i never installed any deadening on the floor. i felt there was a pretty decent amount from the factory anyway. thick foam under molded MLV/rubber coming down the firewall, slope, and down to the floor. on the floorpan was 2" of denim underneath the carpet and some spot CLD.
i wanted to reduce tactile feedback from midbasses in the kicks. i took a suggestion from a local audio nerd and applied some stuff in the driver/passenger footwells.
two layers of cld, one layer of ccf, and a layer of floating mlv. it took me about three hours.
result? less tactile feedback, only from the lowest notes now. floor feels a little taller. upper midbass response is different so i have to retune that again.
as for the rest of the feedback? try modifying some floormats.
trimmed up the factory floormat, fits much better than the car-go mat i was using. looks better too:
i also tried making some isolating floormats without success so far. i tried mlv, 1" foam from joann's, and a factory cloth floormat. it was worse than just the floormat by itself. if i pressed my feet in, it worked well so the foam was probably too stiff. i tried changing the order (foam, mlv, floormat), with the same results.
i tried mlv+ccf+floormat: also worse than the factory floormat.
double floormats works better than a single floormat.
some day soon, i'll grab some batting or find some very soft foam.
Most of the parking structure at work is “compact car” parking. If I wasn’t able to use my mirrors, I couldn’t do stuff like this: