ok, the stang has been sitting for awhile and its time i get her going.

couple things i took care right off the bat....
i had a plug wire suspected of grounding out to the header - fixed
plugs were very fouled out - apparently it was VERY rich - new motorcraft cheapy plugs
timing was out of whack from screwing with the dizzy TRYING to get it right - fixed, i think... set to about 10 with the adv. unhooked.

i turned all air fuel screws back in to the bottom and came out 1 turn on each, it seems like its better but still i think its loading up because it'll run semi-good for a minute or so and then starts stumbling which ends in it falling on its face. seems like the mix screws shouldnt be going in any further than 1 turn should they? the jets shouldnt have any effect on idle quality from what i understand, so wtf gives?

fyi i never really had a chance to dial in the speed demon, so i'm flying by the seat of my pants right now - but the floats are set.

also, if i hook the dizzy vac. to full vac source from the carb it dies. if i hook it to the timed vac source from the carb it still runs half like crap - like its not getting enough timing or something. basically runs like a dog. the only thing i can think of at this point is maybe theres a stuck weight in the dizzy or a spring popped off or something?!?! just for reference its a duraspark style with a msd 6al so theres no points to deal with [8D]

any thoughts????

 

It sounds like 1. You have too much timing advance and 2. Too little fuel.

I think a good starting point for timing is 6* BTDC. You were correct to disconnect the vacuum before you set the timing. Did you also plug the ports?

On my Edlebrock, they say to screw the adjustment screws all the way in and then back out two turns. While watching a vacuum gauge, screw in one adjustment screw 1/2 a turn at a time only until you see a drop in vacuum. Then move to the other adjustment screw.

I don't know anything about Speed Demon carbs, but here is a link to a website where you can download a manual. That will probably help.

http://www.barrygrant.com/demon/default.aspx?page=10

Good luck!

 

get a vaccum guage on it and go from there and i would first set your idle screws at stock pos then get the vaccum guage out and move the dist (with vac line not attached) until it reads the highest on the guage. after that it shold run mighty good thats what i do and i pass emissions with flying colors and i got plenty of power and i loked at my plugs and they are hunky dory

 

yeah i dunno about the lean thing, i mean the old plugs were black as hell.

i have a vacuum gauge, but to be perfect honest i have never put it to use . i'll have to fug with it i guess. i was having a hell of a time setting the timing too, i had it down to about 850-900 rpms which was as low as i could get it without it wanting to die and the damn thing was still jumping around. i couldnt seem to get it to flash on same spot consistantly. i would say about 4-6 degrees worth of hopping around.... and this is with a gear drive so WTF?

btw that damn gear drive is louder than i wanted it to be and i swore i ordered the "quiet" one. im thinking about ripping it out and selling it to get a good chain instead. anyone wanna buy a barely used gear drive for like 100 bucks?

 

Like I said, I have an Edlebrock, so Speed Demon carbs may only be one turn out from bottom to a lean best idle starting point. I really don't know. What does the manual say?

Were you using the distributor to set your idle speed? The timing and idle setting are adjusted by different things. There should be a screw on the carb for the idle. I'm sure that will also be in the manual.

Good luck!

 

actually i have a BG tuning DVD that came with the carb but it was so rediculously boring i couldnt stand to watch it for more than 5 minutes. seriously, worst tuning dvd ever made by anyone ever - based completely off the lameness factor.

no i wasnt setting idle by timing - im fairly good with this sorta thing and thats why its driving me nuts.

 

The idle mixture screws should be set to maximize vacuum, which will also give you the highest idle speed. You'll have to continually adjust the idle speed to get it right. I generally set my idle down to about 600 rpm (barely running with my engines usually), and tune there. Then, set the idle back to 1k, and recheck everything. Jet size (your rich problem) should not affect idle quality if the carb throttle blades are set correctly.

I set the initial timing at true idle, to eliminate any change due to the mechanical weights.

 

ive been having a hard time with that because it doesnt wanna run worth a crap lower than the 900 ish range (it NEVER liked to idle real low, but lower than that for sure.

 

Throw that POS carburetor away and get you a 4100.The reason those plugs are so black is that you are running way too rich, as you are aware. Adjust the one you have to run leaner, or get another carb.

 

ya i know i need to lean out in a big way, it just seemed like 1 turn out should still BE lean. does it matter if you happy place falls at some rediculous setting like 1/2 turn out or something?

with a rear metering block and vacuum secondaries how does that come into play cause the back two shouldnt be feeding anything to the motor at idle anyways right? wtf is going on here LOL

and even more worrying than that - wtf is up with my timing its driving me nuts