The AA are pointing out that cars cause more pollution at 20mph than 30mph, and are using that fact to launch their Fuel For Thought campaign (The Argus, January 29).

The fact is, there is a need for car speeds to be reduced in our crowded cities, in comparison to say 20 years ago.

However, the development of the car engine has not kept pace with that change. It simply isn't capable of doing what it should be able to do (ie. low speed economy) but it is capable of doing what it shouldn't be doing (ie. 120mph).

It's about time the car manufacturers cast aside the romantic marketing ploys that have high speed capability at their heart and focus on designing cars for the real world where there is a clear need for reduced speed.

  • Graham Howson, Franklin Road, Portslade

Everybody wants safer roads and everybody wants to improve the environment. Fortunately there is a way to achieve both.

A 20mph urban speed limit would save lives immediately and forever.

Admittedly it would take some time before the conservative motor manufacturers get round to improving the performance of their engines so that they have lower emissions at 20mph than at 30mph but it will happen - particularly if they are required to publish the figures in their adverts.

So, improve road safety in our urban areas by introducing a 20mph speed limit. And support the leading car makers in their efforts to clean up the air that we all breathe.

How hard can that be?

  • Max Glaskin, Chester Terrace, Brighton