Here is a strange one for you guys thinking about, of have done an oil filter relocation. I changed my oil & filter over the weekend, only to discover when i cranked over the engine to have no oil pressure! I decided to fit a K&N filter I had had for some time, after refitting the old one back on, BAM!, Pressure again.. The only thing I could see, was the Cusco That I had on there in/out filtered section is pretty much flat, while the K&N ( as well as most Ryco etc) are recessed, with about a 10mm gap. this must cause cavitation or something and interrupt flow. I now have a HKS which is also fine, just a bit smaller. Just something to consider when doing this upgrade, I only had the Cusco initially as it is magnetic and i thought it wouldn't hurt to fit one after tapping the block for the turbo.