Is anybody running a catalytic on their turbo car? If so, what brand will hold up pre- turbo. I am trying to avoid placing my cats after the turbo. How will cats before my wideband affect my air fuel readings? I did a search and read a few posts, but none really answered my questions.

 

What exactly are you trying to do? Why would you want the cat before the turbo?

 

I am trying to place the cats where they will work the best without hindering the performance of the turbo. If the cats are placed too far away, they don't work as well and from what I have read, it is best to avoid any restrictions after the turbo. I currently have two 3" metalic core mini cats that I used with long tube headers on my supercharged setup. They are high flow, low restriction type. I know that with these being large (for a 347) and placed farther away because of the long tubes, they were not working as well. My car would totally fumigate my garage within minutes hot or cold. I leaned out the a/f to the point it almost would not idle and it would still do it, so not a tuning problem. I am trying to avoid this problem when I fab up my turbo exhaust.

 

Moving the cats before the O2 sensors will effect your airfuel readings.

What typs of vehicle are we talking about here?

The only application I can recall of a turbo being after the cat is a rear mount setup?

 

I am building a 347 in an 88 mustang. I have an 80mm ball bearing turbo and an Aem computer with wideband o2. I know that Subaru puts the cat before the turbo on the wrx. My concern is if my metalic core cats will hold up under the extra heat of being before the turbo, or is there a cat like Subaru uses that is designed specifically for placement before the turbo. I would never put ceramic core cats there because I have seen them break into pieces. The other option I thought of was running a single 4" cat in the downpipe to maintain closer distance to the engine. Any experience in running either of these setups?

 

If you don't want to hinder performance of the turbo, don't put cats in front of it! Are you putting them on for law related reasons? Or trying to actually pass an etest? where I live the ministry requires us to have all emissions equipment, so I just run gutted cats to keep the appearance! No hindering of the turbo here lol

 

I only have to pass a visual equipment inspection for state inspection, but I have to pass my wife's sniffer test. If the garage gets fumigated, the smell gets into the kitchen when the door is open. When this happens, she is not happy. When she is not happy, nobody can be happy. (If you are married, you know what I am talking about.) As I mentioned, I want my cats to be fully functional. Is it more of a problem to have a slight restriction before the turbo or after it?

 

When the door is open?

You are going to seriously choke the turbos with the cats. Not to mention moving them to before the O2 sensors will mess with your tune. Moving them will not help your problem. It will most likely make it worse.

 

Best solution would be to forget about the functional cats and buy a set of tubes and fittings to put in your garage door to rout the exhaust outside like a lot of shops use. I would not risk putting the cats pre turbo, have one come apart and mess up a turbine wheel and shaft.

 

The exhaust fumes fill my garage quickly even with the garage door open. This is not a problem with our other cars. When I first put the car together, I fabed up the exhaust without cats. The fumes were very bad then. I worked with the tune quite a bit on my aem. That helped some. Then I added the high flow mini cats. They helped a little. I do not think they are lighting off as well as they should because of the long tube headers or it may be that these cats just do not work all that well by design (flow greater than function.) I would like to avoid making another poor choice on this thing, so still looking for input on what cat and placement people have had the most success with. You already mentioned the reservation that I had with placing a regular cat in front of the turbo as I would like to keep my turbine wheel in one piece.