http://members.shaw.ca/gregtsmith/Drop%20Base.htm

Drop Base Faux Dual Snorkel

Don't worry the orignal Vin 9 307 motor will stay with the car it just won't move it any more... In its place will be a H/O 350 Olds based loosely on the famed W31... just mine will have enough vacuum so that it can run power brakes and A/C.

But you can't run a decent H/O motor without a high rise intake right... One problem the stock air cleaner won't fit...  While I could buy a generic 14" drop base open element air cleaner for $20 from Summit.  I want this to look stock.  So what are you to do.  Get out the grinder, cutoff wheel, and the TIG welder and have at it!

 

TOOLS Needed:

First, here is a list of what tools you will need to complete this:

Welder
Die Grinder
Cut off wheels
Cordless Drill and Drills
Hammer and dolly
Tin snips
Locking pliers and clamps
Band Saw

SUPPLIES Needed:

Old Single Snorkel Air cleaner (2)
Big Flat piece of sheet metal
Filler wire
Body Filler)
Scrap wood (1x6)

Disassembly:

Buy 2 Air Cleaners from Wrecking Yard

  1. Actually all you need is the assembly and a second snorkel.  I scored mine from a early 80s Custom Cruiser and the Snorkel is from a LG4 Camaro

Single Snorkel

Other Snorkel

  1. When you go to the yard take a 12-14V cordless drill and a couple of 1/4" and 3/8" bits and drill out the rivits at the four corners.  I told the yard the that the vacuum thingy looked bad on the first air cleaner and asked if he would through in the second snorel for free... Score! $20

Remove the Base from the Air cleaner.

  1. With a die grinder and a small cutoff wheel dissect the bottom of the air cleaner from the sides.  leave a small lip on the sides so that you will have something to weld to and something to measure from.

  1. The bottom section is scribed with reference marks so that I can reassemble with the same orientation.

The Drop

  1. Make a template for the drop section, the inner section is the diameter of the base the outer is the diameter of the sides.  You join the ends to make a "cone" with the slope the same as a 3/4/5 triangle. In this case the geometry of the cone's triangle was a  base of 3/4", a height of 4/4" and a slope of 5/4" (3/4", 1", 1 1/4").  This will yield a drop of 1" and will enable me to switch to a filter element for a F-Body... which I have been assured will fit

 

Here is the piece.

Weld

Tacked

Continuous weld, ground flat

Fake a second snorkel

  1. You will need to section the second snorkel to make it more "square" like the stocker, Cut it to length + 1/4" (you'll need that for the "lip")

  2. Then cut a "vertical" line after the  budge were it connects to the base.  Do this on the top and the bottom.

.

  1. Now cut a "horizontal"  line to intersect the first cuts.

  1. Bend the wings apart to make the unit "straight".

  1. Cut more patch pieces and weld them in... Grind them flat.

  1. Cut holes for the Vacuum door controller.  Pattern these from the old snorkel.  Take care which way the nipple on the vacuum can points... If that's important to you.

  1. Test assembly.  Nipple wrong... cut grind and fix... Do not  weld the vacuum motor just yet

Bend the Lip

  1. Cut two pieces of wood that are the size of the inside of the new snorkel and the outside of the new snorkel

  1. Place this contraption in a vice and SLOWLY bend over the lip.  Once you have a nice factory rolled edge carefully break away the wood

Attach new Snorkel

  1. Cut a hole on the side of the base directly opposite of the original snorkel.  Use the new snorkel as a guide to scribe the hole and then cut 1/4" - 3/8" inside that scribe.  Slowly, with linesman's pliers bend a lip out the to scribed mark.

  1. Fiction fit the new snorkel.  Hammer and dolly the inside lip "tight".

  1. Re-weld it on at the four spot welds... grind them smooth

Weld on the new base

  1. Tack and the continuously weld the base to the sides

  1. All it needs is a chrome lid and some paint.  I hope it fits. I have about 9 hours of welding and grinding into it so far.  I have tested it on a spare Q-Jet and it clears all of the leavers, cams, springs, and brackets by at least 3/8".  So I'm confident that I could get it another 1/4" lower if I need it..  This is a full 1" lower then the stocker,  I do presently have 1 1/2" clearance with the stock air clearer and the hood (with the insulation) so I'm confident that with this cleaner, my 2" taller manifold should still have 1/2" of clearance.  Famous last words.

    By my calculations, if you were to take advantage of that last 1/4" by grinding down the middle "ring" and remove the hood insulation you could even make a 455 fit... Maybe...