realien

Hey guys,

I picked up a pair of the shorty headers from eurocharged, and deciding what else I'll do with the exhaust, I'm looking for some nice grunt when under throttle but want it calm while cruising at highway speeds. I'd like to keep at least two cats so I don't get crap when doing emissions.

Questions

1) Can I fit some after market 3" cats where the original 1st cats were ? and then just do an X pipe and delete the 2nd cats and resonator ? ( if I go this route does anyone have pipe diameter, cat and mandrel bend recommendations ? ( was going to buy some bends that can be chopped and welded to fit), and would you recommend a flex section ?
2) Has anyone got shortie headers, x pipe and cats and if so what order did you do flow wise ?

looking at this pic from someone else's car with stock headers, the x pipe and deleted resonator is what I'd like, but not sure I can fit 3" cats where his stock cats are..

Ls1toAMG

I would try 2cats and res delete and put an x pipe in place first. It's the most popular. Most of your sound change will happen when you change mufflers or gut the soundproofing out of them

realien

Thanks, any clue on which cats will fit there ( since I'm ditching the stockers)

I was looking at

Flowmaster :

http://www.jegs.com/i/Flowmaster/389...ductId=2159313

Magnaflow :

http://www.jegs.com/i/Magnaflow/642/...ductId=3150982

These look to cheap to be true :

http://www.ebay.com/itm/3-Thunderbolt-Catalytic-Converter-High-Flow-Stainless-Steel-/140941752250?vxp=mtr&hash=item20d0c877ba

realien

did some searches and bought the thunderbolt cats, some 3" SS pipe, 3" SS bends and a 3" SS X pipe from performance curve

http://performance-curve.com/

incase anyone else is searching for the same parts :

SICAMG

They should fit real nice . Remember its only welding and cutting.....you can build around anything as long as you have a mig or tig welder!!

Hulk

I had thunderbolt cats, they work good. Never got a cat code with it so you should pass emissions

realien

Thanks, do we just have 2 o2 sensors , left and right before the cats or does the damn Germans have 4 ? 😄

Hulk

Pre cat 2 and post cat 2

4 in all

AgSilver

The secondary O2's can be turned off with STAR.

realien

I have the Eurocharged ECU updates, so am assuming they'll turn it off when they send me a new file for the headers.

2000UZJ

IIRC the tune itself cannot turn the rear O2's off. It has to be done via STAR. I am still battling a CEL due to no cats. Which is the main reason I am installing cats...mmeeooww...

SICAMG

Hulk...power wise is it worth cutting off the factory cats and installing the 300cell version from thunder?

AKnight55

EC headers to x pipe and e63 mufflers. The sound is insane. The smell is a bit much, but no drone and quiet while cruising

Hulk

I had 200 cell cats , wasn't a big gain. I don't don't know if 300 cell is more constricted.

realien

I'll have new cats and bought some bungs to weld in after the cats, so hopefully I won't need to turn the sensors off, I got the "spacers" too that help the 02 sensors get a restricted flow

JoeNobody

You can install small'ish cats before the x pipe. For inspiration checkout American Racing Headers E55 long tubes, and see how they fit the cats in.

2000UZJ

Here are the American Racing Headers with no cats on my car. The smell isn't bad if you are strolling through town. It reeks on the race track though. Those behind me say it's not a pleasant experience to the nostrils, although the exhaust note is to the ears.

DVC

Damn, those ARH don't age pretty.

realien

Do you have to smog and worry about 02's or not an issue where you live ?

realien

I got some 02's bungs and the right angle adaptors if I need the ECU to see less flow after the 3" cats, should get it in next week or so and see results..

I was bidding on some E63 mufflers and someone sniper'd me by $10 at the end, bummer, he got them for $710, quite a deal.

2000UZJ

In there defense the first car they were on burned to the ground...they aren't pretty but they work!

I live in Sandy Springs. I will need to do something before I am due for emissions. I don't plan on keeping the car de-catted for much longer. It's a pretty raw exhaust sound and I'd like to tone it down a notch or six

realien

I got my car back on the road today with the Euro Charged shorty headers, 3" piping, X pipe and deleted resonator, all I can say is holy crap, I better save money for the upcoming tickets. I can't believe how fast it is and how well it drives, this is going to be a lot of fun.

only remaining issue is to find some 02 harness extensions for rear 02 sensors, they are apparently made of unobtainium so I have a CEL right now for an open circuit since they aren't connected.

JoeNobody

You can disable the rear sensors, but it's better to actually hook up the rear sensors so you can monitor the race cats (and be easily smog checked)

realien

yeah, I'm looking for extension harnesses, people claim they exist, along with Unicorns... I'm trying to avoid having to cut, extend and use connectors..

AMG__POWER

I have the EC MID lengthand love them and the sound