cat converters

[94HeavyChevy]

i have a 94 caprice with a 5.7L V8....i have duel flowmasters but i have the delta 40 series...i want some more tone from the exhaust...can i take out the converters without causing problems with the back pressure??? and will this make any noise differences?

[silicon212]

Originally Posted by 94HeavyChevy

i have a 94 caprice with a 5.7L V8....i have duel flowmasters but i have the delta 40 series...i want some more tone from the exhaust...can i take out the converters without causing problems with the back pressure??? and will this make any noise differences?

It won't affect your tone whatsoever. It might affect the performance of the engine (in a negative manner).

[CD Smalley]

You 'll also end up setting codes in the computer.

Do you still have the stock resonators behind the mufflers?

[PeteA216]

Originally Posted by silicon212

It won't affect your tone whatsoever. It might affect the performance of the engine (in a negative manner).

I beg to differ... in my '84 caprice I put on a 40 series flowmaster muffler on, but got minimal sound difference from the stock muffler. I hollowed my cat and got a significant difference in sound. It gave it that nice Flowmaster rumble. As for performance, it didn't seem to affect much, at least nothing noticable. For you it may affect the engine negatively, but I can't be too sure seeing that you do only have the OBD1 which in my opinion is fairly forgiving in what can be done to an engine without screwing things up.

[PeteA216]

Oh another example that just hit me... a buddy of mine has a '95 Ford Firebird, and he hollowed his cat with a completely stock exhaust system. It reduced the engine's power until he played with the o2 sensor thats attached after the cat(I have no idea what he did... all I see is a bunch of wires wrapped in electrical tape), but did give the exhaust a little bark.

[silicon212]

Yes, mine is OBD1 as is the '94.

Remember folks - if you live in the United States, it is against the law to hollow a cat.

[PeteA216]

Originally Posted by silicon212

Remember folks - if you live in the United States, it is against the law to hollow a cat.

True, don't bother with it unless you know what your doing and/or tail pipe "sniffers" aren't used in your local state inspection. No matter what it's still illegal, it's a matter of getting caught.

[ISmellRubber]

The 50 states regulate messing with the cat on vehicles.....the computers will sense the cat has been tampered with even pre-cat O2 sensors this can cause driveability issues by how the ecm will adjust the fuel trim ( long term and short term). There is no problem with eliminating the mufler and resonator, modifiying the exhaust pipe diameter headers and things like that....but blowing smog out an old V-8 is not what I call a sound idea.

"you ever wonder where the idea for "smoke on the water" came from?"