I have been trying to dial in my carburetor for my new engine, but my engine runs extremely rich no matter what. I have my edelbrock leaned way out and my plugs still show very black, and it smokes black out the exhaust when I punch it. I just put in the leanest primary jet/rod combo in my carb, and the engine seems to load up when it idles in gear for a bit, you can smell the raw fuel it's burning. the engine doesn't perform as well as it should either, although it runs pretty good, it is still lacking power.

it almost seems like the chart in the edelbrock manual is backwards and instead of leaning out the carb, im actually richening it?

any thoughts on what is causing this lean condition? the air filter is new, my ignition components are all new with less than 5000miles on them. most of it is accel though.

I'm stumped

 

What size rods and jets do you have in the carb now?

 

.107 main jets
068 X 047 rods
.104 secondary jets
vacum is steady, slightly lower reading than normal cause of my cam (can't remember exact hg)
I have my idle mix set at the "lean best" mix
my accelerator pump is set at the top hole (least stroke) and I'm running orange step up springs.

 

Oh my that is set up rich.

Are you running a race cam or something? 500CI?

I'd try more like .098 or .100 front and .096 rear. Maybe even smaller in the back like .092. Leave the rods alone if possible, those are fairly decent, or the 7047 rods would work good too.

 

what size carb is it?

 

according to the carb manual, thats the leanest setting possible on my 1407 700 cfm carb.
I just recently went with that combo. it still runs rich, plugs are DARK brown, smells gasy when running (no detectable leaks) and hauls out black when i step on it.
I do however get a lean spot miss at off idle, so my carb is definatly messed up.

I have a stock replacement mech fuel pump, is it possible that it can be putting out too much pressure? I've had it for 2-3 years.

what else could be causing this!?

 

Do you get idle speed adjsutment via the bleeder screws? If not, or very little, then you may have the float too high, if it's an older carb, could be the float seat is not sealing well.

I had a 1407 once, though it was a 750?

 

the carb is a little over a year old, and yes it's a 750cfm
the floats are adjusted to 7/16 so it wouldnt stall on hard breaking (as per the manual) Idle adjusts fine though, but I will check on the float level idea, maybe drop it down for now to see if that helps.

any other ideas?

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WHO NEEDS VTECH? I HAVE VORTEC

1982 Camaro "VortecZ"
Vortec headed 350 bored .02 over, comp xtreme cam, edelbrock 750 carb, edelbrock performer rpm intake, dynomax 1 5/8" shortie headers, accel ignition, stock TH700r4, powertrax locker, 3.73's

 

You should check the pressure, make sure its around 5psi.

I still think its set up too rich.