I have a MY00 estate and have just fitted a 3.5 inch back box. I'm not sure if it is because it is the estate but it is terribly loud/bassy in the car now, unbarably so on the motorway.

Does anyone have any idea if putting some sound proofing on the boot floor would help? or any other way of making it a bit quieter in the car. It sounds lovely from outside!!

Thanks,

 

I have a wagon with the exact same problem.
It used to have just the magnex rear box, but Ive now de catted the downpipe and exhaust and have an ra(resonated centre) middle section.
Its a bit louder on full boost but much less droney... or boomy.

*****

 

Yes, sound deadening on the boot floor will help a bit, do the spare wheel well too, it rings like a bell.

 

i put two layers of thick carpet underlay under the boot carpet to quieten down my 6x4 oval

 

I had same problem on my Wagon. A Magnex resonated centre section did the trick. Sounds bl00dy marvellous now.

 

its a wagon thang !!!!!

i had the same problem but i had an afterburner bb,,god it made me feel sick,,literaly i felt sick,,the air in the cabin seemed to flutter,simalar to a loud base tube.

i cured it by changing the bb to an afterburner stealth and also fitted a magnex resonated centre section wich cured it and sounded purfect.

all the best with it

roy

 

I have an HKS super drager with a resonated HKS centre and HKS decat d/p, i get no cabin drone and it gives a beautiful rumble poodling round but what a howl when you let loose, brilliant zorst IMHO

 

My wagon has a Scoobysport box and I don't find it too bad, certainly not as bad as some of the posts above.
It has got a few layers in the boot (had them from when I got it so I'm not sure what is standard) but its got 5mm plywood over spare tyre well and then 15mm of a dense fibrous material, guess that must help.