65GGvert

My L82, 4spd 78 Silver Anniv exhaust sounded great, but had a loud rattle at idle. The muffler shop found the catalytic converter had disintegrated internally. They removed it and put dual exhaust with Flowmaster mufflers. It still sounds good at idle, but has a tinny sound at certain rpms and when you let off or downshift, there's a sort of gurgling sound like it's about to backfire. Not a good gurgling, it's sort of tinny. The smog pump is still connected, would removing the belt help? Do I need something else to make it sound better? Any help appreciated.

Mikes*Corvettes

As you have removed the cat,
i assume you have no issues with emmission testing where you live.
If this is indeed the case,
if it was me i would consider headers and a crossover pipe next.

69elky

Balance tube/crossover pipe the very least should produce a better sound plus give you a little more HP.Then as mentioned before me Hedders as long as you do not have to get checked for emissons.I have hedders a true dual exhaust system and for mufflers I purchased from Corvette Central a pair of their mufflers designed for the L 82,not sure if still marketed as such.This is the first replacement mufflers since I bought the car new in 79.But they have a nice mellow sound to them.Later Geno

holley505

if you can go without the CATS... go with the mid american chambered exhaust... sounds good and is cheap.

you could also add a H-pipe to this.

Ironcross

Dump the flowmasters, normally the source of the tinny sounds. Very cheaply put together with out any deadening material and to most has a horrible resonance. A much better sound is from the Dynomax series of mufflers and flows as good as any on the market. ...