What does everyone think on below info ? I got it off the Porsche Club America site............


911 Turbo Engine

performance specs for 2007 997 turbo
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I recently purchased the new 997 twin turbo, Tiptronic S. There is tremendous acceleration in excess of 3,000 rpm, but acceleration at lower rpm is very slow. Porsche states (per Philip Raby, article in July issue of Total 911, and confirmed directly with him) that the car accelerates from 50 mph to 75 mph in 3.5 seconds in 4th gear (without sports boost active), but after approximately 4 seconds the turbo has reached only about 57 mph. It feels like my Toyota Sequoia. My dealership states that the engine should wear in and provide better performance, but I doubt it will have anywhere near that much of an effect.

I believe the professionals at my dealership do not have much direct exposure to the 997 turbo and understandably cannot provide the answer/solution until they have more experience. In the meantime can you provide some direction, or is there a branch of Porsche that deals with customer questions/issues with new vehicles/systems? I want my dealership to get feedback from Porsche, or let me do so directly.

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When I first bought my 997TT I was thrilled and disappointed at the same time. All the hype of no lag, super fast low end and so on was not there. Given what I came out of I was not surprised by this however I was shocked how the car still had what I considered to be lag as compared to the 996TT. I know, one should not complain especially after the years I have spent in 930s. Heck, I still own one for that matter.

After some testing several things became apparent. The first was the car does need to loosen up. Either the program is set to pull back or the motor is so tight that almost right at 1000 miles the car loosens up and makes more power. Companies are now getting wise and putting timed programs in to pull timing, TB parameters etc. I have not confirmed this but I have compared several 997TTs and they all do the same thing.

The other interesting thing we found was the car carries an enormous amount of back pressure through the exhaust. The new variable turbos do not seems to like back pressure and want it less than the standard turbo. This is robbing the low end and creating what can almost be described as a stutter or drop off up top near read line in sport mode.

The last thing is the there is already another software version with these cars. Whether or not the dealers know the cars have another mapping they are coming out with. This map seems to drastically help across the range.


Stephen Kaspar - PCA WebSite - 1/1/2007

 

Stephen Kaspar = Porsche PhD from Imagine Auto..

IMO.. His word is golden; the man has spent more seat time in Porsches than the whole of Dortmund.

 

Seems like there are more stories of people being dissapointed with there turbos popping up lately. I think there is a misconception though and that is that from an engineers standpoint no lag means that the turbo is compressing air and making boost but from a drivers standpoint it's hard to really feel until about 5-7lbs of lbs are present. So in that aspect I think people who drive turbo cars have to get used to that but for a turbo car you wont find hardly any that kick in like a porsche turbo. As for all the complaints with the 997, I have no answer.

 

I should be careful what I write

 

Is this post 1000-mile power increase real or placebo? I mean I wonder if it is the car "breaking in" or the driver getting more in tune with the car.

I'm curious if anyone has any objective performance date on this.

 

hey stephen,

good to know you are the guru of porsche's.
when was there a software remap ? my car is a november 06 build. its a tip but i dont think the way it pulls is a 3.7 sec 0-100 time. its got 600 kms on the odo now.

it was mentioned before that there is a hold-back programmed into the ecu.....i kind of doubt that.....will go for a 400 km run today to hit the 1000 mark i guess.....

all info most appreciated....thanks.

 

Tiptronic car is very strange.. I have made 5500km. My car is slow in low rpms.. It is not a problem from backpresure as I have Cargraphic's exhaust and cargraphic's Maniford (headers) sets.. (it helped it a little in low but it is still slow)
On the other hand sometimes the car is really fast and sometimes not.. I dont know what is going on.. (it is not the problem with the pedal button that Todd mentioned).Maybe it is a problem with the intercoolers?! With the heat? I dont know what is going on...
I am thinking now to place a modified ECU. But I am really afraid of making my car even worse....

 

It is the program as I have mentioned. If you look at all the dynos I have done the curves have some strange dips in it from the factory. This is what you feel on the road. Sometimes it is better at times then others.

My car is also a 06 build. As far as if the lower power under 1000 miles being in my head, sorry I don't do SOTP dynos. On my car as well as several others tested there is at least a 50HP delta between new and 1000 + miles as confimered through my Mustang AWD dyno.

 

So you believe that if I order a reprogrammed Ecu is it going to fix the problem?! Or it will make it even worse?!

 

If you look at the original curve of the dyno the top end dips are hard after ramp up. Then on the very tail end the car comes up again. The tip of course has the switch problem on top of that. The cars run very hot EGTs and in addition to that the overboost doesn't really seem to stay in boost like it should from 2-5K. It will blip for a second but never seems to sustain. All this is programming because when we change that it stops.

<O</O
The program will not rectify the switch on the tip problem, but if driven in the manner that has been suggested the car will rip and be relieved of these problems. <O</O

 

Are these problems specific to the tip only? Which if any of these problems does the turbo with manual transmission have?

 

The goofy curve and dip is a problem with either car. The downshift in manual mode is a tip only issue. It will not loose HP, but it will loose TQ.

 

Here is the orginal ECU map and then the updated version. Look at the curves! Big difference.

 

so you meant that the software auto-remaps after the 1000 mile break-in barrier ?

whats your take on powerbnraking for acceleration runs from standstill ?

can it harm the driveline.
did a couple of runs. held brake till approx 4,500 rps then let go....
fastest time manually stopped on sports chrono was 4,24 0-100 km.

 

can now you show us a power curve between the good stock and a modified ECU by you plz?! (with headers and Exhaust?!)
These big differences still happen and in modified cars?! Or only on stock?!