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Old 05-21-2008, 08:37 PM   #26
Pyrotechnic
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Re: Carburetor Selection

I've seen them come from the factory jammed up and bent. There's really nothing to guide to the rod down in the jet, which is OK, because once you have the cover plate on, the rod can't move out of the jet. During assembly however, if you don't verify that the piston and rod move up and down freely, it's really easy to jam the rod to the side of the jet then torque the cover down.

If they were getting stuck, make sure there are no burrs in the piston bores and make sure the top plate gasket isn't misaligned and riding on the side of the rods and creating resistance.
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Old 05-22-2008, 05:57 AM   #27
Ivan D.
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Re: Carburetor Selection

Pyro, the pistons always move freely when I installed them, I made damn sure of that. There was absolutely nothing down the bores that could possibly jam them, yet they always managed to get stuck after a longer drive - I was at a total loss on that one, never seen or heard of anything like that. Truck's gone now, traded it two months ago for the diesel I drive now, but I'm still stumped at what could have been possibly wrong with that otherwise brand new carb...
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Old 05-23-2008, 05:02 AM   #28
LEEVON
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Re: Carburetor Selection

Quote:
Originally Posted by ocbaud View Post
i had the 650cfm avs carb in my truck when i built the engine. could never ever get it running great. finally upgraded to a 650 speeddemon and will never buy another carb again. i dont know why people complain about how hard they are to tune, it's way easier to adjust than the edelbrock i had.

that being said, if you're looking at the avs carbs, they are in the same price range as the demons
Second that ocbaud.

Vern350, in case you haven't bought a carb yet, I think the Demon 650 w/ vacuum secondary would be a great choice. I used to be scared to death of carb tuning, mainly because I didn't have good luck with Edelbrock Performers. After I figured out how to tune the Demon, I'll never go back.
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Old 05-25-2008, 12:19 AM   #29
Pyrotechnic
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Re: Carburetor Selection

Quote:
Originally Posted by Ivan D. View Post
Pyro, the pistons always move freely when I installed them, I made damn sure of that. There was absolutely nothing down the bores that could possibly jam them, yet they always managed to get stuck after a longer drive - I was at a total loss on that one, never seen or heard of anything like that. Truck's gone now, traded it two months ago for the diesel I drive now, but I'm still stumped at what could have been possibly wrong with that otherwise brand new carb...
I think I'm having a similar issue to what you were experiencing. I've been playing with the AVS a little bit, and sometimes when I gun it, around 4000 RPM it starts feeling short on power and revving slower. Other times it rev's to 5000 RPM quickly.

When I was reassembling the carb, I noticed one of the metering rods...the one that was jammed from the factory, took a little wiggling to get it to slide down and move freely. The other side in comparison was like butter, it just dropped on and felt smooth.

I'm gonna try and get to the bottom of this issue. I hope there really is something wrong or I'll be chasing a ghost.
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