K&N air filter for L400
Posted: Sat Dec 05, 2009 12:02 pm
I wanted to put a K&N air filter in my L400, so after some searching I came up with 2 filters that have been reported as fitting well and are being used, one is not available here in North America for some reason that im not sure and the other fit well. but not perfect, the flaw is that the air box off the turbo doesent just suck in air from the top, but also from the back, so it needs some modification to either the top of the air box OR an adapter made for the filter, I could have easily fixed/ adjusted the top of the air box, but if it ever came loose or any sealant came off, I fear what that would do to the fins of my turbo .
so I made the top section so that the only air that is being pulled into the turbo is from the center of the air filter and I put a black RVT sealant around the edges to ensure it would stay in place the top section was a bit ugly but it was a first draft/prototype but works well and does what its designed
once that was in I realised that the other flaw is the bottom of the air box is waffled and the bottom of the air filter is rubber so if its not on PERFECT, then unfiltered air will still get into the system.
So I wanted a Bottom plate, perfectly flat for a good seal, and a edge around it to hold it firm,
The nice side effect of the top and bottom plates is it builds extra pressure on the seals on top and bottom and ensures that only air that has been filtered with the air filter will get to the turbo, with out the plates , using a K&N filter allows Un filtered air into the turbo and intake...
I Really do notice a difference in power with the air filter and even with the work that came with it, I enjoyed the job , if you arent able to make the plates with aluminium, im sure that plywood or another material wouldwork well, just make sure you seal the edges of the top plate .
Noel
so I made the top section so that the only air that is being pulled into the turbo is from the center of the air filter and I put a black RVT sealant around the edges to ensure it would stay in place the top section was a bit ugly but it was a first draft/prototype but works well and does what its designed
once that was in I realised that the other flaw is the bottom of the air box is waffled and the bottom of the air filter is rubber so if its not on PERFECT, then unfiltered air will still get into the system.
So I wanted a Bottom plate, perfectly flat for a good seal, and a edge around it to hold it firm,
The nice side effect of the top and bottom plates is it builds extra pressure on the seals on top and bottom and ensures that only air that has been filtered with the air filter will get to the turbo, with out the plates , using a K&N filter allows Un filtered air into the turbo and intake...
I Really do notice a difference in power with the air filter and even with the work that came with it, I enjoyed the job , if you arent able to make the plates with aluminium, im sure that plywood or another material wouldwork well, just make sure you seal the edges of the top plate .
Noel