PDK vrs DCT

[SenorFunkyPants]

I had a 997 with PDK on loan for the day and it was interesting to compare that transmission with the DCT in my M3.
Short version - the DCT wins and quite easily.
The PDK seems to shift slower, its not as smooth during the gear change, there is minimal auto blip downshift and the low speed gear chatter makes it sounds like a coffee grinder if you let the revs drop too low....oh and it has the worst most counter intuitive gearchange system know to man - who ever thought that it would be a good idea to make pulling the gear lever back = a downshift!!!!
In Drive it lagged (just like the DCT did before the last software update) when slowing down in 2nd at low revs when I pressed the accelerator, it took about a second to shift into first then about gave me whiplash as it took off down the road...after that I stuck to shifting manually.
The DCT is a proper gem by comparison.

[mkoesel]

Interesting findings SFP. I think this should be in the M3 vs. section though.

The press seems to like PDK other than the funky shift interface you mentioned. I think they are changing that for next year, right?

[FStop7]

That's interesting, the video on GTboard comparing M3 DCT vs. 997S PDK has the Porsche just walking away... That says to me while PDK isn't as refined, it's got a performance advantage.

[mixja]

Originally Posted by SenorFunkyPants

I had a 997 with PDK on loan for the day and it was interesting to compare that transmission with the DCT in my M3.
Short version - the DCT wins and quite easily.
The PDK seems to shift slower, its not as smooth during the gear change, there is minimal auto blip downshift and the low speed gear chatter makes it sounds like a coffee grinder if you let the revs drop too low....oh and it has the worst most counter intuitive gearchange system know to man - who ever thought that it would be a good idea to make pulling the gear lever back = a downshift!!!!
In Drive it lagged (just like the DCT did before the last software update) when slowing down in 2nd at low revs when I pressed the accelerator, it took about a second to shift into first then about gave me whiplash as it took off down the road...after that I stuck to shifting manually.
The DCT is a proper gem by comparison.

Was the 997 in Sport+ mode? In this mode the gear changes are apparently very quick...

[SenorFunkyPants]

Originally Posted by FStop7

That's interesting, the video on GTboard comparing M3 DCT vs. 997S PDK has the Porsche just walking away... That says to me while PDK isn't as refined, it's got a performance advantage.

Firstly I will declare my interest as a long term Porsche enthusiast - I've owned 8.
Its terms of the 997 C2S (385hp) with PDK, it didn't feel any quicker than my DCT M3. It seems a little short of torque at low revs, then comes on strong but hits the soft limiter about 1000? rpm earlier than the M3.
I'm not saying that the 997 C2S isn't faster than the M3, it may well be, but it just doesn't feel it, especially as you have to shift earlier in the 997.
The biggest difference in the cars is just how much more refined the M3 is than the Porsche.

[SenorFunkyPants]

Originally Posted by mkoesel

The press seems to like PDK other than the funky shift interface you mentioned. I think they are changing that for next year, right?

Yes - the new Gen 2 997 turbo will have paddle (+ -) shifters as a no cost option (at least for the UK market)....don't know if it will be a range wide option, but I wouldn't have a PDK car without it.

Originally Posted by mixja

Was the 997 in Sport+ mode? In this mode the gear changes are apparently very quick...

I think that is available in the UK as part of the "Sport Chrono" option pack along with launch control....my demo car didn't have this option.

[urbo73]

The PDK without Sports Chrono is not a good test at all. Sport is the setting to use for PDK - with Sport+ only for real aggressive use. Without Sports Chrono, PDK is as you say, but Porsche made it for performance not smoothness. Evident by the 2-1 downshift in AUTO mode when coming to a stop. It could easily "feather" the clutch and skip that, for a more comfortable ride, but it chooses not to on purpose to save the wear and tear. The C2S will always feel more raw than the plush M3...Not sure I get that point...M3 is soft, not refined. By design.

[sam.k]

http://www.caranddriver.com/reviews/...mparison_tests

[mPlasticDesign]

Not surprised one bit!

[Koroush]

Originally Posted by ///Metak

Not surprised one bit!

///M POWER

[FStop7]

Here's the video I'm referring to.

[JCtx]

PDK is the basically the same as DCT, if not the same; I believe both are Getrag units. The ZF is an 8-speed unit.
I believe each company (Porsche and BMW) does their own tuning, so can't attribute that to the tranny. And the car with the better power to weight ratio, better traction, etc. should perform better; the difference between 2 dual-clutch trannies should be negligible.

[footie]

Originally Posted by SenorFunkyPants

I had a 997 with PDK on loan for the day and it was interesting to compare that transmission with the DCT in my M3.
Short version - the DCT wins and quite easily.
The PDK seems to shift slower, its not as smooth during the gear change, there is minimal auto blip downshift and the low speed gear chatter makes it sounds like a coffee grinder if you let the revs drop too low....oh and it has the worst most counter intuitive gearchange system know to man - who ever thought that it would be a good idea to make pulling the gear lever back = a downshift!!!!
In Drive it lagged (just like the DCT did before the last software update) when slowing down in 2nd at low revs when I pressed the accelerator, it took about a second to shift into first then about gave me whiplash as it took off down the road...after that I stuck to shifting manually.
The DCT is a proper gem by comparison.

Are you sure you drove a PDK because every comment you made about it was the total opposite from mine and every other roadtesters opinion.

Lag, there is none, it was the first thing I went looking for. Shift speed, every bit as quick as DCT. Blipping on downshift, the PDK gives just the right amount to make it smooth, unlike what I found DCT to be like in S5-6. Also in auto mode the thing worked a dream, just like the DCT did except it didn't suffer the lag that was every present in my DCT.

I'm struggling to understand how we both came to totally different conclusions.

[footie]

Originally Posted by elp_jc

PDK is the basically the same as DCT, if not the same; I believe both are Getrag units. The ZF is an 8-speed unit.
I believe each company (Porsche and BMW) does their own tuning, so can't attribute that to the tranny. And the car with the better power to weight ratio, better traction, etc. should perform better; the difference between 2 dual-clutch trannies should be negligible.

Porsche use ZF for their DCT. But I believe they use the same fluid in their gearboxes.

[devo]

Originally Posted by footie

Are you sure you drove a PDK because every comment you made about it was the total opposite from mine and every other roadtesters opinion.

Lag, there is none, it was the first thing I went looking for. Shift speed, every bit as quick as DCT. Blipping on downshift, the PDK gives just the right amount to make it smooth, unlike what I found DCT to be like in S5-6. Also in auto mode the thing worked a dream, just like the DCT did except it didn't suffer the lag that was every present in my DCT.

I'm struggling to understand how we both came to totally different conclusions.

Have to agree 100% with you Footie.

The above C&D road test is so lame. It compares a base Carrera without one of PDK's best features, Sport Chrono, against the M. Hey, if it's a price comparison, so be it, just equip the Carrera with the required options.

Also, the second video is indicative of what the .2 C2S does to the M.

[niqui]

Originally Posted by footie

Are you sure you drove a PDK because every comment you made about it was the total opposite from mine and every other roadtesters opinion.

Lag, there is none, it was the first thing I went looking for. Shift speed, every bit as quick as DCT. Blipping on downshift, the PDK gives just the right amount to make it smooth, unlike what I found DCT to be like in S5-6. Also in auto mode the thing worked a dream, just like the DCT did except it didn't suffer the lag that was every present in my DCT.

I'm struggling to understand how we both came to totally different conclusions.

everything i have read puts the pdk above the dct...

[footie]

Originally Posted by devo

Have to agree 100% with you Footie.

The above C&D road test is so lame. It compares a base Carrera without one of PDK's best features, Sport Chrono, against the M. Hey, if it's a price comparison, so be it, just equip the Carrera with the required options.

Also, the second video is indicative of what the .2 C2S does to the M.

What a C2S Mk2 with PDK does to a tuned M.

[urbo73]

Originally Posted by sam.k

http://www.caranddriver.com/reviews/...mparison_tests

Not only is this guy's voice annoying, but why does the M3 "win"? A real, real lame test. With PASM and SC, you can remap throttle, change PDK shift times/limits, and change suspensions settings in much the same way you can on the M3 (but different). So I don't know what "win" means. I guess the guy couldn't handle the C2 and went off track, which is why he says the M3 keeps you on track LOL. Fool..As if that has anything to do with PDK/DCT...

PDK's clumsy button layout is worse, true, but that's changing starting with the '10 Turbo paddle wheel option. PDK is also a proven system on track. I don't have much experience with DCT (have driven two Ms with DCT but only on street), but I doubt it can be better in any way than PDK - a system born 25+ years ago, albeit used on the 962s in a limited way. Anyhow, like I said, Sports Chrono is a MUST in a PDK equipped car. See my note about the 2-1 downshift too..

[mkoesel]

Originally Posted by devo

...a base Carrera without one of PDK's best features, Sport Chrono, against the M.

Which is why I don't understand why the package - or at least the specific feature(s) of the package that make the car actually perform like it should - is optional. If you replace the M3 in the C&D video with one that has absolutely no options except M-DCT, I'll bet it performs identically to the one they tested. Well, other than that the C&D driver might not be able to keep the car on the track due to no MDM. The Porsche, on the other hand, seems to require Sport Chrono package just to be able to live up to its potential.

[urbo73]

Originally Posted by niqui

everything i have read puts the pdk above the dct...

[urbo73]

Originally Posted by mkoesel

Which is why I don't understand why the package - or at least the specific feature(s) of the package that make the car actually perform like it should - is optional. If you replace the M3 in the C&D video with one that has absolutely no options except M-DCT, I'll bet it performs identically to the one they tested. Well, other than that the C&D driver might not be able to keep the car on the track due to no MDM. The Porsche, on the other hand, seems to require Sport Chrono package just to be able to live up to its potential.

Is EDC standard?....I have to get the package for $3250 to get MDM and EDC. Sports Chrono is $1320 if getting PDK for looser PSM (similar to MDM), etc. It's all marketing. The guy is just yapping and he talks about EDC...Is that needed for DCT? No. But what the heck is he talking about? In the end he doesn't talk much at all about PDK or DCT, which is why the review is L A M E !

[mkoesel]

Originally Posted by urbo73

Is EDC standard?....

No, but as I recall it, back in late 2007 there was a test that compared an M3 with and without EDC and track times were near identical.