Mustang SLP Catted X-Pipe: Will it pass emissions?
 

Im looking into getting the slp x-pipe with high flow cats and I live in Texas so i have to pass emissions tests. Will the high flow cats pass? I have heard they wont... Also, with slp axle-backs, will it be much louder? I had an off road h-pipe, but it was a little too loud. I need something slightly more tame. Will the high flow cats make a big sound difference over the stock ones?

RE: Mustang SLP Catted X-Pipe: Will it pass emissions?
 

Slp loudmouths and a x pipe will be louder for sure. Especially if you were to go offroad. Which it looks like you don't want to. Not sure that the loudmouths would sound good with an x,jmo.
I wouldn't count on high flow cats being louder than stock ones we have. You said you already had an o/r h? How often are your emission tests on a new vehicle? might want to just go offroad h or x and switch up a little before its time.

RE: Mustang SLP Catted X-Pipe: Will it pass emissions?
 

I have the SLP catted X pipe, in AZ don't need emissions testing for 5 years on new cars but I can tell you this, The car definately emits more fumes, you can smell it !![:'(] If emissions testing is an issue I would go with a X pipe that retains the stock CATs, I got long tubes so I couldn't do that but if just adding an X-pipe I wouldget one that works with the stock CATs, I believe Hooker makes one, not sure who else.

RE: Mustang SLP Catted X-Pipe: Will it pass emissions?
 

There is a diff. in sound, def. noticeable w/ high flows cats. I ran the catted X w/ no muffler(loudmouths) for a little and really liked it. LOud but in a good way. Not obnoxious like the O/R pipe which I too thought it was too loud and took mine off. The catted X is a nice medium and depending on what A/B can be quite loud. If, as is this case it's the loudmouths it will sound a lot louder than stock. Not sure if it will pass emissions though-you can see right through the cats. May I suggest bassani? I had the catted bassani X. 1. It's got a better crossover. 2. It's got the highest flowing cats. 3. It's a good amount cheaper than SLP.

RE: Mustang SLP Catted X-Pipe: Will it pass emissions?
 

If its any help i had a frpp x pipe ,just a bolt on kind that uses the factory cats& can say they do nothing for volume, just tone! I recently got the bassani catted X andwow what a difference much, much louder , but not as bad as an O/R pipe! totally worth the money IMOhttps://mustangforums.com/micons/m9.gifas for inspection ... if your state does the sniffer test you wont pass w/ high flows

RE: Mustang SLP Catted X-Pipe: Will it pass emissions?
 

Any particular reason that they shouldn't other than maybe the cats not being OE and the car is still within its original emissions warranty period? Other than that, all I'm aware of is that aftermarket cats need only last 25,000 miles instead of 50,000.


Norm

RE: Mustang SLP Catted X-Pipe: Will it pass emissions?
 

IF your testing is along the same lines as California then no you will not pass. The substrate that is used in the aftermarket cats is different than the O.E substrates that came on the car. Some of them are OBD II compliant and you MAY pass , but even then its still likely you will not because of the "honeycomb" used. Plus, you definately won't pass a visual if they do those in your state..I've been down this road..Now , I have a "friend"....:D

RE: Mustang SLP Catted X-Pipe: Will it pass emissions?
 

Aftermarket cats dont do much for pollution asthe OEM ones do ...magnaflow claims to be OBDII compliant ,so they could possibly pass a sniffer test it all depends on the standards of your states inspection. Id just put the factory pipe back on when that time comes, then switch back!