"HIGH FLOW" Catalytic converters

[Faster12]

Is there really a such thing. I was looking at some when I came across this little article:

http://www.catalyticconverter.org/ne...erter-&News=89

Just in case you can't use the link, the article reads:

Is there really such a thing as a High Flow or Performance Catalytic Converter?
Read the following story and you might be surprised!




There are many companies on the web today selling what they call a "high flow" or "performance" catalytic converter. We get calls almost everyday from customers wanting to know how much a "high flow" or "performance" catalytic converter will cost for their car. Well this may come as a surprise to some and will really bust the bubble of what some companies are selling, ....THERE IS NO SUCH THING AS A HIGH FLOW OR PERFORMANCE CATALYTIC CONVERTER!! A catalytic converter has no moving parts nor is chambered like a muffler, or have elaborate packing like a muffler. It's interior is not designed to move exhaust gasses along more quickly such as having a spiral core.

A catalytic converter is designed to reduce harmful exhaust gasses...that's all! Basically all aftermarket cats have a ceramic substrate (the guts) that during manufacturing is coated with a solution of platinum, palladium and rhodium. This coating is what causes the catalyst reaction once the converter reaches a certain temperature supplied by the vehicles exhaust gasses. These substrates are made like a beehive honeycomb and are comprised of 400 cells per square inch across their surface. In theory, an aftermarket cat is higher flow than it's O.E. counterpart, because the O.E. converter has a substrate made up of 700 cells per square inch, so the exhaust flow with an aftermarket converter is a little freer, but not dramatically! We do carry a few universal converter numbers that have a 200 cell substrate but they are like I said, universal. They sometimes require extensive welding and cutting of the original exhaust system, so for many applications these are just not practical.


Okay that's it!! There is no Magic "Super Free Flow" Catalytic Converter out there and any company that tries to sell you one is not quite telling you the truth, The sad thing is, there are some web sites claiming they have High Flow Performance Cats, and by the way at a huge inflated price, when in fact all you will be buying is the same converter you would buy anywhere else for half the price. So that's the story in a nutshell. But if you're still determined to find a High Flow catalytic converter or your buddy told you he got one from XXX Auto Parts, try to remember what you've read here and ask some real questions about the product. Like how many cells per inch are across the surface of the substrates or how many grams of precious metal wash coat is baked into the substrate? If it's below 25 say thank you and leave quickly. If the coating is less than a 25 gram mixture the cat will not do the job, and it will set off the check engine light. You might be surprised to find questions like these will throw most sales people for a loop. Most will have no clue what you are talking about, so just be careful. Okay, if you are now totally confused about the myth of High Flow, Go Flow, Mo Flow catalytic converters and would like to talk more about them...give us a call we'd be happy to hear from you.

I posted all this to ask, is it true? Do they really make any difference or is it just a sales pitch?

[SlingShot]

They make a big difference IMO ... I went with SOLO, they are 200 cell single cat and get great sound and power from them. Also by design, you will not get any CEL and bolt right on with no issues. I highly recommend gooing SOLO !!!

[HDRDTD]

Originally Posted by Faster12

Is there really a such thing. I was looking at some when I came across this little article:

http://www.catalyticconverter.org/ne...erter-&News=89

Just in case you can't use the link, the article reads:

Is there really such a thing as a High Flow or Performance Catalytic Converter?
Read the following story and you might be surprised!




There are many companies on the web today selling what they call a "high flow" or "performance" catalytic converter. We get calls almost everyday from customers wanting to know how much a "high flow" or "performance" catalytic converter will cost for their car. Well this may come as a surprise to some and will really bust the bubble of what some companies are selling, ....THERE IS NO SUCH THING AS A HIGH FLOW OR PERFORMANCE CATALYTIC CONVERTER!! A catalytic converter has no moving parts nor is chambered like a muffler, or have elaborate packing like a muffler. It's interior is not designed to move exhaust gasses along more quickly such as having a spiral core.

A catalytic converter is designed to reduce harmful exhaust gasses...that's all! Basically all aftermarket cats have a ceramic substrate (the guts) that during manufacturing is coated with a solution of platinum, palladium and rhodium. This coating is what causes the catalyst reaction once the converter reaches a certain temperature supplied by the vehicles exhaust gasses. These substrates are made like a beehive honeycomb and are comprised of 400 cells per square inch across their surface. In theory, an aftermarket cat is higher flow than it's O.E. counterpart, because the O.E. converter has a substrate made up of 700 cells per square inch, so the exhaust flow with an aftermarket converter is a little freer, but not dramatically! We do carry a few universal converter numbers that have a 200 cell substrate but they are like I said, universal. They sometimes require extensive welding and cutting of the original exhaust system, so for many applications these are just not practical.


Okay that's it!! There is no Magic "Super Free Flow" Catalytic Converter out there and any company that tries to sell you one is not quite telling you the truth, The sad thing is, there are some web sites claiming they have High Flow Performance Cats, and by the way at a huge inflated price, when in fact all you will be buying is the same converter you would buy anywhere else for half the price. So that's the story in a nutshell. But if you're still determined to find a High Flow catalytic converter or your buddy told you he got one from XXX Auto Parts, try to remember what you've read here and ask some real questions about the product. Like how many cells per inch are across the surface of the substrates or how many grams of precious metal wash coat is baked into the substrate? If it's below 25 say thank you and leave quickly. If the coating is less than a 25 gram mixture the cat will not do the job, and it will set off the check engine light. You might be surprised to find questions like these will throw most sales people for a loop. Most will have no clue what you are talking about, so just be careful. Okay, if you are now totally confused about the myth of High Flow, Go Flow, Mo Flow catalytic converters and would like to talk more about them...give us a call we'd be happy to hear from you.

I posted all this to ask, is it true? Do they really make any difference or is it just a sales pitch?

Who is the author? who wrote the article. I'm curious.

[AKA-22]

ok...

[hawk02]

Originally Posted by SlingShot

They make a big difference IMO ... I went with SOLO, they are 200 cell single cat and get great sound and power from them. Also by design, you will not get any CEL and bolt right on with no issues. I highly recommend gooing SOLO !!!

Are the Solo converters installed on your ZL1? On the Solo web site, I just see converters listed for the LS3 and L99. Will these also work on the LSA?

[SlingShot]

Originally Posted by hawk02

Are the Solo converters installed on your ZL1? On the Solo web site, I just see converters listed for the LS3 and L99. Will these also work on the LSA?

Yes, use the L99 for the auto and LS3 for the manual. I ordered and installed the ones for the L99, and there are ZERO issues with them. They made a world of difference in sound and power. Between the Solo cats and Roto-Fab, at 1/2 throttle my tires are just spinning. Next mod will be new rubber ...

[mbober99]

the larger the diameter of the pipe of the converter the more air can flow thru it also no matter what cell size per inch.

[hognutz]

that articale has some good points and bad points.

Almost all the tuners I have been talking too really are pushing off road for the HP levels this car can achieve.

They say the aftermaket quality is just not on par with the OEM and once you reach 650-700bhp which is really easy to do with these cars it is not worth the risk. Even the the aftermaket cat has a higher cell count they cant still plug and fail.

Now many people run them but depending on how hard you drive you car it is food for thought. I have seen one person on this board kill JBA cats alreay on a single track day.


Honesly without some kind of CFM numbers the argument of a HIGH flow cat is just a marketing statment. Even if a cat has a HIGH CFM flow if it is made in china out of inferior materials it can still fail.

[hawk02]

Originally Posted by SlingShot

Yes, use the L99 for the auto and LS3 for the manual. I ordered and installed the ones for the L99, and there are ZERO issues with them. They made a world of difference in sound and power. Between the Solo cats and Roto-Fab, at 1/2 throttle my tires are just spinning. Next mod will be new rubber ...

This is great to know. I was planning to install Solo high flow cats on my 2SS but fell into a good deal on a ZL1 so I traded her in. I thought I was limited to the OEM cats on the ZL1 unless I went the route of LT headers and tune.