SM_ATL

This is right. I missed your comment about most of the driving done on busy street and low rpm torque. By the time you have invested in higher rpm mods that will not help you, you will have spent as much as the depreciation hit on your nearly new 991. Trade it in and move on to something that has a really stronger low rpm torque curve.

carrerapete

I had a severe lag when driving in city traffic with my 392 Hemi-Challenger; I felt like sending it over a cliff only days after bringing it home.

I started looking for a solution to the problem and discovered this product:
http://www.sprintboosterusa.com/

At first I believed it was "snake oil" but it comes with a thirty-day money back guarantee, so I figured "what the heck."

The long of the short: the product exceeded my expectations. The lag was gone and the car had great linearity in the pedal (it no longer felt like "drive by wire"). Of course there was no actual power gain, but the remapping made the car very responsive when pulling away from a traffic light.

I also installed one in my Jeep Wrangler, and it also greatly improved that vehicle's response and helps greatly with daily driving around town.

I'm not sure if they have one yet for the 991, but I'd check and give one a try: you can always get your money back if you're not happy with the product.

HotLap

I too can vouch for the effectiveness of the Sprint Booster. I installed one on my 2008 BMW 535i and it made all the difference in the world by eleminating the built in throttle delay. Was the best $250.00 I spent on performance mods in a long time. Did not add hp - simply remapped the accelerator curve and felt like "this is the way the car should have come from the factory". I had one on my 2009 997 C2S as well and it did make a difference there too. This is a simple plug 'n play that you can easily disconnect before taking the car in for service, etc.

BGB Motorsports

Unfortunately, if you can't bolt a larger displacement motor to it, manfiolds/headers are the only way to increase torque. Headers tend to be very expensive which is why it's a nice option to have something affordable for the street. Fabspeed seems to always be ahead of the curve with making some new for the "new" car. If you have the budget and the neighbors or your passengers don't care, the only thing that will bolt-on and produce double digit lb/ft is a manifold. Obviously if you found a way to add 50% more air with bigger intakes and throttle bodies you will get close to the gains of a manifold but if it's not forced induction, you can't unfortunately tune in more torque. The latest files for the 991s seems to have all of our "racing tricks" for using the ECU to add torque levels but I would be hesitant to say that adding simply our flash would increase torque without all of the other bolt-ons we have in the form of pulleys, intakes, headers, etc.

I'm speaking only in terms of 3.4L and 3.8L 9A1/DFI engines that we have dyno tested through our development with them since 2009. I can't speak to the bolt-on abilities of the port-flow motors that were used from 2005 though 2008. When we dyno'd the first 987.2 Cayman and it made 299rwhp on race gas, we added Fabspeed headers and saw nearly 15hp and nearly 10 lb/ft. We flashed it and saw another 13hp and 9 lb/ft. People that design headers for a living are good at using them to make power. Rarely do you get stuff that loses power unless you didn't do your homework. Then it's a question of what fits best and what works for your program i.e. long-tube headers for torque or shorter-tube headers for horsepower. Given that it's a street car or a DE car, i would choose your header based on how much torque it adds, not horsepower. Your butt dyno can feel torque but it's too hard for it to feel hp.

mdrums

Header are part of the exhaust system....headers/cats/mufflers/tips///= complete exhaust system.

Just installing headers I highly doubt that will give you 17hp increase. When companies quote a increase of HP/TQ you really need to see the dyno chart of stock vs mod's on a same same day dyno test to see the total picture of increase...was there a decrease of low end torque?....where is the increase on HP in the rpm band?...this all matters.

Detroit Shooter

I also don't believe Porsche would leave that much easy HP on the table. Does not make sense.
The stock exhaust is no slouch, those are not cast exhaust manifolds.

Team Plutonium

I just installed the Fabspeed Sport Headers, and they are indeed beautifully made.

I'm also running the FVD Brombacher x-pipe, and the Sharkwerks side free flow exhaust, so my car is on the louder side.

So far I love how responsive the throttle is, and the total combined additional power gain is noticeable. In the end, I mostly did to save some weight and add sound.

I am getting a CEL however with the 200 cell high flow cats, which I really shouldn't. I'm gonna cycle it a couple more times to see if it goes away, but I might have to pick up the Fabspeed 02 sensor spacers... that should do the trick.

exponential

Long tube headers will give power band at medium RPM. Shorter tube headers will move power band to higher RPM.

Long tube headers will match fast road cars. Fab Speed header got shorter tube and I do not see any reason for that as with the standard cam, we shall not get more HP at higher RPM so why make the header shorter??

Non modify 991 engine need long tube header

Team Plutonium

Well, the Fabspeed headers come with 200 cell high flow cats - so that alone will give you a small power bump.

kosmo

I wish for bigger intake openings

Chris@Fabspeed

This is very basic information that is incorrect. If we are talking about old engines, with fixed cam timing, non variable plenums, ect. then yes usually the shorter primary lengths will give greater gains on the top end.

With these new high compression/direct injection cars and all of the technology designed to give nice, broad, flat torque curves, exhaust backpressure has more of an effect on the powerband.

Here is an updated dyno chart for our 991 Sport Headers - the one on the website is incorrect.

Chris@Fabspeed

This shouldn't be happening - we are using HJS HD Directional cats on the 991 (Euro Level 5 emissions compliant). What are the codes it is throwing, and how soon after bolting on headers did the CEL appear?

Team Plutonium

Hi Chris,

The CEL showed up after about 3-4 cycles, approximately 10 days after the install (I was traveling and didn't drive it much after the install).
I drove yesterday and after the warm-up phase I got the CEL. Attached is a screen shot of the codes we pulled yesterday. Thanks!

Chris@Fabspeed

also for anyone reading this thread that WANTS headers, but can't justify the cost, we have a set of dyno time only developement headers that produced the gains in the above dyno chart. We are selling them for a discounted price of $1600 as they are not new. They still come with our industry best 2 year warranty on the HJS sport cats.

Nicoli35

Oh, now, you didn't need to tell me that. I enjoy the Fabspeed maxflo mufflers every single day combined with PSE, just pure music in quiet and crackling thunder in loud mode.

Wife just bought me a nice watch for our second anniversary and I really can't say well honey, here is the watch back, please get me these headers instead, lol.

Sigh. Two weeks earlier and might have had a chance.

Hope someone grabs 'em and enjoys 'em.