Gibbo

Hi there


My car has fabspeed airbox modification along with a BMC panel filter, so a little improvement on the intake breathing.

My car has PSE which is set to always on by disconnecting in the engine bay.


I keep looking at the stock 997.1 C2S headers and they look so restrictive and the X51 headers look far better flowing.


Now I've searched and searched but no one seems to comment on if there is any performance improvement from the X51 headers or not. So those of you who have had X51 headers installed, what are your thoughts, any sound change, noticable performance gains etc? Has anyone ever dyno'd with X51 headers?
Or any numbers from track where the X51's have given you better track results?

Gibbo

Come on there must be loads of you with X51 headers who can comment please, anyone?

Edgy01

I put the X51 headers on my 06 997S cab in 2007. I found that the biggest issue with them was a different sound. I am suspecting that there should be some reduced torque (very little) because the tube size appears larger.

Gibbo

Do you preferre the sound with them?

larrytrk

Put X51 headers on my 06 S with PSE, better sound, no appreciable power increase.

Skibum

If it is improved horsepower and less restriction and better sound that you are looking for, forget the headers and get a set of sport cats. They will do far more for you than replacing the exhaust manifold.

Edgy01

Yes. Get many favorable comments--even from the Carrera GT guys!

Gibbo

Would you say the X51 headers cause the exhaust to burble and pop more when you come off the gas?

808c2s

In my experience, when I replaced the stock manifold for the X-51 version with stock muffler, no appreciable power increase, and no burbling of the exhaust sound. Upon putting on the TUBI mufflers, oh, such a beautiful burbling sound between shifts and upon deceleration!

Seal

I've got a 06 C2S with PSE and X51 headers and it burbles nicely and sometimes pops. It sounds great. With PSE open all the time and X51 headers torque seems to be more linear FWIW. No dino so it is just seat of the pants feeling. May have something to do with the flaps in the PSE being open al the time vs opening and closing.

I read a story that PSE adds some power but that Porsche doesn't state that because otherwise they would have to get re-certification of emissions etc from DOT. Not sure if it is true or urban myth but it is a nice story.

I didn't regret putting X51 headers on, that's for sure. That and GT3 lower contol arms to get more negative camber are my favorite mods and have made the car much more lively.

Seal