I have an 85 GSL that has had exhaust mods for performance reasons.

Engine runs great, and is very fast.

However: exhaust is now significantly louder with essentially no cats, particularly in the low frequencies.

I need to get the exhaust worked on in order to pass smog anyway in CA, but would like to put in sound dampening material in appropriate places to deal with the low frequency sound that currently drowns out conversation, radio, cd--basically any reasonable level of communication inside the vehicle.

The PO had put in very nice aftermarket speakers and head unit, but they can't really be enjoyed very much at this point.

Has anyone dealt with similar issues?

Any suggestions on best approach to resolve it?

Thanks!

 

Found the relevant thread:

https://www.rx7club.com/interior-exterior-audio-26/sound-dampening-information-151598/