any carb guys here?

[Monster Mike]

so ive got timing issues with my 302, that thread has been posted just hours ago if you want to read up on that as well.

im running real rich with the 2100 auto lite. ive got 4:10's with 35's and im getting 6.6mpg in town. i know i have to factor in the larger tires so maybe im really getting 7.5mpg but i still think the carb could get a tune up.

i pulled the #1 spark plug 2 days ago (when i saw how crappy my mpg was) and it looked fine, last night after messing with the timing and idle mixture screws and then driving less than 2 miles the same spark plug is black.

i then pulled the hat off the carb to see what jet sizes im running which are #48's is that a big jet for my application?

Heres what im curious about, my 302 has a hesitation under load when i take off at a green light or give it some gas while already going. other than that it behaves fine. no back firing no dieseling sounds good at high rpms and idles smoothly. could my power valve cause excessive fuel to poor into the manifold?

my idle mixture screws are at 1.5 turns out right now but it seems to run better at.5 to .75 turns out.

could a bad carb thats dumping excessive fuel into the motor cause the motor to not run unless the timing is excessively advanced?

if i adjust the timing any less than 22 degrees advanced it wont start or run well however at 3,000 rpm w/o the vaccum advance hooked up to the dizzy im only running at 34 degrees advanced

I double checked my timimg and the #1 piston is lined up with #1 mark on the dizzy and is at tdc on the compression stroke

 

[jperry1290]

vacuum leak? i had similar issues and found that my vac advance was bad

 

[Monster Mike]

No vac leaks around the carb, man, or heads. You think the vac advance is leaking inside the dizzy?

 

[jperry1290]

yeah thats where mine was leaking from and it threw me for a loop. I replaced all the vac hoses, rebuilt the 2bbl, then added new intake and 4bbl carb (got for free) and it still bogged under load when put in gear. Vac adv seemed to fix the prob.

 

[bronco_daddy]

I am running a Holley SA 470 and I had a bog right at idle take off and a bit rich at idle also whereas you would smell the fuel out the exhaust.

I pulled the power valve and it was an 8.0. I have a good size cam in it and the proper way is to pull vacuum and get your number that way but I had already figured where it needed to be. Dropped a 4.5 in it, readjusted the floats as they were way low and VIOLA'...truck snaps at idle, fuel smell is gone