ignition timing and carb adjustments

[63130dp]

being not the greatest carb or timing guy I decided to rebuild my carb and screw up my timing after failing an emissions test.

seems i had to much unuses fuel to pass the test. which makes sense since the bronco ran rough/used a ton of fuel and backfired alot.
What the mechanic told me was "I had a broken carb with worn bushings" I laughed and took off.. bought a rebuild kit and started on it.

The carb was clean by motorcycle standards but replaced everything anyway.. so here are the questions. How do I set my carb when I have some sort of electric ignition on it?? I dont know what kind it is exactly but have some picts I can send.. also how do i set the timing on the ignition.. the mechanic said it was set really far advanced to keep up with the amount of fuel the carb was dumping in...

I like to do things myself but for time reasons i had to take it to a mechanic(bad idea and i'm out 80 bucks).. well now it looks like i will be doing it myself so any help would be great.
thanks in advance.
http://webliberations.com/ignition.jpg

 

[kwspony]

tIMING AND CARB

Not sure what year your bronco is but, on my 68 it is 6 degrees. remove and plug vacuum lines at the distributor and set your timing. As for your carb, if the bushings are wore out rebuilding it won't solve all your problems as you will have a vacuum leak at the bushings. You should take it to a carb shop and have them replace the bushings. It looks like you have a Pertronics ignition module. Once you set the gap on it you shouldn't need to worry about it. If you have any more question, just ask.

 

[broncnaz]

Ditto that set timing downaround 6 degrees as for the carb once timing is set turn mixture screws until you get the smoothest idle you can then make sure your choke is open all the way just make sure the engine is at operating temps first before you do any of this. your carb bushing maybe worn but that would tend to lean it out not richen it. you may also want to put in new plugs and air cleaner before the next test every little bit helps

 

[catomakt]

The pertronics ignition module should be set at .030 from the cam on the distributor. Just in case you didnt know.

 

[63130dp]

cool thanks for all the help. I will give it a shot. its a 71 by the way.

 

[vbro]

I got my rig to pass smog not too long ago. I have a 450cfm 4v carb and stock cam. Specs for timing is also 6 btc. What I did to pass was set my idle to where it ran the smoothest. Once everything was running good I set my timing at 0 tdc and curb idle at 1500rpm. DMV limits curb idle to 2500rpm . Went to the emissions center and passed.;D

 

[kwspony]

71?

where do you live? I thought california's smog laws suck, at least we don't have to smog anything 73 and older. at least i think it's 73.

 

[63130dp]

1971 is the limit.
damn
i would like a 1970 glove box.. anyone got one.

 

[Rustytruck]

Ok since you want to pass smog you will have to set your timing at proper idle speed to 6 degrees BTDC with the vacuum hose plugged and disconnceted from the vacuum advance make sure thes is no leak in the diaphram while your at it. After you have rebuilt the carb and replaced the powervalve which is probably bad by your descriptions set the needle screws 3 turns out. they must be adjusted the same amount. Hook up a vacuum guage to manifold vacuum and start the truck. let the truck warm up some if you can. if you have a tachometer adjust the Idle speed to 750 rpm and looking at the vacuum guage you need a very steady needle as high a vacuum reading as you can get. At first adjust the idle mixture screws in quarter turn increments (adjust both screws the same amount.)Either in or out it doesnt matter if the vacuum reading raises you are going the right way if it doesnt rais or drops you are going the wrong way go the oppsite direction. Stop at the highest reading on the vacuum guage. You want this as precise as you can get so start with quarter turns and then 1/8th turns then 1/16th of a turn. you need the highest steady vacuum reading you can get. Now your carb is set. If you cannot get an extermely stable vacuum reading you have other problems that need attending to. Make sure that you have no vacuum leaks and the distributer vacuum hooked to the venturi vacuum on the front of the carb. timing set properly, Idle set at 750 rpm and the vacuum at the higest smooth reading. If you have all of this done you should easily pass smog.