Hello

I just bought a 2011 ford focus 1.6 ecoboost 150hp. I feel there is lot of engine noise/growl entering the cabin in city driving around 1500-2500 rpm. It gets quiter at speed. There is not much road or tyre noise

That would seem about right.

The poorer the spec of the car the less sound insulation so if noise bothers you much then you need to always go for the top of the range. If you already have the top spec then you need to turn the radio up.

On a Focus MK3 there is no difference in sound insulation between trim levels or spec. All trim levels have the exact same sound insulation.

On a 1.6 ECOboost the engine noise is completely normal. The 1.6 ECOboost has a Sound Symposer (like the MK2/MK2.5 ST/RS and the MK3 ST).

The Sound Symposer is basically a box with a membrane that is connected to the air intake. The membrane enhances the intake sound and feeds the enhanced intake sound to the cabin through a plastic hose. The engine sound inside the cabin is pure artificial.

The Sound Symposer can easily be removed. Symposer delete kits or plugs are offered by several suppliers like for example Colins Performance or Pumaspeed.

From the MK3.5 onwards the Sound Symposer was discontinued and superseded by artificial engine sound generated by the audio system.

Thanks for the help guys. I own the top end Titanium X. It must be the Sound Symposer. But I ain’t gonna remove it. I like the sound inside, it feels sporty.