Who's running a high flow cat?

[dustin_8907]

Just wondering because I HAVE to... Cops are cracking down on emissions where I live.. I have the universal 3" high flow cat from magnaflow. Just wondering who has one and what kind of power are you guys making on them thanks.

IMO cat=vagina BUT if you have to have one, you have to have one :/

 

[99ECLIPSEGSXDSM]

I have a Magnaflow 3 inch cat that I had in and thinking about putting back in for emission purposes. I personally didnt see a big difference in power but then again I'm only running a big t28.

 

[dustin_8907]

I have a Magnaflow 3 inch cat that I had in and thinking about putting back in for emission purposes. I personally didnt see a big difference in power but then again I'm only running a big t28.

I have a 16g and noticed a difference in spool time and that's about it. No real power loss.. I'm still running the stock o2 housing so I'm going tubular and hope my spool time is a little faster as when I had a test pipe on..

 

[daren_p]

I have two 3" HF cats that I run. One is a typical HF cat from RRE that I now just run for e-tests. Daily I run a 3" HF metal core cat from Vibrant.

The metal core ones are supposed to flow better but aren't as good for emissions. Swapping back & forth, I haven't really noticed a difference between them. Depending on what boost I'm running, I'm typically flowing 56-60lb/min.

 

[dustin_8907]

I have two 3" HF cats that I run. One is a typical HF cat from RRE that I now just run for e-tests. Daily I run a 3" HF metal core cat from Vibrant.

The metal core ones are supposed to flow better but aren't as good for emissions. Swapping back & forth, I haven't really noticed a difference between them. Depending on what boost I'm running, I'm typically flowing 56-60lb/min.

Nice. What kinda price you pay for them? I just got the magnaflow because it was cheap 70 bucks shipped.. May upgrade to a metal core in the future but my power goal is only 350-375 whp.

 

[daren_p]

Nice. What kinda price you pay for them? I just got the magnaflow because it was cheap 70 bucks shipped.. May upgrade to a metal core in the future but my power goal is only 350-375 whp.

The RRE one was ordered from RRE, so whatever their site says is what I payed (it was years ago). Believe they used the Magnaflow HF cats, so its probably the same as what you have.

Unless you get a metal core version for cheap, I wouldn't spend much on it. As I said, when I switch back & forth, I don't notice a difference. Now I haven't done specific back to back tests & gone over my logs with a microscope but in general I do take alot of logs & don't see changes in airflow, spool, etc large enough to notice.

Think I paid $50 for the Vibrant metal core, but believe that was a special price.

 

[RamenPride]

I'm running a "Thunderbolt" high flow cat off of ebay. Currently going for $37.99 on ebay +$10 for shipping. I can't remember how much I paid a few years back, but it works just fine.

 

[ceedawg]

You will definitely fail emissions with the metal cat. It flows like there is no cat there at all. My AMG won't pass emissions for nothing and it has two metal cats!! I would get the one from RRE!

 

[untouchablecc]

I am currently running a Shultz high flow 3inch cat. It came with my exhaust system PA cops will check for that too Ive seen it happen. Thats why I run one. I do not have a price for you but its been on my car 5 years.

 

[daren_p]

You will definitely fail emissions with the metal cat. It flows like there is no cat there at all. My AMG won't pass emissions for nothing and it has two metal cats!! I would get the one from RRE!

Not necessarily true. I have a buddy with the same Vibrant metal core cat I have, on his awd swapped Spyder & he's passed emissions twice with it so far. His readings were on the higher side, but he did absolutly zero prep both times, before testing.

Metal core cats are supposed to work but I believe they require addtional heat (or are harder to get hot enough) for them to function properly.


As for the so called cats on Ebay, half them are just straight through pipe. So will do nothing as far as reducing emissions. Real high flow cats are so cheap now that even a DSMer can get a legit one

 

[ceedawg]

Not necessarily true. I have a buddy with the same Vibrant metal core cat I have, on his awd swapped Spyder & he's passed emissions twice with it so far. His readings were on the higher side, but he did absolutly zero prep both times, before testing.

Metal core cats are supposed to work but I believe they require addtional heat (or are harder to get hot enough) for them to function properly.


As for the so called cats on Ebay, half them are just straight through pipe. So will do nothing as far as reducing emissions. Real high flow cats are so cheap now that even a DSMer can get a legit one

Well I guess MB's are different beasts. Normally most of them especially the V8 AMG Kompressors and non-Kompressors V8 motors have four cats. Ever since I replaced 2 of the stock cats(rear) with the metal cats I can't pass the obd2 inspection for nothing.


I would also suspect hat it would be harder for a OBD2 DSM to pass vs an OBD1 DSM but with these cars I am probably wrong again.


Later on I see you mentioned that they probably don't get hot enough. I have heard that on the MB forums I believe and that could very well be my issue right there. I may have to go back to the asbestos cats. But high flow if I can find some.

 

[daren_p]

Well I guess MB's are different beasts. Normally most of them especially the V8 AMG Kompressors and non-Kompressors V8 motors have four cats. Ever since I replaced 2 of the stock cats(rear) with the metal cats I can't pass the obd2 inspection for nothing.


I would also suspect hat it would be harder for a OBD2 DSM to pass vs an OBD1 DSM but with these cars I am probably wrong again.


Later on I see you mentioned that they probably don't get hot enough. I have heard that on the MB forums I believe and that could very well be my issue right there. I may have to go back to the asbestos cats. But high flow if I can find some.

Not trying to get too far off topic but I assume you did take the car for a nice rip to get it good & hot before the tests? Some places here will just take a car in cold & do an e-test, not allowing for it to warm up properly. I've heard of stock setups failing when all that was required was to get the cat up to proper operating temp.

I went looking at Vibrants site last night & came across a new high flow metal core cat they now sell. Looks like its supposed to work much better then a typical metal core but still flow just as well. Though the price is much higher, selling in the $400-500 range.

As far as OBDII being harder to pass, I think that depends on the vehicle. The newer the vehicle, typically the more advanced the OBDII system is. DSM's being as old as they are, seem to be pretty basic. Link has the ability to show if the readiness monitors are passed for an OBDII scan. On my car, I actually always set the cat monitor & I'm not even using the rear O2 sensor (WB is logged with that input). So it seems 2g OBDII setups are pretty basic, I'm sure if its a newer Benz, the scan is going to be alot more difficult to pass.