ozzy

Where's Mycroft when you need him to explain it all

I think SDB would be more educated to tell us the pro's and con's in the cornering debate.

Certainly what I've noticed with the Scoob is if you think you've misjudged a bend, most of the time it's best just to hang on or even push on as the car will generally start giving you more grip.

If you panic, lift off or keep braking it'll get really upset and start sliding around.

Of course if it's even slightly wet and you're running Toyo's then start praying

Stefan

LG John

Ozzy, I find with a scooby that when you think you've misjudged a corner you usually have and you left in the lap of the gods! A certain other car I owned used to seem to pull you out the **** from nowhere. In fairness though I usually find that I'm chucking the scooby into a corner 10mph faster than I would that other car which probably doesn't help

john banks

What does the outside front wheel contribute then?

Perhaps the Carrera 4 is not a handful in the wet because of its big tyres because it is not a Carrera 2?

Cosworth427

================================================== ================

"What does the outside front wheel contribute then?"

================================================== ================

Not much, especially when the car will transfer weight rear wards when you apply throttle, which then unloads the two front wheels further. Upon exit of a corner with throttle, you'll have a diagonal transfer of weight (weight to outside wheels during cornering, and then weight to the rear outside wheel after throttle is applied.)

It is the inside rear wheel that will provide effective extra traction, not the outside front. Again, shocks, strut braces, bars and springs are tuned to load that wheel up.


================================================== ================

"Perhaps the Carrera 4 is not a handful in the wet because of its big tyres because it is not a Carrera 2?"

================================================== ================

???? Your logic says that wide tyres (255-265) is a peice of **** when it comes to wet weather driving, and I provided you with cars that have wider tyres and they manage fine. Compounds and tread design make more of an effect on wet road grip than a couple of extra cm of width of rubber.

akshay67

That's 2 of us then...who willing to donate a CL55 AMG?

The weather will donate the rain.

Wales will donate the twisties.

Bring it on!!

LG John

Tyre width to weight ratio has to play a pretty important role surely? The VTS has 195/45 tyres (i think) and 960kg but the scooby has slightly wider tyres but a more flexible sidewall (205/50 (i think)) and a lot more weight. My old mans 330d used to hold on pretty well and it had fairly fat rear wheels.

LG John

Wales, pah...Scotland would be better and it will likely donate the rain no problem

Cosworth427

================================================== =================

"Tyre width to weight ratio has to play a pretty important role surely? The VTS has 195/45 tyres (i think) and 960kg but the scooby has slightly wider tyres but a more flexible sidewall (205/50 (i think)) and a lot more weight. My old mans 330d used to hold on pretty well and it had fairly fat rear wheels."

================================================== =================

Changing the tyre width is more to do with changing the spread of the contact patch rather than this so-called weight to width ratio.

Applying wider tyres at the rear is a way to tune power oversteer, because of the slip angle difference between the rears and fronts. More slip angle at the rear wheels means more oversteer upon thottle in a RWD car. Wider tyres keeps that slip angle minimised to control that oversteer. Of course, shocks, springs are tuned to control that too.

john banks

Manage fine is all relative. Manage fine is different to exquisite traction out of a wet corner without drama. Are you telling me that a C4 and a C2 if they had the same tyres would be equally competent in the wet? Why do AWD versions of the same/similar car lap quicker?

I am still getting SOME traction through my front outside wheel pulling out of bends am I not? (And I still getting some through the inside wheels too?)

Should we just throw away AWD then if it is no improvement in traction out of corners in the wet and have RWD and wide tyres?

SiPie

Wales is fine by me..... the rain will just follow me anyway

Is there an AMG forum or similar where someone with enough silly money will actually take up the challenge if we advertise the fact..that we are insane enough to take them on

Timed A to B runs over a nice VERY TWISTY SECTION of Wales' finest black stuff

John

Keep the AWD

[Edited by SiPie - 8/14/2003 5:06:14 PM]

Dracoro

What %age of the time are people actually pulling out of a corner going full pelt that traction will come into the equation?

Yeah when it is slippery, losing traction the 4WD is useful but most the time traction isn't lost on a car like a CL55 and it can use all it's many horses to the full and outrun cars like scoobs etc.

On a really tight twisty rough surfaced bit of road 4wd wins but in the vast majority of road and track conditions the number of wheels driven is not really an issue.

john banks

With 200 BHP in the dry then two wheel drive on smooth tarmac is probably an advantage. When it tips it down like it often does here you end up slithering around all over the place, whereas a standard Impreza with 215 BHP is really quite easy to handle even when it is tipping it down.

Tune the motor to decent levels of torque especially if it is turbocharged and AWD struggles down bumpy roads in the dry. It can be fun keeping the car pointing in a straight line in 2nd and 3rd gear. I would not bin the AWD for anything.

A 700+ BHP Supra is hilarious to watch doing a straight line sprint at Knockhill - it is all over the place all the way to the finish line in the dry. A 320 BHP Sunny whips its *** but is less entertaining to watch and I am sure to drive

mattstant

.

What the ***** wrong with Toyo's they are superb in the wet and a very good all round tyre

LG John

Clearly you've not been in the car with Simon. Its easier to measure the percentage of time that all four wheels have clean contact with the road and its usually about 10%

Cosworth427

================================================== =================

"Manage fine is all relative. Manage fine is different to exquisite traction out of a wet corner without drama. Are you telling me that a C4 and a C2 if they had the same tyres would be equally competent in the wet? Why do AWD versions of the same/similar car lap quicker?

I am still getting SOME traction through my front outside wheel pulling out of bends am I not? (And I still getting some through the inside wheels too?)

Should we just throw away AWD then if it is no improvement in traction out of corners in the wet and have RWD and wide tyres?"

================================================== =================


Again, you and a few others here are making the assumption that just because it is AWD, that makes the car quicker in a corner, and I'M TELLING YOU(s) AGAIN that it is more to do with the suspension geometry, tyres and weight distribution.

The 996 Carrera and the Carrera 4 are not similar cars, especially the difference in spring rates and shock rates. (C4 is stiffer set). That difference will more likely affect how well and how fast those cars will perform.

You cannot sum up some ignorant conclusion based on a few magazine tests, when you haven't even considered the set up of the cars that were tested, let alone UNDERSTAND the set up of the car.


"I am still getting SOME traction through my front outside wheel pulling out of bends am I not? (And I still getting some through the inside wheels too?)"


ONCE again, that "some" traction is only a very small margin, and that traction is decreasing upon unavoidable weight transfer to the rear. Loading the inside rear wheel will provide far more traction and will not diminish as you apply more thottle, since the rearward weight transfer is loading those rear wheels.

Cosworth427

================================================== =================

"With 200 BHP in the dry then two wheel drive on smooth tarmac is probably an advantage. When it tips it down like it often does here you end up slithering around all over the place, whereas a standard Impreza with 215 BHP is really quite easy to handle even when it is tipping it down.

Tune the motor to decent levels of torque especially if it is turbocharged and AWD struggles down bumpy roads in the dry. It can be fun keeping the car pointing in a straight line in 2nd and 3rd gear. I would not bin the AWD for anything."
================================================== =================


Read my last post and STFU.

Dracoro

Saxo Boy - Sounds like an interesting ride, give me his number! sounds like fun

ozzy

I hope they are for you. Personally, I hate the ******* and will never go back to them unless I can try them out first. Car handles like a shopping trolley in the slightest bit of rain. 40mph and it's sliding around roundabouts and mine aquaplanes (spelling?) like a set of slicks.

All IMHO of course.

What PSI you running on them. That's my last hope for them.

Stefan

john banks

Can you spell out STFU for me please?

Are you telling me that all other things being equal that the AWD car will not have superior traction coming out of the corner?

Why don't Porsche just sort their spring and shock rates then and not bother at all with the hassle of making the C4?

Why is it that when you adjust the centre diff away from the rear in the wet that a Type R gets out of corners better under power?

Are you suggesting we bin AWD to make competent wet weather cars?

How does a FWD car get out of a wet corner if there is hardly any traction available to the front wheels?

john banks

http://www.scoobynet.co.uk/bbs/threa...ThreadID=13037

Has Simon summed up some of what you are saying here?

Can I be clear I am mainly asking questions here because I am happy to learn. I am not saying AWD is better in "The Twisties" (TM) than RWD, I am wondering if it has superior traction pulling out of a wet corner because everything I have experienced suggests it does. However, I could be ignoring confounding variables in assuming this and am willing to be convinced otherwise.

If AWD does not have superior traction out of wet corners then all it is actually useful for is straight line traction? But this just does not ring true with what I experience when I drive - unless I have not driven the right RWD cars to experience serious wet weather pull out of bends. This is about the Scoob's only ace card are you saying it is actually pointless and they may as well just have done RWD and done it properly?

Why are AWD cars universally acclaimed to be wet road kings? Is it because they don't bin you into a hedge, or is it as I think it is that in the hands of drivers of equal abilities they cover ground quicker?

I am not saying that the Scooby is better than a CL55 AMG LOL. Far from it!

What are your biases Cos247? Do you dislike AWD and feel it has no value whatsoever? Are you merely trying to dispell myths such as the common one that steady state cornering is better with AWD? There are a lot more people that believe that AWD provides superior traction out of wet corners who would consider themselves informed? Are we all wrong or is it just me?

What would be your ideal bumpy road wet weather car? What is the fastest real world production A-B car on the planet in soaking wet conditions?

Mine would be an Evo or a Scoob, and I presume a 911 Turbo (not driven). All happen to have AWD.

Any reason I should take an M3 or an Elise down that wet road?

Now I know you don't like motoring journalists, but in the real world a lot of us can't get access to the supercars so they are well read and appreciated... why do they all complain about lairy RWD cars in the wet or very active traction control systems on the recent powerful Mercs? Are they just crap drivers who should confidently be dicing with oversteer in really wet conditions?

Can you do better? If so you are far braver than me in the wet, 100 BHP to each wheel in the wet in anything I have driven can be very snappy indeed. That oversteer can very quickly turn into a spin.

Have I missed your point?

[Edited by john banks - 8/14/2003 8:12:21 PM]

TonyBurns

iTrader: (3)

SB,
I had a play with an SL55 AMG last week, these are a little more expensive than the CL (5k more?) but he was playing with me (definately )
Beautiful cars, definately more powerful than my scoob and would leave me for dead.

Tony

LG John

ROTFLMAO I think John just asked the most amount of questions in a single post ever

SiPie

Mattstant

This is where I am for once perfectly placed to comment and totally disagree

Just went from so2'S, to Yokohamas, to SO3'S to Proxes, to Goodyear F1'S, then back to Proxes (all on 16's)

The return to Proxes was forced as I bought a set of wheels and they were shod with very good Toyo rubber so thought it rude not to use it.

The tread on the Goodyears (exluding outside edge ) was a dead match with the Proxes at 7mm.

Took the car out the last 3 nights (night 1 on F1'S, then last 2 on Proxes) and even in the dry the Proxes loose all out grip at a point around 20% sooner than the Goodyears. Fact.

Now admittedly they are more progressive than the F1's but you are more often sliding on the Proxes where the F1's wouldn't even of given a squeek.

I went through my favourite set of twisties in identical conditions (probably identical temperature) time after time to re-accquaint myself with the old sliders and to get through them at exactly the same pace on the Proxes I had broken traction almost 100% of the time to maintain the same speed. Was alot more hard work. More fun but not as safe

I am not looking forward to the first bit of wet weather where I agree with Ozzy 100% and remember the Proxes being great at shifting large amounts of standing water, hence few aquaplaning moments but they do not deal well with normal wet or especially damp conditions

If you think they Proxes are a good tyre then treat to yourself to some (admittedly quick wearing ) Goodyear Eagle F1 GSD3's

Cheers

Tyre rant over

PS Who has this Merc then

Cosworth427

================================================== ================
"Are you telling me that all other things being equal that the AWD car will not have superior traction coming out of the corner?

Why don't Porsche just sort their spring and shock rates then and not bother at all with the hassle of making the C4?"

================================================== =================


I'm going to say this once *again*, it all falls down to suspension, tyres and weight distribution. A FWD, AWD or RWD will only handle well and have enough traction as far as the suspension and tyres allows them to have. The suspension settings between a C2 and C4 is a matter down to Porsche's own judgement & criteria, and not mine or yours or anyone elses. The 996 Carerra is the most road friendly 911 ever, using actual race or near race level set up on its shocks and springs isn't going to be much fun when the majority of 911 drivers will be using them on the road. You ask why doesn't the 911 use stiffer springs. The same question could be asked to *any* car manufacturer with the performance models they have for the road. It is about compromise.

Alot of members here have this belief that RWD in essense bad for all-weather driving and will always be slower in corners, while that AWD rule simply because it has more driven wheels. This belief COMPLETELY disregards the real main factors; suspension, tyres, weight distribution. In motorsport, careful managment of these factors makes the great handling AWDs handle. It makes the great handling RWD cars handle, it makes the great handling FWD cars handle.

If I were to configure my car for better handling and improved on throttle grip in corners, I'm not going to say...

"Right, let's buy a sophisticated 4WD splitter, extra prop shafts, so we can add weight, complexity and lose even more power at the wheels just so we can get that little *extra* traction from the front wheels, when I could just get the right shocks, springs and bars to help load the inside wheels better so I can get back the lost power out of a corner."

But then again, I could set my AWD, FWD or RWD car up that will grip like hell on a track but totally shake my teeth off when I drive home. Again, it's all about compromise. But the point STILL is that RWD, FWD handles WELL because of the setup, not simply because of where or how many of the wheels are driven!


================================================== ===============
"Any reason I should take an M3 or an Elise down that wet road?"
================================================== ===============

Accidents or losing complete traction is a cause by human error and/or lack of driver skill. I don't see F1 drivers refuse to drive in the wet just because they have 800 HP RWD cars. And those F1 cars can still corner at higher speeds than any Impreza or EVO on wet roads. I guess it must be some emergency AWD module hidden in those F1 cars that did it huh?

I'll go back to my point again just to remind everyone. A powerful CL55 will handle and have grip unless AMG/Mercedes deliberately de-tuned it so it won't. But I doubt that, as it would waste the need for fully independent multi-link style suspension and wide tyres. It (like every road car on the planet) doesn't use it's maximum power in a tight corner. (Which is why a 290 hp NSX TYPE-R will be just as fast as an AWD 550+HP Murcielago in a bend.) A CL55 will stay in a corner as much as the tyre and suspension can do its work. Much like an AWD Impreza's suspension and tyres would!

john banks

Thankyou. Please don't get impatient with me the number of times you feel you have to explain it. If I don't get it then I assume I am not the only one.

So is there any point in having AWD except for straight line traction? I think you are saying no?

Are you saying there is some extra traction out of corners with AWD but not enough to justify it given the weight/losses/complexity? Or are you saying ther is NO extra traction out of corners with AWD?

[Edited by john banks - 8/15/2003 3:33:19 PM]

Cosworth427

================================================== ================
"So is there any point in having AWD except for straight line traction? I think you are saying no?

Are you saying there is some extra traction out of corners with AWD but not enough to justify it given the weight/losses/complexity? Or are you saying ther is NO extra traction out of corners with AWD?"
================================================== ================

I think you've forgotten why Subaru and Mitsubishi use AWD.

...Rallying.

Much like Audi did with their Quattro system. The use of AWD is clear when the variable surfaces rally cars have to ride on make the theories of inner wheel loading almost inapplicable ( althought it can still help on drier harder surfaces) Having one front wheel driving while the other 3 are in mid air is better than having no front wheel drving at all (RWD cars). Having both rear wheels in 3 inches of mud in a RWD car will get you no where fast, but with AWD you atleast have one of the front wheels to get you out of trouble. (Ask Land Rover about that).



[Edited by Cosworth427 - 8/15/2003 3:44:41 PM]

john banks

So on wet smoothish tarmac you may as well have RWD or a Skyline type or Subaru Type R system? By moving the centre diff from rear bias on a Type R in the wet we are not making it quicker just making it less likely to bin it into roadside furniture because of amateur drivers?

Cosworth427

================================================== ================
"So on wet smoothish tarmac you may as well have RWD or a Skyline type or Subaru Type R system? By moving the centre diff from rear bias on a Type R in the wet we are not making it quicker just making it less likely to bin it into roadside furniture because of amateur drivers?"
================================================== =================

As far as the R33 is concerned, it is essentially RWD until oversteer has been detected, so torque gets transmitted to the front to *tighten* the car, safety rather than all out better lap times.

john banks

Thanks.

Are you an automotive engineer?

LG John

You need to try out some of the broken, patchy, mud spilt scottish twisties mate I agree with you that on most a and b roads AWD isn't much of an advantage but I'm talking about the sort of c class roads that I seek out for fun and which are in abundance up here - this is where AWD comes into its own and in the hands of simon cannot be caught by a 2wd car