Exhaust questions on a 76, California model

[Healeyalt]

I'm considering various changes to the exhaust system. I bought the car last Fall and I don't know anything about changes made to it by prior owners. It looks like not too many years ago Midas re-did the exhaust, including an aftermarket CAT.

Question: Did the original CAT on a 76 have a sensor attached to it? In one of the pics in my 76 service manual it looks like a sensor going to the CAT. The one currently on the car doesn't have any sensors. If originally there was a sensor attached to it, I wonder what they did with it?

If I replace the CAT with a straight pipe (you know, for off-road use in Michigan!), will it be un-reasonably loud with just the MIdas muffler on it or should I try to replace the CAT with a "mini" muffler? The CAT on it is only about 9 and 1/2 inches long from flange to fleange.

Any one willing to share their experience with such changes is greatly appreciated.

Thanks

Gary

[John Coffey]

The original sensor was probably a temp sensor that triggered a warning light on the center console. Cats don't normally do much for sound reduction.

[rcb280z]

Gary, I ran straight pipe while in Vegas with a super turbo muffler and loved the exhaust sound. Now that I'm back in California I had to install a new cat and also replaced my muffler, a new Magnaflo. The exhaust definitely sounds quieter. I installed the cat about a year before I replaced the muffler. Sounded quieter after that but there was no change when I replaced the muffler.

[280~Master]

I love mine with 2 1/2 pipe with a glass pack/fart can on the back. The sounds is wondedrfull and gets alot of looks on Saturady car nights here in Savannah.

[Healeyalt]

One more question, if I get rid of the CAT and go with a straight pipe back to the muffler, do I still need those heat shields (the ones on the exhaust pipe itself and that large one above where the CAT was).

From my experience with other vehicles, sometime those shields can vibrate and resonate sounds creating an iritating noise.

Thanks

Gary