Vacuum problem
Thread Starter
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Joined: Apr 2006
Posts: 52
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From: Fairfield Connecticut
Vacuum problem
im installing a new engine into my car and with the new engine the carburetor sits so low to the intake that i can't get the vacuum valve to fit into the intake because it sits right under the carburetor. I would put a riser in between the carburetor to raise it up but im having clearance issues with the hood so my question is, has anyone using an edelbrock rpm air gap intake, a holley street avenger 770 cfm carburetor and a 1 1/2 in drop air cleaner experienced this problem with the vacuum valve? And have they gotten propper hood clearance if they put in a 1/2 in riser?
Thread Starter
Advanced
Joined: Apr 2006
Posts: 52
Likes: 0
From: Fairfield Connecticut
drilling and tapping a runner, is a possibility but the manifold is bolted to the block and i'd have nightmares about those filings getting everywhere. And im going to have to take alook for other vacuum ports on the manifold because all the ports off the carb are taken up by other stuff.
Race Director
Joined: Mar 2006
Posts: 14,112
Likes: 27
From: Florida
Pcv, brake booster, and dist should have their own port. Others can be tee'd together.
Just drilled a runner the other day.
Take carb off, stuff runners with rags past where you want to drill. Drill and tap. Vacuum all shavings with a smaller hose duct taped to vacuum. Pull rags out. If any shavings are left they will come out with the rag. Vacuum again and your done.
Just drilled a runner the other day.
Take carb off, stuff runners with rags past where you want to drill. Drill and tap. Vacuum all shavings with a smaller hose duct taped to vacuum. Pull rags out. If any shavings are left they will come out with the rag. Vacuum again and your done.
Melting Slicks
Joined: Mar 2006
Posts: 3,341
Likes: 7
From: Connecticut
They also make 90* threaded elbows that may give you the clearence you need
I cant imagine an Edelbrock intake and a Holley SA not having enough vacuum ports
I ran a performer and a Holley SA 670 with no problems.
The hood clearance is a whole different issue which should have been measured before any parts were purchased
I cant imagine an Edelbrock intake and a Holley SA not having enough vacuum ports
I ran a performer and a Holley SA 670 with no problems.
The hood clearance is a whole different issue which should have been measured before any parts were purchased
Melting Slicks
Joined: Aug 2003
Posts: 2,135
Likes: 2
From: Dayton Oh
Originally Posted by jiber
im installing a new engine into my car and with the new engine the carburetor sits so low to the intake that i can't get the vacuum valve to fit into the intake because it sits right under the carburetor. I would put a riser in between the carburetor to raise it up but im having clearance issues with the hood so my question is, has anyone using an edelbrock rpm air gap intake, a holley street avenger 770 cfm carburetor and a 1 1/2 in drop air cleaner experienced this problem with the vacuum valve? And have they gotten propper hood clearance if they put in a 1/2 in riser?
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Le Mans Master
Joined: Mar 2004
Posts: 7,423
Likes: 1,458
From: Little Rock AR
Could it be that Edelbrock put that threaded port right under where a Holly carb would go?!?! ....Maybe an Edelbrock carb would fit in there better? Ya think maybe it was designed that way on purpose? 
Do you sense my frustration in that comment? 
No legitimate reason at all to put that hole under a Holley carb bowl.
There is a low profile fitting that works there but I do not know where to get one. I ran into this before on a different car and the 1" spacer did the trick. Probably not the answer here.
I would try to get the low profile fitting or pull the intake for a drill and tap session.
-Mark.
Do you sense my frustration in that comment? No legitimate reason at all to put that hole under a Holley carb bowl.There is a low profile fitting that works there but I do not know where to get one. I ran into this before on a different car and the 1" spacer did the trick. Probably not the answer here.
I would try to get the low profile fitting or pull the intake for a drill and tap session.
-Mark.
Heel & Toe
Joined: Jul 2006
Posts: 17
Likes: 0
From: Texas
Try Mo-Speed...low-pro vaccum port...part #5183, I bought one from them $20, works great on my hi-rise intake with Holley 650 double pumper, gives you 3 hook-ups. Can't locate their number at the moment...you will have to call them to order one. Should be able to find them on the internet or do a search for other threads here.
Melting Slicks
Joined: Mar 2006
Posts: 3,341
Likes: 7
From: Connecticut
Originally Posted by ahoover
Edelbrock makes a shorty elbow to mount Holleys on their intakes. It might work or I've often combined the fitting with a thicker carb gasket.
Sorry to stray from the original topic but may I ask what you are using for a rear bumper?
Its got the '73 style exhaust tips which looks very nice with the non steel bumper
