ak432

I'm sure there are many threads on the subject of exhaust modifications and associated issues with warranty. Like you, I usually play it safe, but my understanding after reviewing the law and via personal experience with ferrari and Porsche is that exhaust modifications (including headers) WILL NOT VOID THE WARRANTY of the engine or drivetrain. I'm sure others will chime in with their opinions on this.

The stock GT3 exhaust sound was honesty terrible to me. It was significantly worse than my 991 S for example. Just a side muffler bypass improved it drastically and improved my enjoyment of the car significantly. As far as power though, I agree……I definitely wouldn't waste big$$ for small barely perceptible gains.

Mr. Adair

I think I know where he is coming from…

It's in our nature to seek a few hp's if it can be done with no risk. Hell, on the Planet 9 Cayman forum there are pages of threads on tuning. Including pages and pages dedicated to ECU tunes etc. I got an additional 25hp (dyno confirmed) out of my Cayman S Sport with a plenum/throttle body (from the GT3 of course) and ECU tune. The BMW E46 and E92 communities are getting great results as well. So I think that is more of his question. Not that GT3 is woefully underpowered

It is curious to note though that to date all we have seen is exhaust modifications to this car. To my knowledge in many cases even from the factory ECU mods are very common from gen to gen when looking for performance gains.

Are we still too early in the aftermarket development stage (just 24 months on these cars) on an ECU tune or is it just that "right" from the Porsche factory? I say that because every car I have had ECU tunes on have run better.

GMG Jamie?

hfm

I think it's safe to say there is a spectrum of cars from Porsche, some detuned from the factory that can be tuned to work better. That likely includes Boxsers and Caymans save the GT4 (except maybe for gearing).

The GT3 on the other hand was taken to its limits already. I'd be very surprised if an Injen intake or Crawford Plenum or something of that ilk that you see in Japanese cars, as an example, that would really do anything for the GT3. Maybe someone is willing to void their warranty on a $150K car to find out.

Jamie_GT3

We'll have baseline dyno for our 991 GT3 headers tomorrow. and Dyno on the headers/exhaust on Wednesday. All of the bypasses and what not, don't add appreciable power and are predominantly done for sound and weight.
We get power, sound and weight reductions with our system...

hfm

Modding for power by experts.

awew911

I've learned that when I stopped chasing additional horsepower and instead, focus on quality driver edu cation with groups like Chin, I can ga in much more performance out of myself.

If you plan to track the car, unless you are in a race and you have the skills to take the car to its limits, you won't be able to take advantage of (nor feel) 20hp.

The engineers at porsche optimize performance and durability. Any major changes and you are on your own.

Like many here, add a center bypass and enjoy.

Tapeworm

Companies like Porsche spend huge amounts of engineering resources makeing sure they can get the best compromise exhaust system that trades off peak power vs low end torque, weight and avoiding drone. The thought that another company with two or three prototypes (if that) can significantly improve *all* these areas is naïve.

In almost all the systems I have seen (and tried on other cars), all you do with a more free flowing exhaust the is move the torque curve UP. Yes, you will get some top end gains, but you will loose torque low down where you spend most of your time driving and enjoying the car. It's hard to measure the torque low down, Dino plots often start at 3,000 rpm or above. I would be interested in someone showing in-gear numbers from 1,000 to 3,000rpm after any exhaust modifications to see the real effect on this low rpm rev range.

Drone, resonance, they will be worse, and these can really effect the enjoyment of a car.

The best mod for a car is driver education and more fun driving experiences, get the most out of the car you bought and in a few years, buy the next or a different model. My $0.02.

fxz

better made Intake filters and exhaust systems
will give you 25HP
but to do what?

karimgt3

Good point.

But then again, when are you really using the 1000-3000rpm range on track? Almost never I suppose.

Also, it is true that porsche spend a lot of time and money on what u stated above, but don't forget that it is done with strict restrictions on CO2 and CO etc, before getting into drone and noise.. thus they can't fully exploit power and torque in their systems as you would imagine.

MileHigh911

Please record an honest dyno for the RL crowd. This will be the first "PIWIS enabled" dyno that I know of. Most trying to sell a product will create a scenario for obvious change to make their product look good. Often they purposely leave the "exhaust sport" button turned off, then when they add their system it shows gains. But these gains are not always true. If an owner was to keep his exhaust OEM, then of course he would have that button pushed on 100% of the time. So record dyno runs with the button ON and OFF for the baseline please.

Mr. Adair

Agreed. Only referring to ECU..

Mussl Kar

Less power for your first track car?

Mr. Adair

This^

Seriously, nobody including myself doesn't think there is not TONS of improvement to get out of OURSELVES in regard to performance. I get it!

That said, I think it's funny everybody thinks GT3's are tuned to an inch of it's life. No way. In general (and I'm no expert, although I am talking like one all of this exhaust/breathing mods that happen from headers back can even be better if ECU's are tuned to match. There was 7hp from the Porsche factory from the Cayman S to the Cayman S Sport in the ECU.

In any case, I'm really just curious. Not looking to do anything. Curious as to why none has delved into it yet. If there is nothing to get so be it...

zedcat

First track car?- also suggest browse the threads here like Orthojoe's track journal and look into tires, brakes, safety gear. You'd likely want to consider those areas before anything power related.

Serge944

I think you are absolutely correct if the aftermarket companies had to play by the same rules. I wholeheartedly agree that the aftermarket would be hard-pressed to produce an exhaust system that improves performance while meeting the same emissions and noise standards.

Once you take noise, NOx, CO, and HC emissions out of the picture, your argument isn't as strong.

Nevertheless, I agree that the stock Porsche exhaust is more than anyone will ever need. But, there is something to be said for modifying cars, and that's a hobby in it's own right. When I built my 4 liter, it wasn't for the end result of more power, but for the journey and learning process it took me on. That alone was more fun than actually driving the car!