NOS BIG BLOCK AIR CLEANER

[67 Nova Boy]

X2!

Dave
67 Nova Boy

[67 Nova Boy]

This is from 1996 or so from this site on this issue of Open air cleaners.

Dave
67 Nova Boy

THE 1970 L34 L78 AND LS6 6485239 OPEN ELEMENT AIR CLEANER ASSEMBLY USED ON 1970 SS 396 CAMARO’S – SS 396 NOVA’S AND SS 396 454 CHEVELLE’S USED THE SAME BASE AS THE 1967-69 6423907 AIR CLEANER ASSEMBLY BUT WITH A DIFFERENT VENT TUBE THAN THE 6423907 AIR CLEANER ASSEMBLY - THE 6485257 IS THE BB DUAL SNORKEL AIR CLEANER ASSEMBLY

WHEN THE 1967-69 6423907 AND 1970 6485239 BASES ARE PLACED SIDE BY SIDE IT IS EASY TO SEE THAT THEY ARE IDENTICAL BASES EXCEPT OF COURSE FOR THE VENT TUBES

BOTH BASES HAVE THE EXACT SAME STAMP MARKINGS AND INDENTATIONS ALL IN THE SAME EXACT LOCATIONS - EACH BASE HAS 3 DIFFERENT POSSIBLE VENT TUBE PADS IN THE SAME LOCATIONS - THE LOCATION WHERE THE VENT TUBE IS LOCATED IS THE SAME ON BOTH BASES - THE EXACT SAME INDENTATIONS FOR CLEARANCE ON THE CARB BOWL AND FLOAT ADJUSTING SCREWS ARE ON BOTH BASES - THE ALINGMENT TABS FOR AIR CLEANER TO CARB ARE THE SAME ON EACH BASE - THE TWO BASES ARE IDENTICAL

BOTH AIR CLEANER BASES HAVE A DEPTH MEASUREMENT OF 2” FROM WHERE THE AIR CLEANER SETS ON TOP OF THE CARBURETOR TO THE BOTTOM LIP OF THE AIR CLEANER BASE, WHICH MEANS BOTH AIR CLEANER BASES WILL RIDE AT THE SAME HEIGHT

THE HEIGHT OF THE INTAKE MANIFOLD EITHER A HI PROFILE OR LOW PROFILE INTAKE MANIFOLD HAS NOTHING TO DO WITH THE RIDE HEIGHT OF THE AIR CLEANER BASE

ALL AIR CLEANER BASES MUST CLEAR THE FRONT AND REAR HOLLEY CARB BOWLS AND ANY MOVING PARTS ON THE CARBURETOR – THE CARBURETOR SETS THE RIDE HEIGHT FOR ALL AIR CLEANERS NOT THE INTAKE MANIFOLDS

THE VENT TUBE USED ON THE 1970 6485239 AIR CLEANER COMES OUT STRAIGHT AT THE BASE FOR 1½” AND THEN BENDS AT A 90 DEGREE ANGLE AND ENTENDS STRAIGHT OUT PASS THE LOWER LIP OF THE BASE 1”

THE VENT TUBE ON THE 907 BEGINS TO ANGLE AT ABOUT ¾” OR SO WITH A 45 DEGREE ANGLE AIMING DOWN TOWARDS THE INTAKE MANIFOLD BUT STOPS AT THE OUTER LIP OF THE BASE

THE VENT TUBE IS THE REASON FOR THE PART NUMBER CHANGE FROM 6423907 TO THE 6485239 AIR CLEANER USED IN 1970 WITH THE ONLY DIFFERENCE BEING THE SPECAIL VENT TUBE

THE HEIGHT OF THE INTAKE MANIFOLD DOES HAVE AN IMPACT ON THE VENT TUBE HOWEVER - THIS IS WHY FOR 1970 THE 396 454 LOW RISE 3963569 INTAKE MANFOLD REQIURED A LONGER VENT TUBE WITH MORE ANGLE COMPARED TO THE VENT TUBE USED WITH THE
67-69 396-427 HI RISE INTAKE MANIFOLDS

THE 1970 6485239 AIR CLEANER ASSEMBLY LISTED IN THE FOLLOWING ASSEMBLY MANUALS SHOWS A PERFECT DRAWING OF THE VENT TUBE USED WITH THIS AIR CLEANER ASSEMBLY:

CAMARO ASSEMBLY MANUAL – UPC L34 SHEET A7
NOVA ASSEMBLY MANUALS – UPC L34 SHEET A6
CHEVELLE ASSEMBLY MANUAL - L34 SHEET A7 L78 SHEET A8

HOPE THIS CLEARS UP THE MISCONCEPTION ABOUT THE 1970 6485239 AIR CLEANER ASSEMBLY

[66 Biscayne]

How about one without the vent tube (never had one)....and a painted lid (never had chrome plating), and the lid has the silk screening on the underside. Picked up at a swap meet manny years ago.....Any opinions on the application ?