High Flow Headers - 200 cell cats in a GTS: Yes or No?
 

Gens,
Could you please help me to decide about a High Flow Headers with 200 cell cats for my GTS: Wondering if it's truly an improvement in a GTS.
Cheers,
T.

I'm on the fence about it myself. I've spoken with the gents at BGB down in florida. They do some racing with these cars/engines.. I was advised that the cargraphic would be good bet. Of course they also sell those so it may well be a bit more than a happy coincidence.

I like the sound with the sharkwerks bypass I've got, but there could be more pop/bang/gurgle.. I'm thinking the 100 or 200 cell cats and long tube headers will do it. I'm not so sure it'll make power, but if/when I do it.. it'll be for the sound.

"The 200 Cell Sport Catalytic converters actually flow better then the 100 Cell version, that's why most manufactures are using them now. The reason is, a 100 Cell Cat has about 2-3 pins that must go through the entire cat at different angles to keep the Cat core from collapsing on its self and coming loose. A 100 cell Cat is not as strong due to less cells, so the pins keep it from moving, but it causes a flow restriction, due to their size. The 200 Cell version flows better and is more durable. It also helps keep the CE Light off better and is more compliant with emissions and inspection"
Source: https://rennlist.com/forums/996-foru...orth-it-2.html

Reviving an old thread to get some more traction... Any GtS owners with aftermarket cats ?

Hard to do. The cats referenced above are for 997.1 which easily replaceable cats. Cats on 997.2 GTS are a part of the header. So you have to replace the header in order to replace the cats and then you realize you're replacing an X51 header which is $$$ for 7 more HP.

Food for thought.

Attachment 1104507

Aren't the headers on a 997.2 C2S and GTS the same? The powerkit was all on the intake side I thought. Correct me if I'm wrong...

I'd always read they were different but I've been wrong before.

EDIT: Checked PET and didn't see a different header part number for IX51 (powerkit) so they may be the same. I probably confused the inclusion of PSE with the X51 as also including X51 bespoke headers/cats.

Either way, just know you're replacing headers and cats at the same time and not just cats so it's going to be pricier:
i.e. http://www.fabspeed.com/porsche-997-...sport-headers/

Or,

:http://topspeedauto.com/porsche-997-...ic-converters/

Here's another option which moves the cats down stream a bit to where the 3rd muffler would've been: http://www.fvd.de/us/en/Porsche-0/-/...atalytics.html

I think you'll always get more flow with freer flowing cats but you'll need an ECU tune to get the most out of it (and possibly to disable the CEL you may get). As for longevity, I've heard HJS cats are quite good and can stand up to track use (which Fabsteed and FVD both use).

For the gains all 3 of these are claiming I am assuming that is for the non x51 headers correct. The x51 already has a nice bump over standard headers.

I guess the question really is, what are the gains from x51 to these.

We're talking about 997.2's. I believe only the 997.1 powerkit came with different headers while the 997.2 powerkit is all intake changes and no exhaust changes.

yes that's the real question

Does that mean the 997.2s have the same or similar headers as the .1 x51? If that's not part of the power kit anymore, assuming it means all .2 headers are more efficient

Sorry. Still learning...

The 997.2 engine is quite different so no, the headers aren't the same as the 997.1 engine (either X51 or not). I don't believe there's many parts that carry over from the 997.1 engine to the 997.2's.

fair.. and agree.


I guess I am lost then. Does the OP have a .1 or .2 car? The few options posted above look to be for .2 cars given the cat integration with the headers.


If so, then what I am hearing is those gains are true because .2 does not offer different headers even on the power pack or x51.