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Section Seven - Fabricating the Stock Air Tube

The factory air tube will need to be shortened by 7-1/2 inches.


Place the factory air tube on your workbench with the bellows end to the left and the 90-degree bend end to the right.  Find the PCV hose nipple and measure 2-1/4 (Two and one quarter) inches from the center of this nipple to the left (toward the bellows end).  Please measure this again.  One more time, please measure it again. (Measure 3 times, cut once rule!)  Now cut the air tube at this measurement with a hacksaw. Try to make this cut as straight as possible, not like me.


Your air tube should now be cut in half. Take the end on the left (the end with the bellows) and measure 7-1/2 (Seven and one half) inches from the cut you just made to the left toward the bellows. Mark this location.  Measure this a few more times just to be sure. You are going to cut this 7-1/2 inch section of air tube off. When you are done you should have about 1-1/4 (one and one quarter) inches of smooth air tube left just to the right of the bellows.  OK - Cut! - Straight!


Now you will have to reattach the left piece with the bellows to the right piece with the 90-degree bend. You will do this by cutting a 2 inch long piece of 2-1/8 inch inside diameter stainless steel exhaust pipe and using it as an inner sleeve between the two pieces of the air tube. 


One inch of each end of this sleeve will be fitted to the ends of the air tube. The inside of the air tube is smooth, but trust me it is not round. You will have to grind and remove some material from the inside to a depth of 1 inch in order to fit the sleeve. I used a cone shaped stone grinder attached to my electric drill to do this. Be careful because the material comes off quickly and you want this to be a tight friction fit.

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