HIGH FLOW Catalytic Converter for B7 S4

[neo]

Guys,
Need some input about changing the OEM Catalytic Convertergh to a HIGH FLOW Catalytic Converter. What is the consequenses and pros about this ?
Thanks guys

[Lugi20]

I don't know of any high flow cats for our cars, but then again I haven't really looked around.

Why are you interested in doing this? Gains?

[trexturk]

well thats what the downpipes are. They replace the 4 stock cats and put 2 high flow cats.

[channad]

If you change DPs, don't you have to do the requisite chip? I thought I read that somewhere.

[b00st]

If you change DPs, don't you have to do the requisite chip? I thought I read that somewhere.

no you don't.

[tadhgbrosnan]

Danny at Fast Intentions advises customers to reflash the ECU after DP installations. Otherwise, you run a greater risk of blown cats. I don't know the Xs and Os of why, but having researched various DP options this was one point I made a mental note of.

[b00st]

a) does not have to do with b)

the real benefit is it helps with the car to see gains...gain maximum potential and certain softwares also have anti-cel software running...some do that others don't. i can't recall anyone saying you must run a chip if you do DPs on any vendors website. but if your looking to maximize potential/efficiency...then yeah go ahead.

[tadhgbrosnan]

OK, I found the exact thread. It was Dodge2Dub's car. Having read it again, it appears as if a bad manifold may have contributed to both his cats going bad. BUT....the second posting in the thread mentions the DP/ECU point I referenced. Fast Intentions advises an ECU tune after DP installation. FWIW, I spoke to Brent Labree about a month ago and I asked him about this; he said the same thing.

http://www.audizine.com/forum/showthread.php?t=185782

[initiala4]

the part about blowing cats isnt about the ECU. I think what Danny meant is for them to take the CEL part out. Some cats have the wrong load on the cats while some do. When they have the wrong load, the CEL will shoot up. Make sure you get a catback exhaust system with the high flow cats.

[neo]

Thank you guys

[jeremy@matrix]

AWE DPs/high flow cats;

AWE Tuning SS high-flow metal core cats/downpipes for B6/B7 S4 6speed
$1899





http://www.awe-tuning.com/pages/shar...ust&IL=b6s4dps

[37doc]

I have the AWE DP's and can say they are great, build quality , support, sound , all great. The car sounds VERY aggressive.

[91gl]

damn, awe's dp's are expensive. FI's stainless dp's are still only 1550

[tadhgbrosnan]

Brent Labree quoted me $1250 for a set, and Mark at Autospeed quoted me $1200.

[channad]

a) does not have to do with b)

Posted by Dodge2Dub:

"Well, I just got my car back yesterday and it turns out that I burned through both CATS in three months!! The passenger side CAT was completely hollow and the drivers side CAT had a 2.5 inch opening through the honeycomb!! I also had pieces of the CAT lodged in the exhaust pipes.

With that said, FI completely took care of me and rectified the problem right away. We have come to the conclusion that the car runs lean at first due to the gained efficiencies causing the CATS to become super heated. The ECU responds by enriching the system and you end up with a hot/cold scenario that results in dead CATS. Also, I'm sure that the 91 octane isn't helping.

We believe that the cure is to make sure you are running software that compensates for the gained emissions efficiency, especially if you are only able to get crap gas. Personally, I'll be running GIAC within the next few days."

[jeremy@matrix]

Posted by Dodge2Dub:

"Well, I just got my car back yesterday and it turns out that I burned through both CATS in three months!! The passenger side CAT was completely hollow and the drivers side CAT had a 2.5 inch opening through the honeycomb!! I also had pieces of the CAT lodged in the exhaust pipes.

With that said, FI completely took care of me and rectified the problem right away. We have come to the conclusion that the car runs lean at first due to the gained efficiencies causing the CATS to become super heated. The ECU responds by enriching the system and you end up with a hot/cold scenario that results in dead CATS. Also, I'm sure that the 91 octane isn't helping.

We believe that the cure is to make sure you are running software that compensates for the gained emissions efficiency, especially if you are only able to get crap gas. Personally, I'll be running GIAC within the next few days."

What cell count cats are FI using?

[jeremy@matrix]

damn, awe's dp's are expensive. FI's stainless dp's are still only 1550

It's because they fit so well, include the highest quality metal cats, are true pieces of art, their service is unmatched, etc....

You always seem to get what you pay for.

[bhvrdr]

Posted by Dodge2Dub:

"Well, I just got my car back yesterday and it turns out that I burned through both CATS in three months!! The passenger side CAT was completely hollow and the drivers side CAT had a 2.5 inch opening through the honeycomb!! I also had pieces of the CAT lodged in the exhaust pipes.

With that said, FI completely took care of me and rectified the problem right away. We have come to the conclusion that the car runs lean at first due to the gained efficiencies causing the CATS to become super heated. The ECU responds by enriching the system and you end up with a hot/cold scenario that results in dead CATS. Also, I'm sure that the 91 octane isn't helping.

We believe that the cure is to make sure you are running software that compensates for the gained emissions efficiency, especially if you are only able to get crap gas. Personally, I'll be running GIAC within the next few days."

Their comments make no sense since as we all know the S4 chips do not even require an exhaust upgrade and GIAC doesnt sell exhausts so it's highly doubtful they "tuned" for every exhaust out there and neither did APR and Revo. In fact some chips may even create higher exhaust gas temps then stock. The guy burned through his cats because FI uses cats that are simply OK in quality. Plenty of non chipped labree, FI, and even milltek cats have failed on both stock and chipped cars.

cheers! mike