I've been told to leave the headers stock (intake too) up to 600 or 650 HP.

AFAIK, the headers are the same across the turbo variants.

Jeff

 

I asked Todd Knighton the question when I was doing my stuff and his answer was like many above i.e. "don't waste your money."

 

I'm wondering though, when everyone says 600+hp, are they talking AWHP?

 

Those look Chinese... inferior materials, welding, etc.... all grinded down and coated to look good.

These are what headers look like that are made of thick walled(insulated) steel. These are the first set of Boost Logic headers that I have been helping with the R and D on over the last 6 months or so, and therefore, not a production unit(test only). This is the look you want to see in a non-factory header and keep in mind that this is not even a production set.

That thin walled chinese crap is prone to cracking, breaking, leaking, etc. Keep it stock if you are thinking about those Schnell headers.

Justin

 

This is one of the things I've been trying to find out exactly about the X50. The information is no longer available through the Porsche site of course since it isn't a current model, but I found an old Porsche brochure and it mentions that the X50 includes a "revised exhaust system" versus the stock Turbo. I have been unable to find any concrete information about exactly what they mean, but through discussions with some Porsche people I was led to believe it used different headers.

 

The PET number (part number) is the same for the 996tt (both),
and GT2. I also know of no difference in the cats or exhaust...
Odd about that brochure... I'm not an expert in the X50 option,
but I believe all it is, is the k24 and the programming required
for it, though they may get the steel syncros in the tranny too.

 

Joe, you are correct, 996GT2, TT, X50TT all share the same headers. Same engine components, same intake plenum. I guess the factory headers are pretty darn good.

are there any verified dyno graphs on stock k16 and k24 cars to show an improvement in power?

 

That is a great price ! Fabspeed sells these for $ 1250
You can recognize the Asian headers by their 1 piece CAST collector.
With a little luck they won't crack at all.

 

Never had 1 header crack to date.

I did my own testing and gained HP on 2 different 997TT. Never did a 996TT test. But headers are the same for those cars. Dont know if it is VTG related but look here -

 

Interesting. So that's a little loss from idle up to 3400rpm,
then a little gain up to about 4400, then a significant gain up
to about 6000, then back to about the same...
And is that with no other change at all? I'd be interested
in any new data for 996tts, and yes the VVT might be making
a difference because of the increased upper flow. What diameter
headers were these?

 

Glad to have my AP headers on

 

That curve makes sense. you loose power at lower flow, then you gain power the higher up you go. Seems like at a certain point the header curve really keeps the power and torque level, where the factory headers drop off. I presume these were stock cars. I'd bet ported headers would give similar results.

I can say that my beautiful custom(not chinese made) headers removed about 50% of the drone I had before. Car is louder, but has less drone, so that is one positive aside from possible power gain.

 

here are mine port matched and polished. On a 140k car I think quality custom headers are the only upgrade. Otherwise porting is a good option to cheap headers.