I have to get emissions and I'm trying to figure out the cheapest cats I can get to put on my Z28 with SLP LT headers and Y-pipe. I've gotten confused and have seen some searches here and on other sites say to get Carsound cats like 94109, then I've seen where they are too long?

Can anyone tell me for sure that 94109's will fit or if there is a different part number that will?

If there isn't any idea which sponsor has the best deal on cat's that will fit?

 

Be careful about using longtube headers and passing emissions. Different states have their own type of testing. Ohio for instance, just changed the testing method. About ten years ago we had a test system called AIMS. Most service stations and small automotive repair shops were AIMS certified testing facilities. The test was a joke really. I can remember (I was about 17 at that time) driving up to my local ma & pa shop for the AIMS test and all the mechanic did to my 1984 Camaro was:
-open the fuel door and visually check for a fuel cap
-kneel down on the ground and look for a catalytic converter
-pop the hood and check for proper emissions equiptment in the engine bay(EGR valve, air cleaner, valve cover breathers, yada yada yada....)
-check for "check engine" or "service engine soon" light
That was it. Then Ohio changed the system to a tailpipe emission testing during idle and at various speeds on a chassis dynometer. They also did visual checks for gas cap, and catalytic converter/s. The gas cap was also pressure tested. Ohio has since changed the test method again. The test now is an OBD-II PCM test as well as visual inspection. With the OBD-II test, the car's PCM is scanned for error codes. As long as the PCM is tuned well then almost anything can pass the code test, but the visual test is where they get you. If you dont have the proper emissions equiptment they won't even let you test. Replacing the factory catalytic converters is allowed only under certain circumstances:
car must have 50k miles or more OR
original catalyst was damaged or faulty

It is a Federal offense to relocate or tamper with emissions equiptment. All longtube headers move the OEM cat location; therefore, they are illegal in all states. But...your state or county may be very flexible. I would check with some local guys that already modded their cars and see what their experiences have been.

 

Wow, I will keep this all in mind, headers will be on the way shortly for the TA

 

I believe they are 11" in overall length to fit properly.The only place I could get them was random or dynomax power cats to get the right length.Since the originals were random and failed,I got the dynomax powercats in 3" diamater metalic and am very happy with them.

 

Cut the stocks ones pipes and bolt them on for the test. Then take them off.

 

yeah if you are worried about emissions the LT's will keep you from passing anyways, because you are having to change the position of the cats, if i remember correctly.