Let's talk Cats (Catalytic, not feline)

[epdarks]

I would go to a junkyard, hack out a stock X5 cat, weld it into your exhaust system, PROFIT.

[Green Dragon]

I have catless headers on the way from calico coatings. Its their a high-performance Black Series ceramic coating , good to about 2000 degrees.I am going to add some high performance catalytic converters downline at some point. Those high performance headers with the built-in catalytic converters look pretty sweet.if you compare those to the stock headers they definitely look like they will flow better. They should fit just fine with the exception of a modification to the mid pipe. It needs to be lengthened an inch or two. As far as a cel light, there are a few ways around it if you do run catless. I have a shark injector already, but I dont think it has the test pipe tune.... It can be added it think. Active autoworkers might be the best option. I'll have my headers on in about two weeks.

[Ricky Bobby]

Originally Posted by X5SND

T, I was a couple steps ahead, but on the same page as you with regards to their inconsistencies....it's part of the "additional info" I'm currently waiting on!

Ricky, I don't have a pic offhand, but will try to grab one later off google....the flanges and post-collector bends all look like they'd be good to go, but It's hard to know for sure without some specifics length wise.

What is this "shark injector" and Is it along the lines as the ESS stage 1 software? ---I have to look into it yet. If I absolutely need it, no biggie, but would like to stick with the ESS stuff if possible.

Found here, its probably similar to the ESS tune although I'm not sure what their tune entails, member "Green Dragon" on here has the shark injector tune with his facelifted 6-speed M54, and he loves it.

ESS tune looks to be about 700 bucks, and to be honest unless you needed it for something custom (as in deleting a CEL file with a high flow cat) I'd just get the shark injector. NA tunes aren't that different because theres only so much fuel injection and timing you can tune out of an NA motor without boost. You may get 5 hp overall, but its the response of the throttle and the torque curve that might change.

BMW Shark Injector (Conforti): Bimmerzone.com

[4.8isX5]

My buddy pnoyx5 on here you guys know his s/n, but he has the magnaflow hi flows on his, 4.8is though.

[J.Belknap]

HJS 200 Cell cats.

[X5SND]

@darks: The only problem with the junkyard parts is that I don't really know what I'd be getting. I'd also like to get something a bit more free flowing for a few more mods that are in the books.

@green dragon: keep me posted on the status of your headers when you get the cats in. A buddy has a built 94 supra with the exhaust manifold done in a plasma Sprayed ceramic coating...looks sick! With regards to the headers w/ integrated cats I posted earlier, IMO it seems like a shame to buy something that's built so beautifully only to have to then hack it up to make it fit. I know it's only maybe an inch or so....but if I'm going to dump down that kind of dough, I'd be nice to have it fit properly from the get-go! Lol.

@RB: Interesting...I'll have to read further into it....but I'm wondering how it would effect things further down when it comes time for the ess software....I don't think I "need" any software flashes just yet, and would prefer not to have to buy things twice. I'd eventually be flashing out the shark tune with the ess stuff anyway.

@4.8is: I read something about that earlier, I'll be shooting him a pm to see which ones he used (magnaflow makes a few different models.)

@J.Belknap: thanks for posting that...it'd be interesting to see how those stack up against some of the other aftermarket obd-II compliant cats that are available (for around 1/5th the price)....some are even Cali-emission legal! For my application though, as long as it keeps the CEL off, and breathes easier I'll be happy!

I'm still waiting on a response for the details of the system I posted previously, but seeing as its the second day without a response I have my doubts that the company has any idea of the differences between chassis of the e53, and e46 length-wise. Hopefully I'll be putting my foot in my mouth on that statement but we'll see!

[J.Belknap]

No worries man.

[Ricky Bobby]

Belknap has a point, the HJS cats are probably some of the highest quality ones on the market and are known to be efficient enough to not trip a CEL on some PZEV (CA emissions) cars, depending on your setup. AWE Tuning in the VW scene uses HJS cats and although the exhausts are pricey, they guarantee no CEL even with a full turbo-back exhaust.