Holley 4 BBL

  • Thread starter Thread starter Anonymous
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Anonymous

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Okay, I want to disable the secondaries on my 4 bbl. Step by step. How do I do it?..ZZ
 
The carb's running fine. I'm just considering saving money on gas, until I put a 2 bbl. on my 390. I love the power it has, but MAN is it taking a chunk out of my wallet. You see I'm using it until I finish my 200 I6 rebuild and I drive 66 miles one way to work..ZZ
 
Are they vacuum secondaries? You could get a quick change kit for the secondary spring and put the BLACK spring in. I dont think I EVER got the secondaries open with that in there.

Ron
 
Isn't there linkage that can easily disable the secondaries? I see a short piece of linkage on the same side a the main throttle connection, I was wondering if there is another spot to look at..ZZ
 
is this a holley 4v carb?... Is it a vacume sec. carb? ... If yes to both then there is a verticle piece of linkage on the non linkage side directly above the throttleshaft. You will have to pull the e-clip off of it and slide the rod off the lever. that is it.
you may not save as much as you think though. good luck with your milage.
Jim
 
If he does that he also needs to wire the secondaries shut? Otherwise they may suck wide open and not close giving a full throttle experience.

Ron
 
I hear what your saying but I just went out and checked mine and I can't see a return spring. Are you saying to add one?

Ron
 
A strong spring added only to the secondary linkage won't prevent it from opening, but your foot will tell you exactly when your "mileage" point has been reached.
Try to attach it so the spring is tensioned at 90 degrees to the linkage arm movement.
 
What engine and carb have you got. Got any comparison figures on the economy loss. Ive heard 4 bbls are not as economical but Im not sure why, other than because of the plenum volume or because of hard acceleration. But since your cruising I dont really understand it. Anyone care to comment ?
 
Another suggestion: Change carbs out to a spreadbore. I ran a Holley List #3310 on my Pontiac 400 for a couple years. I measured the milage and got around 13 mgp with the top down, doing about 75 mph on the Michigan Autobahn. Changed to a Quadrajet and the milage picked up to almost 16 mpg doing the same trip :D . So you get the best of both worlds, 2-V economy with a couple small venturii but big ol' honkin' secondaries when the need arises :twisted:

You might be able to find a spreadbore on Evil-Bay or just by looking around. I know Holley makes/sells a spreadbore carb too. I don't know if its a direct swap, you'll have to research it :wink: .
 
you can find Q jets on ebay all the time for $10 - $50 . A spreadbore will not bolt up with out an adapter .
 
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