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Reviews and Road Tests
First Drive: Audi TT DSG
By by: Jamie Vondruska
Feb 27, 2003, 03:28

Audi's TT finally gets a pair. An extra pair of identical pistons to be exact and oh what a difference those little pistons make in an already fine coupe. More importantly though is the revolutionary racing-derived transmission connected to this engine called Direct Shift Gearbox or DSG for short. The combination of the 3.2l VR6 and DSG may forever change the way you think about alternative transmissions.

This is Audi's first foray with a VR6 powerplant and the new 3.2l is a honey. With 250hp and 236 lb-ft. of torque this new VR6 is deceivingly quick. The VR6 has its cylinders splayed at an angle of 15 degrees, creating a very compact package something of utmost importance in this application since there is very little room under the hood for a six-cylinder. Roller cam followers with hydraulic adjustment are utilized reducing valve rotation friction. In order to reduce emissions and further improve efficiency, the inlet and exhaust camshafts are continuously adjustable. The compression ratio is a high 11.3:1 which means adding an aftermarket forced induction system (for those brave enough to consider it) will be tricky.

Other technical details such as the variable intake manifold and the modified intake ports help give the 3.2l VR6 healthy torque and power output, coupled with low emissions. According to VW and Audi a great deal of detail work has been invested in the area of the cylinder head and air intake components in order to improve peak output and torque characteristic for use in the TT.

What all this technology means is that Audi was able to squeeze a 6-cylinder into the space required by some 4-cylinder power plants. Not only that, but one of the sweetest sounding six-cylinders produced, especially with the new dual-chamber exhaust system fitted on the TT 3.2. This new exhaust has a vacuum activated flap that will open and close depending on exhaust pressures producing a mean roar during wide open throttle and quieting down to a barely noticeable hum when you are light on the throttle. All-in-all a nice way to keep the car quiet during highway cruising but giving the option to dip into the throttle whenever you want to be reminded of what lurks under the hood.

On the road the 3.2l VR6 is extremely flexible with lots of grunt throughout the rev range. The VR6 really shines at 4,000 RPM and above though where the combination of audible and sensory overload conspire to find a way to get you in serious trouble. The 3.2l VR6 is the smoothest VR6 yet and will purr quietly at idle around town or scream at high-revs up in the hills. Audi quotes a 0-62 mph time of 6.4 seconds which is likely on the conservative side based on our drive in the car. What really makes the VR6 shine though is one of the most significant transmissions ever put into a production car - Volkswagen's new Direct Shift Gearbox.



First off, DSG is not a standard automatic transmission by any stretch of the imagination. DSG is something that has never been offered in production vehicles before and is a direct result of racing technology from 20 years ago coming down to consumer levels. Volkswagen has applied for numerous patents on this transmission and has plans to implement it as a third transmission choice in nearly every automobile model they offer in the future, even replacing tiptronic in some models like the Audi A3 or GTI. So you can expect to find DSG along side a manual six-speed in the next Golf V GTI and Audi A3/S3 models for example. VW is even offering DSG in their new Touran MPV and in TDI models in Germany.

Looking at the photo of the shift gate below you can see that at first glance it appears to look just like a regular tiptronic transmission with standard P,R,N and D plus an added "S" for sport mode with a gate to the right for manual shifting. "D" and "S" are both automatic modes much like an automatic transmission however they are drastically different in character - almost like having two different transmissions in the car.

Put the DSG in "D" and it behaves just like a regular automatic for the most part except that at a stop the car goes into neutral. When you start to ease off the brake, the clutch will smoothly engage just like a manual transmission. The current DSG programming for the "D" setting is conservative and shifts up through the gears very quickly if you are driving sedately around town to keep the fuel consumption reasonable. This may seem like a bad thing, but the transmission can make a 6th gear to 2nd gear change in .9 seconds - so when you put your foot down the transmission downshifts RIGHT NOW and immediately into the power band (and rev matches which is trick sounding with the 3.2l VR6). Normal upshifts are unbelievably quick and smooth with no jerkiness.

Drop the transmission in "S" for sport mode and you'll feel like you just swapped out the entire transmission with a complete race setup - the engineers that programmed this mode must really love to drive hard. The sport mode is still an "automatic" mode until you click one of the paddles. However it is very aggressive as it always tries to keep the car on boil between 4000 RPM and redline - imagine driving around like that all the time and you can see why it has its practical limits. Shifts are still VERY smooth between gears (almost too smooth in our opinion, but VW and Audi say they are looking into adjustments) and the transmission keeps the revs in the optimum power band. This setting is so hard core that it is really only useful for track events and driving on very twisty roads.

In sport mode the transmission utilizes fuzzy logic in the programming and is scary in how well it seems to anticipate your need to downshift - enter a straight-away, wind it out to redline, upshift and as you come into the next turn the transmission will rev-match and downshift into the meat of the powerband right about the time you want to down-shift. Since the computer already knows all the optimum shift points to keep the engine in the power band, the DSG will likely out-smart the driver. If you leave the transmission in "S" mode and don't touch the paddles, it will shift up and down through the gears automatically. At any time you can click the paddles and the transmission will assume you want to shift yourself from now on. And it will wait for your shifts - on the cars we drove you could bog it to death or run it clear into the redline and the DSG obeyed your command.



At a basic level DSG is a dual-clutch electronically controlled transmission that can be shifted manually via the shift lever or paddles on the steering wheel or it can be dumped into drive and used like an automatic - there is no clutch pedal. DSG utilizes 2 clutches, 2 main input shafts and 2 sets of gears - 1st, 3rd, 5th and Reverse on one shaft and 2nd, 4th, and 6th on the other. Because this is a wet system, there is an oil coiler and oil filter attached to the transmission.

DSG is completely different from BMW's SMG and Ferrari's F1 system in that it has two clutches instead of one. This means that DSG can fire off an upshift in .008 seconds whereas BMW's SMG takes .8 seconds to make the same shift.

Here's how it works (try to stay with us here): At a stop, the transmission drops into neutral. When you start to lift your foot off the brake, the clutch connected to input shaft 1 will smoothly engage moving the car forward much like a manual transmission except electronically and automatically. Input shaft 1 is now controlling first gear providing power to the wheels. While input shaft 1 is in first, input shaft two has selected 2nd gear in anticipation of the next upshift. When the transmission requests 2nd gear (either via the paddles, gate or automatically) clutch one opens up and clutch two engages in as quickly as .008 seconds. There is a certain amount of slippage in the clutches to ensure a smooth transition from gear to gear. In the event of a downshift, the transmission will request a throttle blip from the engine ECU to match revs and then shift down a gear - this happens in as quick as .6 seconds including the throttle matching. The transmission can even shift from 6th to 2nd gear without having to sequentially run down through every gear. In this case, DSG will switch input shafts from 6th gear going to 5th temporarily on input shaft 2 and then into 2nd with input shaft 1 while blipping the throttle to match revs - all in less than .9 seconds. Got that? Good.

The entire system is electronically monitored and controlled via a mechatronics module inside the transmission. This module communicates with the engine ECU and other electronic systems as well.



If you look at the photo above, you can see shift paddles on either side of the steering wheel along with what looks like a standard automatic/Tiptronic shift gate. The paddles are physically connected to the back of the wheel itself, not the steering column. That way they are always at the 9 and 3 o'clock positions. The left paddle is for down-shifts, the right paddle up-shifts. They are mounted close to the surface of the back of the steering wheel, have a very positive feel and have a very short and precise travel. Also, the R32 paddles are slightly larger and made of brushed aluminum, whereas the Audi TT paddles are black plastic and smaller.

Lastly, VW and Audi engineers have included a launch control feature - put the transmission in "S" mode, turn off the Electronic Stability Program (ESP), hold the brake pedal down with your left foot and floor the gas. The revs will rise to around 3,000 RPM and then quickly remove your foot from the brake pedal and the car will chirp the tires and launch HARD as if you revved a manual transmission and dropped the clutch. Pretty darn cool and a sure fire way to nail those stoplight launches.

The torque rating of the DSG transmission in the TT 3.2 and VW R32 is 325 newtons meters or 240 ft-lb - right about the torque rating of the 3.2l VR6. The DSG transmission weighs about 66 lbs. more than the standard manual MQ350 six-speed. However that includes an oil cooler, ECU, two clutches and more so it isn't exactly an apples and oranges comparison.

DSG utilizes a lot of components from the new six-speed MQ350/02M350 transmission including gears, syncros, sliders and more. DSG maintenance intervals have not been finalized, but it looks like a fluid and filter change about every 45,000 miles.





Clutches are basically not upgradeable because there isn't any room in this particular transmission case. The TT 3.2 and Golf R32 use the highest torque rated DSG (currently) for the Golf IV platform. There are two variations of the DQ250 (internal name for the DSG) that have been set up with lesser mechanicals for lower torque rating applications. Those lower torque rated DQ250 transmission could be upgraded with the TT 3.2/R32 box internals, but the TT 3.2/R32 DSG box is the highest torque rated DSG for the Golf IV platform at this point (and likely for the rest of the Golf IV product lifecycle). Because the DSG is fully electronic, and match-revs downshifts for example, it is tied into the vehicle electronics (including the engine ECU) quite a bit which brings us to the next issue...

While you might be able to get away with minor power upgrades to a TT 3.2 or Golf R32 (intake, chip tuning, exhaust) equipped with DSG, electronic protections and a maximum torque rating of 240 lb-ft will make adding a forced induction system or any other heavy duty power upgrades extremely difficult to impossible. The DSG has what is referred to as micro-slippage in the clutch plates that is constantly monitored by the DSG ECU. If an aftermarket supercharger for example is added to the 3.2l VR6 with a DSG transmission, the additional torque will force that micro-slippage beyond normal tolerances. When this happens, the DSG communicates back to the engine ECU and dials back timing and/or engine revs to try and correct for the "problem" it is seeing.

The natural assumption is that someone in the aftermarket will simply find a way around this and may attempt to change the programming of the transmission. It has taken VW and Audi a long time to get all the programming dialed in on this transmission and it would reportedly be an extremely daunting task to try and manipulate it successfully. Then, even if you did find ways around the built in protective measures, the transmission mechanicals are only designed to handle 240 lb-ft. of torque with no real way to upgrade internals. This means the transmission could likely overheat and shut down till it is back within proper temperature ranges and/or it will simply frag to pieces. So for those that want to add a supercharger or turbocharger to the TT 3.2 or Golf R32 you may want to opt for a manual transmission if it is available here.

In impromptu testing, a DSG equipped R32 on hand went 0-60 in 6.3 seconds without launch control - so it is faster than the manual transmission equipped R32 0-60 times. Gas mileage is better than the manual transmission as well. Our Audi TT scooted to 60 in around 6.2-6.3 seconds as well without launch control so we think it is capable of better times.



We spent nearly 4 hours going up and down the Los Angeles Crest Highway which is loaded with elevation changes and winding roads that are a challenge to drive quickly. The TT 3.2 has far more direct and precise throttle response compared to the regular 1.8T TT models producing better overall feel when apply power - push the throttle and you get instant response. And while we expected the added weight of the 3.2l VR6 hanging off the front end to negatively impact handling, the TT behaved neutrally through most corners giving way to understeer at more than 9/10ths. Lifting off the throttle mid-turn tightens the line and lessens understeer conditions however coaxing the back end out proved to be difficult. These improvements are attributable to stiffer springs rates, uprated shock valving and larger anti-roll bars front and rear on the TT 3.2. The upgraded 13.1 inch brakes borrowed from the RS4 were fade free throughout our very aggressive usage up in the mountains.

After a whole day of aggressive driving we (surprisingly) didn't miss having a manual transmission one bit, in fact DSG proved to a LOT of fun. The 3.2l VR6 sounds are intoxicating with the stock exhaust tuning and the match-revs on downshifts are better than anything we are humanly capable of. Plus as an added bonus you can simply dump the transmission in "D" and not worry about shifting if you run into stop and go traffic like we did on the way home.

Outside of the wonderful new mechanicals, the exterior receives some subtle yet affective enhancements with a newly designed rear wing, new straked intake vents just in front of the front wheels, new honeycomb panel on the rear bumper and revised grill and "titanium" finished headlamp surrounds. Inside you'll find brushed aluminum accents around the DSG shifter and steering wheel mounted paddles. A new instrument cluster with a higher top speed rounds out the changes.



Conclusion

Overall the TT 3.2 is a very worthy addition to the TT lineup. While on paper the 0-60 times don't look that impressive, it is important to remember the total package here and that gearing has been set up for the German market where going 150mph is important. This car really shines on the highway where massive acceleration is just a dip into the throttle away. The 3.2l VR6's sweet sounds and wonderful tractability make it a great powerplant by any measure. DSG is something you *have* to drive to really appreciate and could quite possibly give you pause to consider dumping that manual slushbox. It is that good. The Audi TT 3.2 will be available later this year in the U.S. and current rumors suggest it will be available with either a six-speed manual or the DSG transmission. Pricing has not been announced. Do yourself a favor and give this new transmission a try - you'll be glad you did.



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