Installing Dynamat sound deadening insulation

As I continue fitting up the bodyshell with parts and turning this thing back into an actual car, the jobs are starting to jump around a bit from one area to another, so I’m starting to save up my updates so that I can capture one area in a single post. This might mean that posts become a bit more sporadic until I’ve finished a particular area, and then you might see several in quick succession, but I think it’s better to present things this way as “complete jobs”, even if it messes with the actual chronology of the project a bit.

Anyway, here’s a post about Dynamat sound deadening insulation installation. Originally the MGB had bitumen sound deadening glued to the floorpans from the factory, I remember scraping the remnants of this off of the remnants of the original floors the first time I restored my car. That time round, I didn’t really put any sound deadening back in, just some old carpet offcuts that I had found in my parents’ garage, which I put underneath the tatty original MG carpet. The original bitumen material is still available new, pre-cut to fit around the flutes in the floorpans, but with all of the additional noise I’m expecting with this car, I wanted something more substantial in place to try to keep the volume down in the cabin for longer journeys.

I purchased a Dynamat “project pack”, which should provide enough material to cover most areas in a whole car. It gave me good coverage of the main floorpans, footwells and inner sills, as well as the transmission tunnel and heelboard.

The material is fairly easy to cut with a decent pair of scissors and adheres really well, it will not be coming off again in a hurry. The real test will come later, but at this stage it does seem to work well, completely damping any resonance in all of the covered panels.

Bit of a tangent (it’s not worthy of its own post!), but here you can see the new quick-release battery cover I’ve fitted for easier access. It’s a hinged panel with 2 hand-opened fasterers, rather than the original rigid panel that was secured by 3 screws. The number of times I had to remove the panel in the past on this car made me think this will be a good time-saver in the years to come. It was easy to fit, but did require the drilling of one additional hole that also needed an extra “dzus” fastener fitted to it.

Happy with my work, it only occurred to me some time later that the big new solid roof panel I had fitted would very likely also benefit from some sound dampening, so some additional Dynamat sheets were procured to cover it.

Job done. It doesn’t look very original, but all of this will be covered once the full interior is fitted later on, and hopefully is well worth the time and expense if it makes for a more pleasant driving environment.

Just to round things off for today, I refitted this piece of original factory vinyl that sits beneath the handbrake mechanism to partially mask the big hole in the carpet needed for the handbrake to poke through. It’s probably the only piece of original interior trim I deemed serviceable enough to go back in – except for the seat covers, which bizarrely enough are in perfect condition.