Schnell Headers on 986 with Stock Exhaust - 986 Forum - The Community for Porsche Boxster & Cayman Owners

panameras · 08-05-2007, 12:01 PM

Hi fellow Boxster owners

Im about to purchase a set of Schnell exhaust manifold for my 2000 Boxster S, mainly for the purpose of sound but Im wondering if it would give actual performance gains with the stock exhaust system in place?

Two reasons that I have chosen Schnell, 1: cheapest I can find (please link me if you know a better/cheaper product. 2: being a 2000 boxster s it doesnt have any cats near the manifold, fabspeed offers a set of headers with cats for double the price which i dont think i needed them.

Please share your thoughts.

jwilson95 · 08-05-2007, 12:28 PM

I would think you would get a performance gain and sound gain from any brand out there from what I have read. The Porsche OEM headers on 2000 up cars have 4 cats. 2 integrated in the headers and 2 further back.

I have seen the fabspeed online and looks like a great system, but expensive as you mention. I also have interest in the maxspeed motorsports headers on ebay which are the only ones I have seen in that price range with 4 O2 bungs in them for the oxygen sensors.

From what I have read and talked with my local Pcar indie shop, you can expect 10-15 HP gain from headers depending...

Anything is better than the horribly designed system from Porsche. Another "keep the Boxster below the 911 in performance" design.

Let us know what you go with and how you feel about the change. I feel that is the next mod I will be doing to my car.

panameras · 08-06-2007, 02:36 AM

Thats weird I could only see two cats in my system, unless (see pic) that tiny pipe with a oxygen plug on top is the one of the second set of cats. There definitely no cats intergrated with the headers. If not I guess an possible explaination would be although my is classified as 2000 model but it actually was built in 99 (as what it says on the built plate).

Any more info on the maxspeed motorsports headers you mentioned?

edevlin · 08-06-2007, 09:06 AM

I only picked up 6hp at the wheels on my 2.7L 2000 Boxster based on a before and after dyno runs when I added headers and a single pair of 100-cell cats (replacing the two stock pairs). A small hp gain, especially for the cost, but, boy does it sound sweet....

Ed

Adam · 08-06-2007, 12:50 PM

Panameras, the stock system on 200-2004 boxsters looks like the one on the left.
It looks like the manifolds are missing in the pic you provided!! Maybe it's just the angle....take a pic of the underside of the engine!!

jwilson95 · 08-06-2007, 01:28 PM

A pic is attached of the stock headers with horrible merge collector and integrated cat converter.

You can see the 4 O2 bungs (2 precat, 2 postcat) I have referenced. The problem is extending the wires of the 2 precat O2 sensors so that they are now 4 postcat O2 sensors in order to not have CEL's when you install new headers that remove this terrible OEM design. I want to check with my local Pcar Dealer to ask his thoughts. I want to keep all O2 sensors if possible.

Maybe some other guys have done this successfully already?

panameras · 08-07-2007, 09:05 AM

Quote:

Originally Posted by Adam

Panameras, the stock system on 200-2004 boxsters looks like the one on the left.
It looks like the manifolds are missing in the pic you provided!! Maybe it's just the angle....take a pic of the underside of the engine!!

Adam, is that the Fabspeed muffler? how does it sound any drone?

noone986s · 08-08-2007, 12:13 AM

For reference attached is the picture of the OEM header I removed.

Thanks

Adam · 08-08-2007, 04:22 AM

Quote:

Originally Posted by noone986s

For reference attached is the picture of the OEM header I removed.

Thanks

That's the same exhaust manifold the 2.5L cars have. It looks like you were correct in assuming the non-US 2000-2004 cars are different.

noone986s · 08-10-2007, 01:12 AM

You could install these electric ones.....

http://www.badlanzhpe.com/index.html

.....and then get a cheap shift light circuit from ebay, hack it and use the ouput of that to drive a relay circuit (rather than lighting the shift light) and you could have a configurable exhaust valve.

If you could have the valves opening into bypass pipes then I think you could be on to a winner. I am not 100% on the sound but like the idea.

Cloudsurfer · 08-11-2007, 06:39 AM

That could be one way of doing this, though I am thinking of a more progressive opening, over say, a 1000 RPM from beginning to open to fully open, rather than just a hard RPM point from open/close.

There needs to be a bit more engineering put into this, perhaps it will become a winter project.

Patrick

panameras · 08-14-2007, 04:24 AM

Just put my order through for a set of Maxspeed headers. Will dyno it afterwards to see how they perform on my 3.2.

Baseline was 168rwkw on a very hot day.

rule1 · 08-15-2007, 03:34 PM

good choice!!!

jwilson95 · 08-15-2007, 06:34 PM

Hey Panameras-

Please update us on the results from a HP gain and sound/feel perspective. I talked to my local pcar mechanic and his basic answer to me was, "WHY?". You're not going to gain much HP and going to be throwing CEL codes all over the place. Our situations are different because of the integrated cat in my headers. I think I'd be much more likely to do it if we had the Euro headers here with only 2 cats.

Good luck and hope you like them.