No-one replying here, so I'm quoting from another thread.................
silverbullet wrote:Use an Apollo filter (enclosed cone) and connect to the snorkel to feed the engine cold air and keep it quiet.
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The best way to have a quiet engine is not to let the noise get out in the first place. That means having a sealed and noise tight inlet air tract all the way from the air intake in the side panel, down through the snorkel pipe, through the filter and back to the engine. There is no particular problem with K&N filters except they are usually unenclosed. Fine on a petrol engine if you want a particular sound, but a dead loss on a diesel. As Silverbullet says, K&N do an enclosed version you can connect to the snorkel with a bit of flexible ducting like this
http://www.autosiliconehoses.com/silico ... tings.html" onclick="window.open(this.href);return false;.
Apologies for banging on about this again!
It will be very difficult to soundproof the engine bay to achieve similar results.