My '83 12A still has the original catalytic converter. It's starting to get a rust hole in it. In addition, the insides have rusted/burned out of the oiginal muffler. I'm thinking of getting the Bonez cat replacement pipe and Borla Pro-XS muffler (least $ I can spend, I think). Any opinions of how loud this would be? Also, could I just leave the tube form the air pump to the cat open or would I need to clamp it or remove the air pump altogether? I'm not ready to do the rat's nest removal yet...

Alternative would be Bonez high flow cat and muffler or Racing Beat muffler.

BTW, no smog checking here in NC, but we're supposed to have all original smog equipment. For that reason I'm hesitant to go with a full header, etc.

Thanks! - David

 

Well, the full header they will never notice unless the police look under your hood. The straight pipe will be louder, even a presilencer will be louder than the stock cat setup. I'm running the racing beat setup from front to rear, love the way it sounds, but it is louder than most cars on the road even with the presilencer and muffler.

Be forwarned most after market headers will require the removal and blocking off of the ACV on the side of the engine, so you might end up removing the ratsnest anyway ( fun and easy) If you do go that route, I've got an extra set of block off plates I do not need from racing beat.

 

I have the bonez cat on a donor 12a car right with the stock muffle. It is only slighter louder than the oem cat. There is a provision on the bonez cat to put the air tube back on. You do not want to remove the air pump or tube if you are staying with a cat because it will be ruined in a short time without the air injection to it to get rid of the unburned crap. Leave the rats and everything like you have and it will just be a bolt on replacement for the cat.