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| | | | Joined: Jan 2007 Posts: 202 Wrench Fetcher | | Wrench Fetcher Joined: Jan 2007 Posts: 202 | Will a 2" spacer do better over a 1"? Better atomization? This is for a modest Edelbrock 4bbl carb. I need to order one tomorrow and wanted to know which one would be the best for mpgs. Thanks. Henry | | | | | Joined: Feb 2000 Posts: 5,206 'Bolter | | 'Bolter Joined: Feb 2000 Posts: 5,206 | A lot depends on the carburetor, intake manifold, and even camshaft profile. The spacers can have four holes, two holes, or open. Now do you want plastic, wood, or metal?
What design is your intake? dual plane? single plane?
V8? inline 6?
I really doubt you will see any fuel mileage increase unless something is really wrong to start with.
Joe
| | | | | Joined: Jan 2007 Posts: 202 Wrench Fetcher | | Wrench Fetcher Joined: Jan 2007 Posts: 202 | My engine is a 350 with a mild truck cam. It has the older style quadrajet manifold for it. Was going to use a single plane adapter. I curently have an Edelbrock 600 cfm carb for it model 1406 non emission. I have posted many times in reguards to inlines. Had a 292 in there but 8 mpg on a brand new motor was hard to deal with. So it was back to a V8 which does better. Still love the ole inlines though. Anyhow just curious if the 2" would help any or just use a one inch. Thanks JoeH | | | | | Joined: Feb 2000 Posts: 5,206 'Bolter | | 'Bolter Joined: Feb 2000 Posts: 5,206 | Henry, sorry it took awhile to get back to you. You should be looking for a Quadrajet to run instead of the 600. Try and find a late 70's early 80's with out electronics. The primary's will be smaller then the 600's so fuel mileage and drivers feel will be better, but if you need power the secondaries are much bigger. You spacer should match the intake, one big hole for open manifold, two hole for aftermarket dual plane, and four hole for hole intake. All you can do is try one for awhile and see what it does. Joe
Last edited by Joe H; 09/02/2008 3:53 PM.
| | | | | Joined: Feb 2006 Posts: 150 Shop Shark | | Shop Shark Joined: Feb 2006 Posts: 150 | Henry, My vote is for a 1 inch spacer vs a 2 inch. I put a 2 incher on my edelbrock intake and edelbrock 1406 carb, it really throughs the geometry of the linkages off. I used a pholic (spelling??) material as thats what Edelbrock recommends.
HOWEVER, I think you post is relative to bolting a Edelbrock 1406 carb to an GM Q-jet intake. My 2 cents, don't. Either follow Joes excellent advice about getting an Q-jet carb or get an dual plane intake compatible with your 1406 AND get a 1 inch pholic spacer.
I believe GM used a thick gasket (about 1/4") between the intake and Q-jet carb. I wouldn't suggest additional spacing with the Q-jet setup. Good luck. | | |
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