduction (to the manufacturer).

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I think the key fact, whatever we might call it the, result, is to reduce the risk of comeback to the manufacturer to the minimum. Im sure occasionally they still get it slighlty wrong, but doubt there are and "classic VW" type handling issues out there any more.

 

Just look at the ford explorer? tyre problem to see how getting it just slightly wrong can cost big! Different issue i know, but it is ultimately about risk reduction (to the manufacturer).

Since this topic is a debate. How should we analyze the customers comments that the car "over-steers".

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I think the key fact, whatever we might call it the, result, is to reduce the risk of comeback to the manufacturer to the minimum. Im sure occasionally they still get it slighlty wrong, but doubt there are and "classic VW" type handling issues out there any more.

 

Just look at the ford explorer? tyre problem to see how getting it just slightly wrong can cost big! Different issue i know, but it is ultimately about risk reduction (to the manufacturer).

 

Seriously you would be amazed, the Rover groups MGF was a DI tragedy and they had plans in the pipeline to replace it with something way worse before they went belly up, simply because it looked good :guitar:

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I think the key fact, whatever we might call it the, result, is to reduce the risk of comeback to the manufacturer to the minimum. Im sure occasionally they still get it slighlty wrong, but doubt there are and "classic VW" type handling issues out there any more.

 

Just look at the ford explorer? tyre problem to see how getting it just slightly wrong can cost big! Different issue i know, but it is ultimately about risk reduction (to the manufacturer).

 

Seriously you would be amazed, the Rover groups MGF was a DI tragedy and they had plans in the pipeline to replace it with something way worse before they went belly up, simply because it looked good :)

I confess i don't see many MGF's but those i do are dire in the chassis department.... Great shame really because i actually like the look of the car?

 

Note to all: Please don't hit the face :)

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The reasoning is correct IMHO, who as a "responsible" manufacturer would want to be seen as producing fast turn in cars.

Not going to happen in this compensation culture society we live in.

 

Thankfully we're still a fair way behind the states with regards to litigation and lawsuits.

 

In my opinion we should just take the warning labels off everything and let natural selection take it's cause.

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The reasoning is correct IMHO, who as a "responsible" manufacturer would want to be seen as producing fast turn in cars.

Not going to happen in this compensation culture society we live in.

 

Thankfully we're still a fair way behind the states with regards to litigation and lawsuits.

 

In my opinion we should just take the warning labels off everything and let natural selection take it's cause.

 

Yep

but we are quite often talking about cars specifically designed for the US market and we seem to follow their geo settings.

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  • 2 weeks later...
The reasoning is correct IMHO, who as a "responsible" manufacturer would want to be seen as producing fast turn in cars.

Not going to happen in this compensation culture society we live in.

 

Thankfully we're still a fair way behind the states with regards to litigation and lawsuits.

 

In my opinion we should just take the warning labels off everything and let natural selection take it's cause.

 

Yep

but we are quite often talking about cars specifically designed for the US market and we seem to follow their geo settings.

Why! The UK requires specific chassis dynamics, where is the development system failing? Do you follow the US settings.... cos i can "cat kicking assure you" i don't.

 

post-2-1171576733_thumb.jpg

 

One i launched yesterday :lol:

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