DJAngelicon

Hey guys I was just wondering is it worth getting a RB down-pipe to replace my crack Cat? Will I notice some HP Gain since I hate the sound of the crack cat. Sound like farting under my car. It also make my car pop alot in the freeway I am also feeling I am losing performance as well that way.

rmriggin

Go to an exhaust shop that will put in a "test pipe". If you do not already have the rest of your emissions equpment removed then it would be necessary or advisable to have the air pump pipe that connects to the cat plugged off. So... When do you no longer need to pass emissions? If you no longer have to pass emissions follow this guide http://maz_tutorials.ten15.net/

REmoving all the emissions equipment will free up weight, make the engine bay look cleaner, free up some HP, and simplify things. I have an intake that has already had emissions removed and blocked off. I may even still have the old carb that has had the emissions removed from it (but it has a bad accelerator pump). You should do a search, look for pics, or maybe sterling could provide some pics of what needs/can be plugged on the stock carb.

onslaught_81

wouldnt just removing the air pump be enough? or just plugging it up till the next emmisions test, when you put a cat back on and the airpump reconnected? i didnt think you hadto remove the whole rats nest just to temporarily remove the cats...

ChasRX

I have kept my rats nest and air pump while using my RB full street port exhaust. Just let the air pump blow to nothing.

Swap back the original exhaust and cats on the day of inspection.

DJAngelicon

last time for emission I will no longer need to have emission test on my 81.

ChasRX

Mines an '81 and in NC they don't actually test, but they'll look for a catalytic converter to be in on the exhaust and inspect for exhaust leaks. I keep the original '81 exhaust manifold and exhaust with a single cat welded in the mid pipe. I run the air pump to the cat-tube.

DJAngelicon

I see ya have visial inspection but we don't have that here so is not much of a problem. If anything I will get a set up later on when I do a bigger project on my car. Right now this damn crack cat is horible and is just as bad as not having a cat at all. So oh well, hehe...