Autocar: New TT can rival the Cayman in driving dynamics.

[Wolfe]

Actually, I didn't say all FWD based AWD cars are piggish.

They are almost all piggish or ugly though, I.E. the Evo.

And let it be known that the more power an AWD system sends to the rear (no matter what it's based on), the better it performs.

For example, Raghavan, the Evo handles well because its Active Rear Diff. sends power where it's needed most -- the outside-rear wheel.

 

[Onikaze]

^ Just like the Acura RL, the most exciting thing I've seen from Honda since the NSX died.

Now if only they would put that SH-AWD in a Civic SiR or something to make a "pretty good" car into a great one.

 

[Raghavan]

And let it be known that the more power an AWD system sends to the rear (no matter what it's based on), the better it performs.

For example, Raghavan, the Evo handles well because its Active Rear Diff. sends power where it's needed most -- the outside-rear wheel.

Yeah, I'm agreeing with you, but disagreeing with Onikaze's statement.

 

[harrytuttle]

The TT and A3, along with the new Passat and Golf R32 use the Haldex differential, which is FWD until power is needed to the rear wheels. Sort of a 'band-aid' system as I call it. You're basically taking an FWD platform and adding a driveshaft and rear and center diff. And the Haldex center diff is only capable of giving 50% of the power to the rear, and only when it's needed, such as during hard launches, hard cornering, or in the wet.

The old Passat 4 Motion, the dead Phaeton, A4, A6 and A8 all use the Torsen differential. This has a rear bias or 50:50 power split at all times. Not FWD biased, although you can get all those cars in FWD (except FWD versions of the Phaeton, A8 and A6 are only available in Europe). This gives these cars better handling capabilities than the cars with the Haldex center differential.

Ah. Thanks. That information was definitely needed.

And no, you can't set the power between the two axles yourself in AWD systems. Some, you can't really control. Others, like the Haldex, can only send 50% to the rears, and that's computer controlled. The thing is, the rear differential isn't strong enough to take the full engine power, so you'll end up damaging something in the long run. Subaru's AWD system can be controlled, at least in the STI, between 35:50 and 50:50. Others, like the Bugatti Veyron, can transfer power infinite ways, so it can be either FWD, AWD, or RWD.

Uh, actually you CAN set the front/rear power bias: change out the center differential. Not something you can do from the driver's seat, but I get the idea. As for the STI, the dial next to the handbrake doesn't do anything to the front/rear bias. It controls the amount of lockup between the front & rear differentials. The varying rate is controlled electronically & automatically, only locking to 50:50 should you set the dial to "L". Driving one every day, I think I have a good idea on what it does.

The reason Audi cars have been piggish over recent years is not the AWD system (FWD-based or not), but the massive weight they insist on slinging ahead of the front wheels: bi-turbo V6's and large DOHC V8's don't exactly sit well between the wheels. It wasn't until the current generation of A4/S4 that the engine bay was large enough to fit a V engine back far enough to get an appreciable weight balance, and even then it took a severe modification of the AWD bias to get anything resembling a real sports car, and even then it just barely edges out it's competition: a 2001-era M3. Fast, yes; fun, no.

The old Quattros had turbocharged inline-5's, longidtudinally mounted, and they sat very neatly between the front wheels, nice and low. There was also the fact that they were rather lightweight cars, something all of Germany has long since forgotten (911 GT3 RS and M3 CSL aside).

 

[Onikaze]

Yeah, I'm agreeing with you, but disagreeing with Onikaze's statement.

How so?

What exactly is disagreeable about the statement that it is hard to make a FWD car into AWD without making it heavy, and nose heavy at that?

You bring up the Evo, one instance, where a rather small engine, in an already decently balanced car got weight added to the rear, and wound up not piggish.

 

[Raghavan]

How so?

What exactly is disagreeable about the statement that it is hard to make a FWD car into AWD without making it heavy, and nose heavy at that?

You bring up the Evo, one instance, where a rather small engine, in an already decently balanced car got weight added to the rear, and wound up not piggish.

I suppose it's hard... I thougtht you just said that all FWD based AWD cars are piggish.
I get it now.

Uh, actually you CAN set the front/rear power bias: change out the center differential. Not something you can do from the driver's seat, but I get the idea. As for the STI, the dial next to the handbrake doesn't do anything to the front/rear bias. It controls the amount of lockup between the front & rear differentials. The varying rate is controlled electronically & automatically, only locking to 50:50 should you set the dial to "L". Driving one every day, I think I have a good idea on what it does.

You drive an STI? Cool! But I'm not sure if I understand what you're saying, and i still stand by what I said. Here's a quote from Car and Driver:

The Subaru employs an electromagnetic clutch on the center differential. Under normal driving conditions, say you're just cruising down the interstate, the diff clutch is disengaged, and 65 percent of the engine power is routed to the rear wheels, with the remaining 35 to the front (a 35/65 front-to-rear split). The car's engine computer adjusts that center-diff clutch, based on information from the yaw-rate and throttle-position sensors, and can send as much as 50 percent of engine torque to the front wheels. So the Subaru varies the torque split between 50/50 and 35/65. The driver can also manually select the torque split via a center-console switch.

That's what I was talking about. I'm not sure what you're talking about, perhaps you can explain that to me.

The reason Audi cars have been piggish over recent years is not the AWD system (FWD-based or not), but the massive weight they insist on slinging ahead of the front wheels: bi-turbo V6's and large DOHC V8's don't exactly sit well between the wheels. It wasn't until the current generation of A4/S4 that the engine bay was large enough to fit a V engine back far enough to get an appreciable weight balance, and even then it took a severe modification of the AWD bias to get anything resembling a real sports car, and even then it just barely edges out it's competition: a 2001-era M3. Fast, yes; fun, no.

Even the new RS4 has its V8 ahead of the front axle. Very nose heavy, and Audi has compensated for that weight gain by making the front subframe and panels out of aluminum to give it a better weight balance. So much weight in front of the front wheels equals excessive understeer. It doesn't help that the RS4 is over 3,900 lbs either!

 

[GM]

Not bad, looks better than the old one, not a nice interior though.

 

[///M-Spec]

Good looking car. Love the flat bottomed steering wheel.

Rival the Cayman for driving dynamics? I seriously doubt it.


M

 

[YSSMAN]

...Where have we had this FWD versus AWD versus RWD convertation before? Ohh wait, any time any of these setups come into question!

Quite frankly, I don't give a damn if the car understeers or overseers in excess as long as the car feels good to me. Sure, if I'm running around a track all day, I'd want something like an STi or Evo, Elise or Corvette, GTI or Si... But generally speaking, aren't you guys being just a tad picky about a car that really hasen't even gone into full release mode yet?

I'm interested in what the American automotive press has to say about the car, particularly Car and Driver, as I generally place them at the top of my automotive opinions list next to the folks at Top Gear. However, even Mr. Clarkson himself has said that he was pleasantly surprised by the car in comparison to the old one, and that the car somehow manages to be fun to drive even though in his mind, it shouldn't.

The steering has a crackle and a fizz, so you’re left in no doubt it is connected to the road. Likewise the engine makes a muted roar like it wants to be let off the leash and whipped a bit. And when you turn into a corner with your foot off the throttle, what’s this . . . ? Why, it’s the back end sliding round, ever so gracefully. It felt like I was driving Darcey Bussell... I shall stop short of saying I loved the new TT. You can’t love something that looks so similar to something you loathed. But I did enjoy driving it.

 

[harrytuttle]

You drive an STI? Cool! But I'm not sure if I understand what you're saying, and i still stand by what I said. Here's a quote from Car and Driver:

The writer, like most reviewers, didn't get the full story. The console has two bits: A toggle button and a rolling dial. Look here for interior shots:
http://www.subaru.com/shop/overview.jsp?model=IMPREZA&trim=WRX_STI_SEDAN
I hate Shockwave image galleries....

When you turn the car on, the toggle defaults to off. This is echoed by a display on the dash between the fuel & temperature gauges. Pressing the toggle allows you to change the percentage of lockup between the front & rear wheels. You change that percentage (and can see the dash display change) by rolling the wheel forwards or backwards.

This change is really just how much you want to prevent the computer from controlling the torque split. Leaving it "open" or off, the computer is free to do whatever it feels is right, starting from 35:65 (in 2005, 2007 is 41:59), front:rear. Setting it to "locked", it stays at 50:50, helping you get through the snow...provided you don't stick with the otherwise great summer tires.

I can't find a manual for the STI on Subaru's website, but this explains it better:

Symmetrical All-Wheel Drive With Driver Controlled Center Differential (DCCD)

The Impreza WRX STI is equipped with the brand’s most performance-directed Symmetrical All-Wheel Drive system featuring Driver Control Center Differential (DCCD). A planetary center differential provides a performance-oriented 35 percent front / 65 percent rear power split. Set in automatic mode, the electronically managed continuously variable transfer clutch can vary the torque distribution ratio as needed to suit driving and road-surface conditions.

Automatic mode provides the best all-around performance for most drivers and circumstances, varying the front/rear torque distribution automatically depending on driving conditions and driver input. The system determines the ideal power distribution in response to vehicle acceleration, deceleration, steering angle, cornering force and wheel slippage.

In manual mode, DCCD allows the driver to vary the front-to-rear torque distribution (up to 50/50 maximum) to optimize All-Wheel Drive performance for varying driving conditions. The driver first selects manual mode with a console-mounted button and then turns a thumbwheel on the center console to select from among six levels of center differential locking. Increasing the lock factor keeps more power at the front wheels, which the driver might want in certain driving conditions, on particular roads or to suit an individual driving style.

http://www.rsportscars.com/eng/cars/impreza_wrx_sti.asp

You're not changing the percentage directly, but either letting it free or locking it up.

Even the new RS4 has its V8 ahead of the front axle. Very nose heavy, and Audi has compensated for that weight gain by making the front subframe and panels out of aluminum to give it a better weight balance. So much weight in front of the front wheels equals excessive understeer. It doesn't help that the RS4 is over 3,900 lbs either!

Yeah, much as I like safe cars, I don't like heavy cars. You'd think that a company that pioneered much of the modern work with aluminum in road cars would do a lot better, and not be beaten to the punch by Jaguar (bigger, stronger car in 2006 with about 400 lbs less weight). And it will take a major re-engineering of the A4 platform to fix the problem created by the German horsepower wars. Time was, the 1981 Quattro Sport was hardly considered a "pig".

 

[Raghavan]

The writer, like most reviewers, didn't get the full story. The console has two bits: A toggle button and a rolling dial. Look here for interior shots:
http://www.subaru.com/shop/overview.jsp?model=IMPREZA&trim=WRX_STI_SEDAN
I hate Shockwave image galleries....

When you turn the car on, the toggle defaults to off. This is echoed by a display on the dash between the fuel & temperature gauges. Pressing the toggle allows you to change the percentage of lockup between the front & rear wheels. You change that percentage (and can see the dash display change) by rolling the wheel forwards or backwards.

This change is really just how much you want to prevent the computer from controlling the torque split. Leaving it "open" or off, the computer is free to do whatever it feels is right, starting from 35:65 (in 2005, 2007 is 41:59), front:rear. Setting it to "locked", it stays at 50:50, helping you get through the snow...provided you don't stick with the otherwise great summer tires.

I can't find a manual for the STI on Subaru's website, but this explains it better:


http://www.rsportscars.com/eng/cars/impreza_wrx_sti.asp

You're not changing the percentage directly, but either letting it free or locking it up.



Yeah, much as I like safe cars, I don't like heavy cars. You'd think that a company that pioneered much of the modern work with aluminum in road cars would do a lot better, and not be beaten to the punch by Jaguar (bigger, stronger car in 2006 with about 400 lbs less weight). And it will take a major re-engineering of the A4 platform to fix the problem created by the German horsepower wars. Time was, the 1981 Quattro Sport was hardly considered a "pig".

Ahh, I see thanks.

And it's pretty sad when the full size XJR is less than 100 pounds more than the RS4...

 

[harrytuttle]

And it's pretty sad when the full size XJR is less than 100 pounds more than the RS4...

They'll figure it out someday. I like Audi, and I have faith in them.

 

[niky]

What exactly is disagreeable about the statement that it is hard to make a FWD car into AWD without making it heavy, and nose heavy at that?

And what about the heavy BMW x models? And since when does adding weight to the rear end of a car make it any nose-heavier than it is?

But I think harrytuttle said it best... Audi's main problem is their insistence on slinging engines so far ahead of the front axle. Everyone else gets it... shift the weight a little further back, and you can get a 60:40 weight split. Still not ideal, but just a little further and with the right materials, 55:45... as close as you can get with a FWD car.

Now, with more manufacturers putting headers on the firewall side, could they please put the transmission in front?

Now if they fixed that with the TT, I won't be surprised if it handles nifty. But I'm not expecting it to get anywhere close to the Cayman without AWD. A telling factor is that Clarkson drove the 2.0T TT. He'd likely feel a little different in a top-of-the-line TT, with the bigger engine in the nose and the heavier drivetrain. With an FWD car, the model with the smallest engine always feels spry compared to the top-of-the-line models, simply because the weight balance is much better.

 

[Wolfe]

But I think harrytuttle said it best... Audi's main problem is their insistence on slinging engines so far ahead of the front axle. Everyone else gets it... shift the weight a little further back, and you can get a 60:40 weight split. Still not ideal, but just a little further and with the right materials, 55:45... as close as you can get with a FWD car.

They might as well build their cars like the old Sport Quattro, with front and rear overhang that's miles long. Audi's cars could use some "character" anyway.

 

[Onikaze]

I like the idea of the transmission ahead of the engine, go for the wheels to the corner look.

FWD cars could benefit from that, not to mention a Trans is smaller and easier to clear with a swoopy hood than an Engine Block, so you could avoid having to make block ended cars for EU pedestrian protection.