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Insight6

join:2012-08-25

V8 high performance: 4matic v RWD

Now I'm old. In my prime I did some very low level amateur road racing. One thing for sure whatever my skill level is now its way below one was in the good old days.

I'm lusting at buying a new Mercedes E or S class, AMG or standard.

I'm wondering what specifically in clear practical terms are the handling difference of a 4matic v RWD on a winding road when pushing any of these cars.

Now I can't find any real understandable practical information on this. When I've found some comparisons the information conveyed is ambiguous.

My year round environment is mild. No snow or ice. So how do the comparable 4matic compare to the RWD equivalent?

In my prime when pushing the car I preferred a neutral setup or a bit of oversteer. I definitely didn't care for any understeer.

Now for production passenger cars, even high performance one like above with RWD or 4matic there based upon what I heard a bit of understeer.

Question: Say you have a choice between the exact same car in either 4matic or RWD. What precisely are the differences in the road handling of the car on a quick winding road in good condition and fair climate?


CylonRed
Premium,MVM
join:2000-07-06
Bloom County

1 edit
Just about all performance cars are geared toward understeer - it is a bit safer than oversteer. In general - 4 wheel drive will get you better handling. Where did you find the information about either ambiguous? I have found that car magazines generally are not all that ambiguous.

To really know the differences - you personally would need to drive them. What is a horrible amount of understeer for you might be ok for someone else and vice versa.

Article on the web from March of this year on the 4matic:
»www.autoguide.com/manufacturer/m···888.html
--
Brian

"It drops into your stomach like a Abrams's tank.... driven by Rosanne Barr..." A. Bourdain


I AM
Premium
join:2010-04-11
Ephrata, PA
kudos:4
reply to Insight6
Now, I haven't really raced cars or anything so take my opinions as you may. There's a reason why most true sport cars out there are RWD. If I lived where there was no snow all my cars would be RWD, I do and my car is still a MR. I drive a little roadster that's rwd and it far more funt o drive than any FWD car I've owned.


Insight6

join:2012-08-25

1 edit
reply to CylonRed
said by CylonRed:

To really know the differences - you personally would need to drive them. What is a horrible amount of understeer for you might be ok for someone else and vice versa.

Article on the web from March of this year on the 4matic:
»www.autoguide.com/manufacturer/m···888.html

Thanks for the post and the linked article. But it is too is ambiguous in the context of my OP, that perhaps you didn't catch the guest of my post. If that is so it is because I was too long winded and not specifically clear. Sorry about that.

So here is the OP trimmed down and tuned up or tweaked with some new language.

said by Insight6:

I'm wondering what specifically in clear practical terms are the handling difference of a 4matic v RWD on a winding road when pushing any of these cars to go very fast .

Question: Say you have a choice between the exact same car in either 4matic or RWD. What precisely are the differences in the road handling of the car [AWD v RWD] that you are driving fast on a quick winding road in good condition and fair climate?

Simply FYI, no one that drives fast or wants to try and drive fast likes understeer. High performance, (high skid pad ratings) high powered production sedans designed to drive fast only have a slight bit of understeer.

I wouldn't even try to drive a FWD car fast except in a straight line.

(To put the linked article in perspective notice all of the pictures showing the car in snow! The article is directly and also by inference addressing the handling of the AWD in slippery conditions. )

I'm talking only about driving fast on a winding road that is in good shape. You know where you turn off the traction control--which only gets in the way for high speed twisting road handling.


CylonRed
Premium,MVM
join:2000-07-06
Bloom County
I guess I don't know what you mean by ambiguous then - as I read that in the original post but in scanning the article - I did not find it that ambiguous.

No one likes understeer but you will need to tune that out on a production car as it is safer to have understeer (in general).

FWD can be fun at tracks like Mid-Ohio - my Civic HB was a blast - turn one at 70 mph...

It really IS going to boil down to you driving both versions. over\understeer is going to be rather subjective from driver to driver.

In general - a limited slip diff or 4 wheel drive will be best for performance driving. Understeer will need to be removed after purchase via setup. In my case - my 330i needs to have a square wheel setup at a minimum to reduce understeer.

The main thing to think of - 4 wheel drive is going make the car heavier and will change the driving characteristics (at least it can).
--
Brian

"It drops into your stomach like a Abrams's tank.... driven by Rosanne Barr..." A. Bourdain


Insight6

join:2012-08-25

1 edit
said by CylonRed:

In general - a limited slip diff or 4 wheel drive will be best for performance driving.

The main thing to think of - 4 wheel drive is going make the car heavier and will change the driving characteristics (at least it can).

Good post but we are still not on the same page.

First off, I'm sure you meant all wheel drive when you said 4 wheel drive but I just wanted to point it out so we are thinking about the same thing.

I'll put it to you this way. Say I have two V8 high performance and high quality vehicles. One has all wheel drive and the other has RWD. They are otherwise identical. We electronically tune the horsepower of the vehicles to compensate for the extra weight of the 4matic drive.

We take the cars to the Nurburgring track and run a lap as hard as we can with a professional driver. The weather and track are ideal conditions with a perfect track. I know which car will be faster. What are the handling differences between the two cars?

Kearnstd
Space Elf
Premium
join:2002-01-22
Mullica Hill, NJ
kudos:1
reply to Insight6
In theory the AWD should always be ahead in handling and when you get a bit of rain the AWD will continue to grip. Pretty much why everybody offers AWD now, Though only Subaru and Audi have it factory standard across the entire model line.
--
[65 Arcanist]Filan(High Elf) Zone: Broadband Reports


mob
On the next level..
Premium
join:2000-10-07
Reviews:
·SureWest Internet
reply to Insight6
said by Insight6:

We take the cars to the Nurburgring track and run a lap has hard as we can with a professional driver. The weather and track are ideal conditions with a perfect track. I know which car will be faster. What are the handling differences between the two cars?

The heavier car will scrape more often, bottom out more often, bumpsteer will be a bigger problem, etc. The heavier car may need different tires and springs to cope with the added weight.

Some speed shops will take a client Lamborghini with AWD and convert it over to RWD only....just putting that out there.
--
Ich habe kein Mitleid - Me
You're a daisy if you do. - Doc Holliday
And as always, have nice day.


Cho Baka
Premium,MVM
join:2000-11-23
there
kudos:2
Reviews:
·TekSavvy DSL

1 recommendation

reply to Insight6
said by Insight6:

We electronically tune the horsepower of the vehicles to compensate for the extra weight of the 4matic drive.

LOL at the marketing BS.
--
The talented hawk speaks French.


Insight6

join:2012-08-25
said by Cho Baka:

said by Insight6:

We electronically tune the horsepower of the vehicles to compensate for the extra weight of the 4matic drive.

LOL at the marketing BS.

Marketing BS? What I mention is done all the time for testing purposes in modern high tech high performance autos. It's not a marketing issue or venue. Usually the electronic adjustment or tuning is to increase the output. So in our hypothetical the most likely scenario is to increase the HP in the 4matic to offset the increase in weight of the 4matic drive over the RWD.


Cho Baka
Premium,MVM
join:2000-11-23
there
kudos:2
Reviews:
·TekSavvy DSL
Yes, I suppose they use an Adjustable Powerband:
»kalecoauto.com/index.php?main_pa···ts_id=36
--
The talented hawk speaks French.


Insight6

join:2012-08-25
As I am sure you know modern high performance engines in production or passenger cars are chip tuned to impact the firmware of the EMS. The engines normally are detuned to produce less than their maximum power to among other reasons increase the life of the engine and gas mileage. There are, of course, other adjustments or modifications that can be made but that is the procedure that I was specifically referring to in my previous post.

In a high performance V8 the power can be electronically increased to more than compensate for the extra 200 pounds of a 4matic drive in for instance a Mercedes E550. It’s a quite simple electronic adjustment when done by a skilled technician


mob
On the next level..
Premium
join:2000-10-07
Reviews:
·SureWest Internet
said by Insight6:

As I am sure you know modern high performance engines in production or passenger cars are chip tuned to impact the firmware of the EMS. The engines normally are detuned to produce less than their maximum power to among other reasons increase the life of the engine and gas mileage. There are, of course, other adjustments or modifications that can be made but that is the procedure that I was specifically referring to in my previous post.

In a high performance V8 the power can be electronically increased to more than compensate for the extra 200 pounds of a 4matic drive in for instance a Mercedes E550. It’s a quite simple electronic adjustment when done by a skilled technician

It's technically possible to sit a workstation, build a tune and load into an ECU without a dyno for tuning purposes, you'll probably not like the results.

And yes, some ECU profiles are made to increase the service life and reduce operating costs. That being said, when you start dropping $100,000 plus for a car, the chances that an ECU profile update can wring out enough extra power to compensate for an extra 200lb on the vehicle is probably going to happen without upgrades or an additional power adder being installed on the engine are not good.

100lb roughly translates to .1 second in a drag race, so they would have to make the AWD car "faster" just to keep up with the RWD only model, just to stay equal in terms of absolute performance.
--
Ich habe kein Mitleid - Me
You're a daisy if you do. - Doc Holliday
And as always, have nice day.


Insight6

join:2012-08-25

1 edit
reply to Insight6
I finally found a specific response to the specific question of the OP in post #7 in this short thread on the difference between the 4matic and RWD.

»mbworld.org/forums/e-class-w212/···rwd.html

Thanks to all that posted in this thread.


CylonRed
Premium,MVM
join:2000-07-06
Bloom County

1 recommendation

Those responses are pretty much the consensus here - I believe everything mentioned in that thread was mentioned in this one...
--
Brian

"It drops into your stomach like a Abrams's tank.... driven by Rosanne Barr..." A. Bourdain