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Discussion Starter #1
85 bronco 351 windsor 650 holly carb
emissions vaccum lines gone and vaccum lines pluged

when i start it the whole truck shakes and the idle is real choppy
and dies everytime i stop
when i go down the road, its as smooth as can be

ive changed plugs wires and had timing set and no improvements

help needed any ideas thanks:whiteflag
 

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Did you install the carb? Did you adjust it? Did you set the timing with the vacuum advance unplugged? Does it ping or skip/miss under a load? How many miles is on the vehicle? Provide more detailed info, plz.
 

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Did you install the carb? Did you adjust it? Did you set the timing with the vacuum advance unplugged? Does it ping or skip/miss under a load? How many miles is on the vehicle? Provide more detailed info, plz.
no allready on
adjusted by a friend
yes advance was unpluged(was done by a mechanic (dads friend))
nope can run wide open and not a mis in the world
alot idk 150000 it rolled over

any more info that i can provide i shall if i can just asked
 

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some of the vacuum lines you plugged off may need to be open to get the right air/fuel mix yes you dont need them for smog but it was a metered vacuum leak that was part of the system if you didnt tune the low end carb to make up for this it my not be gitting enough fuel or even to much id try to run some of the line to a t or something like unplug one or 2 to try and get something to turn up
 

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Discussion Starter #6
well i think its running lean because sometimes if i floor it from a stop it backfires out the carb for a sec then goues
also it runs good with the choke on but as soon as it turns off it wont idle

and for the compression test i have not done this
i know the compression is low because i can spin the balencer by hand
also 2 cynlinders were oil soaked but the truck dont smog it just has blowby
 

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One thing to quickly check is to see if the bushings in the distributor are worn. Take the rotor off and check for play in the shaft. If it wobbles, that'll cause a rough idle.
Not saying that's it, but worth checking.
 

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Assuming that your ignition is up to spec.....my guess is that you gots a busted power valve in conjunction with a weak, leaky or out-of-adjustment accelerator pump. And you might want to check your float levels while you got the carb off for repairs.
Just for the record, there is a specific float setting for each Holley List number....and contrary to popular opinion, it usualy doesn't coincide with where the "sight plugs" are located in the bowls. Carb kits come with the gauge you need.....and instructions.
Also be aware that it aint uncommon for used Holleys to be out of whack due to things like jets, power valves, squirters, pump cams, float settings etc being swaped (or modified) in the past.

Or it could be something as simple as a bad base gasket or adaptor plate.

Hope something here helps.

DGW
 

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Vacuum leak,Torque the carb down ,torque the intake,and reset your carb to out of box specs and start from there.
Is the temp runnin a little higher at times but crazy hot?

nope can run wide open and not a mis in the world

well i think its running lean because sometimes if i floor it from a stop it backfires out the carb for a sec then goues
 

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You are running lean, I would start by checking the carb to intake gasket for leaks. It has been mentioned to set your carb back to factory settings, this is a good idea, it gets it kinda close. you misht want to recheck your vacuum plugs for cracks/pinholes. definatly check your float level. you will also want to check if your distribuitor is hooked to constant vacuum or ported vacuum.
 
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