Carb Question

URDONE4

URDONE4

Club Member
I have a 509 Merlin Bottom End with Edelbrock RPM Heads and A Performer RPM intake with a 870 Holley Street Avenger Carb sitting on top. When I am driving the truck it feels like the second set of barrels wont open and when I look at the carb sitting and revving, the second set of barrels isnt opening. I was wondering if anyone knew how to rectify this problem or if the secondary just went bad. When the truck runs right there is a HUGE difference, the motor made over 550 at the crank but it feels well under powered when it is not running right....
 
no it is not vacuum secondary...i was checking the floats today and noticed that the primary float sight is broken, i know that is not causing the problem with the secondaries but its just something more I have to fix now...
 
Are you sure its a street avenger carb? Seeing how the vacuum secondaries are one of the primary components that make it a "street avenger" carb. If you have modified it and made it a mechanical secondary style carb, the linkage could be installed incorrectly, or not connected at all. Also, make sure the correct secondary cam installed as well.

Can you get a P/N off the carb to be sure exactly what you have?


Features
No Trouble Quick Change Adjustable Vacuum Secondary
4th Generation No Trouble Power Valve
Built-In No Trouble Secondary Fuel Filters
Adjustable Needle and Seat
No Trouble Electric Choke
Four Vacuum Ports
Street Avenger Fuel Metering System

medium%20SA%20intro.jpg
 
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If its mechanical secondary. Check, that the throttle cable is adjusted properly, Check the linkage from the throttle arm to the secondary shaft. I'd pull the carb off the vehicle and work the linkage by hand from closed to WOT and see it the seconary plates open then.
 
QuickLX said:
Are you sure its a street avenger carb? Seeing how the vacuum secondaries are one of the primary components that make it a "street avenger" carb. If you have modified it and made it a mechanical secondary style carb, the linkage could be installed incorrectly, or not connected at all. Also, make sure the correct secondary cam installed as well.

Can you get a P/N off the carb to be sure exactly what you have?


Features
No Trouble Quick Change Adjustable Vacuum Secondary
4th Generation No Trouble Power Valve
Built-In No Trouble Secondary Fuel Filters
Adjustable Needle and Seat
No Trouble Electric Choke
Four Vacuum Ports
Street Avenger Fuel Metering System

medium%20SA%20intro.jpg
Click to expand...


i stand corrected sir, i was thinking about my windsor carb when i responded, it is indeed a vacuum secondary, sorry...
 
i already have the yellow spring in it and it still isnt working properly, any other suggestions
 
This isnt rocket science...no vacuum in the can, spring opens plate!
Change secondary's spring for rate of opening!
Check diaphram for leaks, cuts slits, seal rot.
Check for binding linkage...

My Questions I have are:
What manifold do you have it on??? Performer you said??? They compatable??
Have you tried to push them open with or without engine running???
Are secondaries carboned up under the plate???

Some of these carbs wont work on some manifolds because there is no clearance in the manifold for the secondary thottle plates to open. Also they are notrious for carbon build up under the plate from lack of secondary opening or backfires. The ole 3310 750 LT1 carb was the worst.

GL...

~Cheese~
 
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