Drove AWD and RWD back-to-back
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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.
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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....
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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
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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.
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Wider tires does not mean more resistance to wheel spin.
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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
Last edited by domino_z; Jun 11, 2015 at 10:53 PM.
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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.
How close we are I don't know ...
MC
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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...
Your tyres will be toast though...
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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!
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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.
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.
Last edited by Arne; Jun 13, 2015 at 10:44 AM.
This.... this right here is my issue. This is why i keep saying the whole thing is opinion based. 90% of people on this site say the same thing... "Well $hit... if you want to have fun in this car you have to get the RWD version. No one ever had more fun in an AWD car than a RWD car!"
Overpowered RWD cars aren't fun to me. I had an overpowered 135i and it was simply boring by comparison. I have no interest in drifting, and couldn't give a damn about lap times. I love that feeling when you get thrown back into your seat from the torque and being able to use all the power all the time. You can't use 550 hp in the RWD F Type on the street until you're doing well over the speed limit and that's a significant negative to me. I have much more fun using all that power in 1st, 2nd and 3rd gear through the twisties and flooring it away from a stoplight in my AWD car than I ever could in a RWD equivalent. Sure I rarely hit over 75 mph, but i'm enjoying the hell out of it.
This is my opinion, and others (obviously few of them) share it too... so don't just say the only way someone can have fun is in a RWD car. It goes both ways and there will never be a right answer so we should just all stop debating it. Lap times are one thing, but what's more fun is an irrelevant topic.
Overpowered RWD cars aren't fun to me. I had an overpowered 135i and it was simply boring by comparison. I have no interest in drifting, and couldn't give a damn about lap times. I love that feeling when you get thrown back into your seat from the torque and being able to use all the power all the time. You can't use 550 hp in the RWD F Type on the street until you're doing well over the speed limit and that's a significant negative to me. I have much more fun using all that power in 1st, 2nd and 3rd gear through the twisties and flooring it away from a stoplight in my AWD car than I ever could in a RWD equivalent. Sure I rarely hit over 75 mph, but i'm enjoying the hell out of it.
This is my opinion, and others (obviously few of them) share it too... so don't just say the only way someone can have fun is in a RWD car. It goes both ways and there will never be a right answer so we should just all stop debating it. Lap times are one thing, but what's more fun is an irrelevant topic.
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.
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From: Metrowest Boston
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.
The different shape of the tire patch may affect lateral handling vs straight acceleration.
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.
The different shape of the tire patch may affect lateral handling vs straight acceleration.
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.
Last edited by spegor; Jan 25, 2022 at 02:09 AM.
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