JLT RAI MAF adapter fix with pics

[Octoberlizard]

I know there has been posts about the fit between JLT MAF adapter and stock maf housing before, just wanted to show my approach to the issue. The first pic shows the gap between the two bolted together. Most of it was due to the bushings in the stock housing being higher than the sealing surface. I believe they were designed that way because of the thickness of the seal on the maf screen. I felt like the gap was borderline as far as just using sealant to fix it, I didn't want to take any chances of unfiltered air reaching the engine. I used a flat file to make the bushings flush. It was a huge improvement but there was still a gap due to warping. Second pic- I used 150 grit on a flat table. I gripped the housing at the very bottom and moved it in a figure 8 pattern to keep it as even as possible. 3rd pic- showing the high spots after a couple minutes of sanding. I continued until the entire sealing surface was uniform in color. I did the same for the billet JLT piece. Even though the instructions say it's perfectly flat there were high spots from the grain of the cut. I cleaned everything up and applied a very thin layer of gasket maker to the surface before assembly. In my opinion there it's no way to achieve an airtight seal between these two pieces without a gasket or sealant no matter how flat they are. Last pic shows the finished product. No more light shining through. I would encourage anyone who didn't make a gasket or use sealer, to remove the filter and shine a light inside the tube. If you can see light then you have an air leak. I hope this helps someone.

[768MPH]

I had the same gap, I just used RTV to bead the mating surfaces, attached them, and "caulked" it like a sink backsplash on the inside and made a tight seal.
Less invasive but both approaches work.

[Octoberlizard]

Yeah I thought about doing that. I was just worried that the rtv may break loose over time. Especially with the bushings higher than the sealing surface there is no compression between the two pieces except at the corners where the bushings are. I can definitely see that rtv would work. But if it failed you wouldn't know till after the fact most likely. Thanks for your reply.

[bigtrain]

i did the rtv on mine i had a gasket i made from fel pro material but the gap was still to large put a lil black rtv fixed it quick

[SchwermoRacing]

I though that space was to allow room for the mesh piece that came with the stock intake to cut back on air turbulace before the MAF.

[Octoberlizard]

Yeah it is for the screen on the stock unit. Although it may cut down on turbulence, it was put there to catch debri. If something such as a blade of grass lays across wire of the maf it changes the resistance value and will give false readings to the pcm. The debri usually gets in the air inlet during a filter change. I have seen this happen several times personally.