M4 vs TRACTION

[brava09]

Originally Posted by dkhm3

Ya, that happens all the time. That's why there are so many people crashing their Ms during street races.

Have you ever driven a turbo rwd car? You a little bit of skill.

I had a 335i for two years before my E92 M3. Both very difficult to put the power down in 1st and 2nd gears. Sometimes even in 3rd gear if road surface was not the best.

[gthal]

Originally Posted by brava09

I had a 335i for two years before my E92 M3. Both very difficult to put the power down in 1st and 2nd gears. Sometimes even in 3rd gear if road surface was not the best.

So why wouldn't everyone drop RWD cars for the Audi? Oh wait, I know...

The RS5 is a great car but you are beating a dead horse here. Not sure why you are this mission but you aren't accomplishing much.

[brava09]

Originally Posted by gthal

So why wouldn't everyone drop RWD cars for the Audi? Oh wait, I know...

The RS5 is a great car but you are beating a dead horse here. Not sure why you are this mission but you aren't accomplishing much.

You got it wrong, I don't care Audi/BMW, all I say is that M4 needs awd to make full use of its power.

However, it looks like the next M5 will be awd, why would they do that? And M3/M4 will follow suit, like it or not. If they make it optional, I can bet my RS5 that most of the sales would go to the awd versions.

I would probably be in a M5 now if it was xdrive, but I'm forced to look after an RS7 for my next car. I don't like the E63 AMG even if it's awd.

[CanAutM3]

Originally Posted by gthal

So why wouldn't everyone drop RWD cars for the Audi? Oh wait, I know...

The RS5 is a great car but you are beating a dead horse here. Not sure why you are this mission but you aren't accomplishing much.

brava09 is...

[M6-Coupe]

Originally Posted by brava09

I had a 335i for two years before my E92 M3. Both very difficult to put the power down in 1st and 2nd gears. Sometimes even in 3rd gear if road surface was not the best.

Originally Posted by brava09

However, it looks like the next M5 will be awd, why would they do that? And M3/M4 will follow suit, like it or not. If they make it optional, I can bet my RS5 that most of the sales would go to the awd versions.

I would probably be in a M5 now if it was xdrive, but I'm forced to look after an RS7 for my next car. I don't like the E63 AMG even if it's awd.

If you really think that 335i or E92 M3 have difficulty to put their power down, then even AWD M5 has the same difficulty for you regardless of AWD. having AWD doesn't mean that car can perfectly put "all it's power" down.
The next generation of M5 will have 600+ HP and will weigh ~4000lb and that's the reason AWD may be offered for this monster...

[brava09]

Originally Posted by M6-Coupe

If you really think that 335i or E92 M3 have difficulty to put their power down, then even AWD M5 has the same difficulty for you regardless of awd
.

I strongly disagree.

[M6-Coupe]

Originally Posted by brava09

I strongly disagree.

LOL. OK
Have you ever driven RS7? How do you feel about putting power down on this car? The next generation of M5 will transfer a lot more torque to the wheels compare to RS7. And why I'm claiming this? because even the current X5M and X6M have over 550 lb-ft torque "on the paper" and they are AWD... you can test drive them. Now consider what a 4000 lb M5 with even the same torque and 1000 lb less weight can do

[brava09]

Originally Posted by M6-Coupe

LOL. OK
Have you ever driven RS7? How do you feel about putting power down on this car? The next generation of M5 will transfer a lot more torque to the wheels compare to RS7. And why I'm claiming this? because even the current X5M and X6M have over 550 lb-ft torque "on the paper" and they are AWD... you can test drive them. Now consider what a 4000 lb M5 with even the same torque and 1000 lb less weight can do

I'll manage to put the power down in the M5 xdrive

[M6-Coupe]

Originally Posted by brava09

I'll manage to put the power down in the M5 xdrive

[Powerslide]

Originally Posted by Falafel Combo

Is this really true? That would be impressive. I remember reading somewhere (fuzzy memory) that power falls off around 5800 rpm?

No worries - the only people who say that are people who don't own an F8x.

I came from an E9x M3 myself - and I took that car up to 8,400 rpm quite a few times (and enjoyed every second of it too)! But anyone who says that the S55 "runs out of breath" at high speed is dead wrong. Objectively - the dynos show constant horsepower peak up to 7300 rpm (which for a turbo is very good - only 300 short of the 7,600 redline). And before the haters get on here and say "well - but the torque drops off after 5700 rpm..." keep in mind that the S55 at 7,600 rpm is still making significantly more torque that the S65 at high rpm's. So even though the torque/horsepower curves of the S55 and S65 are going to be different - a stock S55 is going to have a noticeably faster rate of acceleration at any rpm. Also - keep in mind that the S65's torque curve also begins to drop off significantly before reaching 7,000 rpms.

Subjective experience (over 8000 miles on the F80) completely backs up the objective data above as well. My F80 (bone stock) accelerates like an absolute maniac in the 5500-7400 rpm range - and the decrease in rate of acceleration for those last 200 rpms is barely detectable.

So - for those of you who would rather have an E9X or an RS5 vs. an F80 - absolutely nothing wrong with that opinion - those are both fantastic cars. But misstating facts is a completely different story than having a contrary opinion (and unfortunately is a shockingly common theme on this forum)...

[End rant]...

[dkhm3]

Originally Posted by brava09

You got it wrong, I don't care Audi/BMW, all I say is that M4 needs awd to make full use of its power.

However, it looks like the next M5 will be awd, why would they do that? And M3/M4 will follow suit, like it or not. If they make it optional, I can bet my RS5 that most of the sales would go to the awd versions.

I would probably be in a M5 now if it was xdrive, but I'm forced to look after an RS7 for my next car. I don't like the E63 AMG even if it's awd.

RWD is not going anywhere.

Please read up on the rear engined GT3 and the mid engined 458 Ferrari. and the front engined Z06.

M3/M4's have a long way to go before plateauing RWD performance. I had a 335i. There is no way I'd lose traction on 1st and 2nd unless it was oily and wet.

M5 well, that car is too big and heavy, so you may need the AWD to control all that mass.

You are one stubborn man/woman.

[Alex07M3]

Originally Posted by dkhm3

RWD is not going anywhere.

Please read up on the rear engined GT3 and the mid engined 458 Ferrari. and the front engined Z06.

M3/M4's have a long way to go before plateauing RWD performance. I had a 335i. There is no way I'd lose traction on 1st and 2nd unless it was oily and wet.

M5 well, that car is too big and heavy, so you may need the AWD to control all that mass.

You are one stubborn man/woman.

Do you really compare a rear engine car(GT3), a mid engine car(458) and a car that comes with 335 rear tires(Z06) to an M4 that is front engine and has 275s rears!? :

[Ian1973]

I have 275 supersports on my 335 and it will loose traction in 1st and 2nd easily. Of course once it breaks, then I'm only spinning one tire = bad.

I am tuned though. Stock I don't have much issue with traction.

[Powerslide]

What a lot of people forget is that the whole reason a rear or mid-engined car can have such great traction despite RWD is not because the engine is toward the rear of the car, but more directly because of a greater percentage of weight on the rear wheels. In other words, what determines traction is the ratio of torque relative to the size of the contact patch of the tire and relative to the amount of weight on the drive wheels.

Hypothetically, assume car #1 is a front-engined car with 400 lb/ft of torque at the rear wheels and 2,000 lbs of weight on the rear wheels.

Now - assume car #2 is a rear or mid-engined car with 400 lb/ft of torque at the rear wheels and 2,000 lbs of weight on the rear wheels.

Assuming both cars have the same sized and same type of tires on the rear wheels, both cars will have equal straight-line acceleration traction potential. In other words, the rear or mid-engined car under those hypothetical facts would have no advantage traction wise.

Now - take two more hypothetical cars. Hypothetical car No. 3 has a total weight of 4,000 lbs, is front-engined, has has a front/rear weight distribution of 55/45 front/rear. Also assume 400 lb/ft torque at rear wheels.

Hypothetical Car No. 4 has a total weight of 4,000 lbs., is rear/mid engined, has a front/rear weight distribution of 45/55 front rear, and 400 lb/ft torque at rear wheels.

Under these facts, Car No. 4 WILL have a traction advantage, (assuming both cars have the same rear tires/sizes) NOT directly because it is rear engined, but again - because there is more weight on the rear wheels relative to the amount of torque.

Soooo - where am I going with this? It's the point that RWD cars can still have huge power and still have great traction, as long as a sufficiently high factor of adhesion is maintained. The McLaren 650S and McLaren P1 are great examples - both are turbocharged and make massively more torque that the F8x generation of M3/M4 - oh and BTW - both of those are RWD - NOT AWD!!!

So why are lots of high performance cars going to AWD? Probably because it is cheaper to extract more traction by going to AWD in many cases than optimizing a RWD car with McLaren levels of horsepower and torque (even the LaFerrari is RWD - and that car has waaaaay less weight on its rear wheels relative to the amount of torque/horsepower it is making!! So I do agree that while there is still potential to extract more power/performance from RWD - the affordability of such cars may become a bigger issue relative to an otherwise identical car with AWD... (that's my non-engineering based opinion at least)...

The confusion comes from the fact that assuming two identical cars, if you take the engine and move it to the rear, you'll have a greater percentage of weight on the rear wheels - which WILL give more traction potential.

[Powerslide]

Originally Posted by Powerslide

What a lot of people forget is that the whole reason a rear or mid-engined car can have such great traction despite RWD is not because the engine is toward the rear of the car, but more directly because of a greater percentage of weight on the rear wheels. In other words, what determines traction is the ratio of torque relative to the size of the contact patch of the tire and relative to the amount of weight on the drive wheels.

Hypothetically, assume car #1 is a front-engined car with 400 lb/ft of torque at the rear wheels and 2,000 lbs of weight on the rear wheels.

Now - assume car #2 is a rear or mid-engined car with 400 lb/ft of torque at the rear wheels and 2,000 lbs of weight on the rear wheels.

Assuming both cars have the same sized and same type of tires on the rear wheels, both cars will have equal straight-line acceleration traction potential. In other words, the rear or mid-engined car under those hypothetical facts would have no advantage traction wise.

Now - take two more hypothetical cars. Hypothetical car No. 3 has a total weight of 4,000 lbs, is front-engined, has has a front/rear weight distribution of 55/45 front/rear. Also assume 400 lb/ft torque at rear wheels.

Hypothetical Car No. 4 has a total weight of 4,000 lbs., is rear/mid engined, has a front/rear weight distribution of 45/55 front rear, and 400 lb/ft torque at rear wheels.

Under these facts, Car No. 4 WILL have a traction advantage, (assuming both cars have the same rear tires/sizes) NOT directly because it is rear engined, but again - because there is more weight on the rear wheels relative to the amount of torque.

Soooo - where am I going with this? It's the point that RWD cars can still have huge power and still have great traction, as long as a sufficiently high factor of adhesion is maintained. The McLaren 650S and McLaren P1 are great examples - both are turbocharged and make massively more torque that the F8x generation of M3/M4 - oh and BTW - both of those are RWD - NOT AWD!!!

So why are lots of high performance cars going to AWD? Probably because it is cheaper to extract more traction by going to AWD in many cases than optimizing a RWD car with McLaren levels of horsepower and torque (even the LaFerrari is RWD - and that car has waaaaay less weight on its rear wheels relative to the amount of torque/horsepower it is making!! So I do agree that while there is still potential to extract more power/performance from RWD - the affordability of such cars may become a bigger issue relative to an otherwise identical car with AWD... (that's my non-engineering based opinion at least)...

The confusion comes from the fact that assuming two identical cars, if you take the engine and move it to the rear, you'll have a greater percentage of weight on the rear wheels - which WILL give more traction potential.

Oh - and one more example - the Mercedes-AMG GT - front engined, turbocharged, RWD - over $130,000, and a lot more torque at the rear wheels - so don't write off RWD yet... even if turbocharged and front-engined!!

[M6-Coupe]

Originally Posted by Powerslide

Oh - and one more example - the Mercedes-AMG GT - front engined, turbocharged, RWD - over $130,000, and a lot more torque at the rear wheels - so don't write off RWD yet... even if turbocharged and front-engined!!

Yes it's RWD... and also has 47/53 (front/rear) weight distribution and lower center of gravity in addition to the position of driver's seat which is more biased toward the rear

[BOOstJunkee]

This may have been stated, but I have not read through this entire thread....

What is the widest tire a M3/4 can run without any modifications to the car?

[M6-Coupe]

Originally Posted by BOOstJunkee

This may have been stated, but I have not read through this entire thread....

What is the widest tire a M3/4 can run without any modifications to the car?

with 10" width (rear), 295
with 9" width (front) , 275

[dkhm3]

Originally Posted by Alex07M3

Do you really compare a rear engine car(GT3), a mid engine car(458) and a car that comes with 335 rear tires(Z06) to an M4 that is front engine and has 275s rears!? :

Are you tarded?

I am saying that M3/M4 has a long way to go before it is has reached full potential for RWD.

I am responding to the other loon that stated m3/m4 needs to be AWD to control all that torque.

[Alex07M3]

Originally Posted by dkhm3

Are you tarded?

I am saying that M3/M4 has a long way to go before it is has reached full potential for RWD.

I am responding to the other loon that stated m3/m4 needs to be AWD to control all that torque.

Nop, completly sane!

I know who you were responding to, and I kind of agree with him on the fact that M3/M4s would benefit greatly from an AWD system, at least optionnal, specially for guys like me who lives with cold weather half of the year! I prefer to have more grip then not enough, and many people are like me, that's why BMW gives AWD to the M5.

[Vectors2final]

How much do your wheels weigh, Alex? Curious.

[dkhm3]

Originally Posted by Alex07M3

Nop, completly sane!

I know who you were responding to, and I kind of agree with him on the fact that M3/M4s would benefit greatly from an AWD system, at least optionnal, specially for guys like me who lives with cold weather half of the year! I prefer to have more grip then not enough, and many people are like me, that's why BMW gives AWD to the M5.

Read the original posts again, the issue was not wet weather, it was traction at all times.

The issue was also if the M3/M4 cannot handle it's torque because it cannot maintain traction.

Explain to me: why is it a car that is the fastest in its class around the 'ring- that consistently beats out all other Audi AWD in its class, have traction issues?

Here are the facts:

M3/M4: 7:52
M5 COMP: 7:54
RS5 7:59
RS6: 8:05

http://fastestlaps.com/tracks/nordschleife.html

Please check other tracks as well, it is basically the same result.

You are trying to compare a Sports sedan/coupe right? SPORT is emphasized.

Audi has shown that it can make more horsepower, and have AWD, and be slower around a track. Give it up for Audi!