Exhaust question
 

How much of the 997 gt3 exhaust bolts up to our cars? What parts would i need?

Is it possible to swap the header and muffler and run a pair of crossover pipes to the exits on the bumper cover?

Karl

I believe you have to run the centre exit bumper with the 997 exhaust.

Pretty sure that if it is the 3.6 you only have cosmetic issues./ I am running the 997 cup parts on my 996.

Ray

I understand that if I run the whole of the 997 exhaust I need to swap out the bumper for the Cup bumper. My scheme at the moment is to run the 997 header, and the 997 muffler only and have a custom runner run from the passenger side muffler to the drivers side cut out on the 996 gt3 bumper , and likewise from the passenger side to the drivers side.

I am curious to know what parts I need to this, i.e., do I need the 997 brackets and exhaust hangers? Do any parts need to be fabricated to run the 997 header/cat and muffler, or does it all just bolt right up?

At this point I am just in the planning phase and looking to determine the plausibility of the idea.

This seems like a lot of work for a street muffler. That said, my own experience are in the non-street systems.

Ray

You're saying you want to run the 997 headers and 997 SIDE mufflers???...wth no center muffler and just fab up pipes to exit at the stock locations on the 996 bumper?

IDK what you expect to gain from this the side mufflers are the first thing to go in all of these systems and the major restriction and huge heat sink. 997 GT3 exhaust on a 996 GT3 is one of the few exhausts that works and makes some power on these cars, but everyone that runs it runs the headers and side muffler bypass pipes with the center muffler only.

The setup I believe you're proposing won't even sound like a 997 which is the other draw to going to the 997 system.

Thanks for tuning me on how others use the 997gt3 exhaust. I searched and search and found nothing.

I was planning on the side muffs and exiting on the stock 996gt3 exits. My thoughts were based on the Sharkwerks center muffler delete.

I get the heat sink issue though.

Is there enough room for the center muffler with the cup bumper? Does it bolt up, or do I have to fabricate anything?

I had 2011 RS exhaust on my 2004 GT3 which, along with CF cup bumper, saved over 70 lbs off the back of my GT3. The 997 headers and cats are compact, single-piece units with equal length tubing which is much improved. You'll want new header gaskets and header bolts when making this swap, obviously. The O2 sensors need to be customized to reach your engine harness because the 996 exhaust crosses over and clips into the opposite side for rear sensors while the 997 system doesn't. If using the 996 Cup rear bumper then you'll need to get creative with the aluminum rear bumper beam and remove the rivets from the bumperettes to clear [which is what I did] or remove the bumper beam completely which I think is a bad idea. You'll also want the Cup car heat shielding for this bumper.

For mufflers, the above posts are correct. I had Ti center muffler only with FVD single tube bypass pipes which comes with secondary inlet blockoff plates. If you go with the 997 RS muffler then you also need the muffler straps and a correct 997 muffler bracket because the 996 bracket won't work. Goes without saying that the cat pipe to side muffler clamps and center muffler side flanges are also needed.

I was going to test an idea which allows keeping the stock 996 GT3 rear bumper and side exits but leverages the 997 GT3 headers + cats. If you're interested then email me through Rennlist.

All of this begs the question: how much is the 997 cup bumper?

996 Cup bumper is approx $3-$3,500 from Porsche Motorsport. It is made out of Kevlar and very nice.

Thanks, and of course it would have to be the 996 bumper. $3k + is a lot of track days...

https://cimg1.ibsrv.net/gimg/rennlis...f71fbe3d26.jpg
It's worth it IMHO. :)

Dammit. Wish you hadn't posted that pic. You wouldn't have another shot from behind, by chance?

https://cimg0.ibsrv.net/gimg/rennlis...f484182346.jpg


Ray

I have the 997 headers and cats. From the cats they criss cross to the opposite sides like you are describing, but I don't have the mufflers. It is very loud.