oceancarrera

If you buy a 'Porsche certified' used one how does the dealer know if it had a tune?
How does Porsche know if a used one had a tune?
I think it was someone here that had a PDK issue of some sort with the replacement, instead those fools at the dealer tried to fix it.
Conclusion: Once the check clears, Porsche decides who wins and who looses.

ipse dixit

It's recorded in the ECU. A simple reflash by the tuner will not erase the historical data (i.e. the HP/TQ that the car was putting out when you were drag racing the car, or the extra boost (psi) the car was spitting out)

///M3THOD

I can't believe some of the negativity in this thread. It would think regardless of your position on tuning, its exciting to see the potential of this motor with very basic tune.

Does that exhaust sound stock? It sounds a little more aggressive to me, the tuned test car may have an exhaust on it as well. It very much looks like the SpeedTech development car in their videos. At 1:53 in the video you can see the profile of the exhaust.

LavaGTS

I seriously don't get it either. Maybe its a Porsche or 991 thing? I'm new to these cars, who knows.

You made several good points there. I also noticed the exhaust sound but attributed the sound (exhaust rushing/whooshing) to more pressure from the turbos. Now that you mention it, it does look like the speedtech car. Sill sounds rather mild for an exhaust IMO but it's hard to tell with all the video editing.

John D II

Good eye! That is the SpeedTech Exhaust development car in action. It has our Hi-Flow Cats and valved PSE Switch X-Pipe, along with the GIAC tune. The performance difference is the result of the SpeedTech exhaust with our hi-flow cats and the tune, all working together.

LavaGTS

Thanks for chiming in. Some questions;

Did the GIAC tune factor in the exhaust work, or was it flashed prior to the mods?
What were the dyno numbers before and after?
Is there any drone from running the setup mentioned above?

John D II

Hi, The flash was done after the exhaust work. The car was not dynoed at that time. The owner of the car subsequently flashed it a few weeks later. I am not sure if it's been dynoed since we had it or not.....During our testing and development, I had occasion to drive the car repeatedly with the SpeedTech exhaust and I could not detect any drone whatsoever.

Needsdecaf

It does. It just depends on how mod friendly your dealer is.

Highyo

there are a significant amount of people here that believe tuning a 911 is something akin to tweaking the coloring of a picasso. or that its a slippery slope before this forum is full of "modders" who just came from their mitzy turbo or e9x m3s.

for shame

subshooter

I am one of them but I am not married to the idea either. I have much more trust in Porsche's engineering guys than any aftermarket company that is tuning our cars and offering no warranty like Porsche does.

Also, if the tune really does increase mpg as others have said, why wouldn't Porsche do this up front since they are under so much CAFE pressure?

LavaGTS

You have to think beyond that. Porsche as a company knows what they are doing.

Let's just take an educated guess that the 991.2 power plant is going to be used in the next generation 911. The next gen HAS to have more HP/torque. Why maximize the potential of the motor on yester-years model? They're going to up the boost and/or do some induction work for more HP on the new car using the .2 components power plant. Porsche cares about Porsche.

As for MPG.. I'm pretty sure that's only achievable through granny driving and not exceeding 2-3k rpms. The MPG inscrease would make sense if you had add a more free flowing exhaust.

surquhar

Tuned cars get better MPG because the tune leans the car out. Cars come tuned from the factory on the rich side.

Highyo

the battle of engineer vs marketing guy usually ends with the latter winning. maybe that's why each year shows incremental gains in HP, torque, fuel efficiency, etc.

Needsdecaf

Yup.

Valvefloat991

This is only true at full, or near full throttle. At part throttle all modern cars with gasoline engines operate at stoichiometric air-fuel ratio around 14.7 to 1, because that's where the catalysts effectivley reduce the three controlled pollutants. Stock cars tend to run rich at full throttle in order to provide extra cooling to preserve catalysts and turbochargers.

I suspect that modified cars operating at higher-than-stock boost pressures, need this additional cooling even more than the stock engines do.