Mufflers VS Catalytic converters

[davepl]

Originally Posted by BigRed76

Fuel injection with no cats will do you better than carbureted with cats.

Not actually. I have all three:

- Carb'd car with a cat ('75 Monte factory)
- Carb'd truck with no cat ('70 GMC)
- EFI car with no cat ('69 Camaro ZZ502 BS3 Sequential EFI)

The EFI car still smells like raw gas. It runs at about 14.6:1, but to get near stoich at idle with a cam in a motor like these requires a lot of extra fuel that winds up getting in your girlfriend's hair.

Now a poorly tuned car with cats will stink like sulfur dioxide, so there's no substitute for properly tuning the thing. But properly tuned, cats get rid of the raw fuel smell.

Maybe if gasoline still smelled like it did in 1970 I'd be OK with it, but it doesn't.