I had an overpowered rwd SLK55 AMG. It was fun at first but got old quick, especially for my wife, every turn does not need to be an adventure. All 3 of my Audi TT's were quattro and it did not affect fun factor, they were full time awd! I'm more curious about active awd. I didn't get the Maserati with it and don't drive it in any way that might have made a difference. I would think the diff on the V8's would make a big difference even over the diff on the S. I would probably want a V8 awd after my AMG experience. Not sure on V6S.

 

your comment about the AMG is interesting...the new AMG GT S has 500+ HP but they choose to keep it RWD. As well as the new crop of Ferrari 488, McLarens 650. But Porsche and Audi with their Turbo and R8 have been AWD....

 

The 650s has a very sophisticated traction control system (they are pretty good in the wet) and doesn't need an AWD system. Having engine behind driver helps as well.

Wonder what the new AMG GT drives like...

Corvettes have always been RWD and the new Z06 has 650 HP albeit with massively wide rear tires and stability control.


MC

 

That's my point, there are still big HP/torque cars that go the RWD instead of AWD, even though I imagine AWD in those cars (AMG GT, Z06, etc.) would help greatly put down the power. Is RWD just a losing battle? I do think eventually all cars will be AWD. But until then, there's still enough love for RWD.

 

Wider tires does not mean more resistance to wheel spin.

 

Couldn't agree more LOL - (exhibit 1) my ZR1 tires at 8500 miles

 

not quite, audi use a haldex setup

transverse engine in the TT means it was full time fwd, and sends a percentage of power to rear when fronts slip - the newer haldex setups are getting better at predicting when to apply rear power for a more neutral feel

'quattro' is merely a marketing term these days and does not apply to any of their road cars

for proper full time centre diff awd cars think evo's and wrx/sti's

 

No but oversteer is reduced.


MC

 

Agreed. As HP numbers keep going up at some point we are going to reach the limits of maximum traction from two wheels. (I wonder what the Hellcat drives like)

How close we are I don't know ...


MC

 

Hi guys.

 

Switch your Traction Control off, and plant your foot in 2nd gear. If you get all the way down and keep it there you will achieve something close to the stated Torque and Power figures from the engine, with some Torque Multiplication at the wheels.

Your tyres will be toast though...

 

All 3 of my TT's were 45-55 full time . Last was a '08 3.2. They went to 50-50 and then 55-45 on various models as years passed,even 40-60 on some RS's but none were active! Don't know about new models but from what I read quattro is still true!

 

All TT versions (and A3 and several VW models as well) had and has different generation of Haldex awd. It's called quattro by Audi and 4-motion by VW.

They are basically fwd with a Haldex coupling that shifts power to the rear when needed (much like the awd F-type is basically rwd that shifts power to the front when needed).

On other Audi models with "real" Quattro, it is a Thorsen coupling that makes the awd system. That system has a much more rear biased set up and is very different system than the Haldex.

The only VW model that uses Thorsen Quattro is the Touareg (which shares the driveline with Porsche Cayenne and Audi Q7).

I have had 2 different model TTS with the Haldex awd and resently a Touareg with Thorsen awd and knows both systems very well. A few years back I even was in direct contact with Haldex (a Swedish company) regarding some detailed questions of the different Haldex generations that was used on the different generations of the TT's (to learn about the differenses) - which basically is:

TT Mk1 has a "reactice" awd system, which means that the power is shiftet towards the rear when front wheels loses traction.

TT Mk2 has a "proactive" Haldex system that shifts power towards the rear as a result of throttle and steering input, so it will react quicker and before the front loses traction, resulting in a less understeered car.

 

i think you should be getting a tesla

 

wider tire = more surface contact = more surface area for static friction force to work agains = takes more force to break the static force threshold and taking it to the lower value kinetic friction force (less acceleration). In non engineering words. Wider tires = more resistance to wheel spin.

 

The contact patch should have the same overall area, regardless of tire width. A wider tire will have a narrower front-back contact patch. The area of the contact patch is primarily a function of the weight of the car and the tire pressure.

The different shape of the tire patch may affect lateral handling vs straight acceleration.

 

Larger tyres mean slower acceleraton and more grip.
If the contact area is the same, as you state, you have not any advantage in road holding with larger tyres. It sounds a bit odd.

 

You guys do know this thread was from 2015 lol

 

Yeah, but I hate misinformation. Just hope I'm not adding to it...