6637 Intake

The stock air box on the 7.3’s is not the greatest in the world. Its well known for not sealing well and letting dust in. Mine had the usual broken catch for the front latch and the previous owner had put in a K&N drop in filter. After shopping around and reading up I found a great way to improve filtration and airflow cheaper than an aftermarket intake setup. This goes by a couple names, 6637 Intake, or home made tymar, but its basically the same thing. A NAPA FL6637 attached to the stock intake tube and that replaces the stock box and filter.

Click on the images for a larger view.

Notice the side clamp in the pictures. The plastic bar that it clamps onto and pulls the lid tight breaks off the air box. The lid then wont seal tight. I was not real happy about that but am going to replace the turbo wheel with a wicked wheel in the near future.

Next I undid the worm clamp from the intake tube to the lid and it just lifts up and out. There are a couple bolts holding the air box that the lid clamps to and it came out seperate from the entire battery box.

I went ahead and removed the battery to make things a little easier to get to. In the pictures you can see the AIT sensor laying there. I zip tied it up near the master cylinder.

It is a snug fit but the new filter fits in were the old air box was. I test closed the hood and it did not squash anything but its real tight fit and does not move. Jeff and I are working on an idea to make a mounting bracket that will bolt into the stock mounting holes. The bracket will have a 4 inch tube welded into it so all that would be needed was the filter and one worm clamp to mount it to the bracket.

I got a 1 foot section of 4 inch galvanized exhaust tube from NAPA for $7.00 and they even cut it into half for me. I took one of the 6 inch sections and filed and cleaned the ends up then spray painted it black. It was a snug fit but it fit into the end of the filter. I used a worm clamp there then plugged the other end into the factory intake tube using the stock clamp.

Some people have used PVC or ABS connectors from the hardware store to connect the filter to the tube, or even got the filter to fit right into the tube.

I felt a little difference with my butt-dyno but the impart thing is that Its nice to know that I’m getting good filtration now. It sounds great also. The turbo whistle is really there along with the woosh. Total price: FL6637 $38.00, 4 inch tube $7.00, Worm clamp $1.00 = $46

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