Its fair to say there is a lot of BS written about air filters which is impressive seeing as they do a relatively straight forward job – filter air used by the engine so that it doesnt suck in crap – hardly rocket science.
However they need to work, suck in particulate matter into an engine and it will create all manner of issues so manufacturers always err on the side of caution with paper filters that do a great job of filtering out particles but they do this by filtering out everything else including air so they are usually a good area to upgrade for any engine and the McLaren is no different.
For years we used the BMC filter for this but over time we decided that it was a compromise in terms of function with its oiled use but with the OEM filters now massively expensive a combination of a performance upgrade together with a lifetime usage needed we have designed our own.
Our filters, made exclusively for us by Ramair, are a dry fitment, no oil at all and provide a decent increase in both airflow and sound with a noticeable increase in induction sound as well as an improvement in initial throttle response – that little snap you get from the first pressing the accelerator. We wont claim any power increase as frankly its marginal and we wont get dragged into the BS of it all but its a proper upgrade and with a lifetime fit you’ll save money straight away.