1984 Chevy 350 still being a headache to get running right

[grandall1972]

As the vacuum is low and it's running badly above idle you might have an issue with the vacuum advance - a bad advance diaphragm or a leak in the hose to the distributor.

Good point. Would that effect off idle timing? As currently set the timing goes from 12 degrees at idle to 36 degrees at 2500rpm pretty smoothly.

 

[MuleShoe]

When warms up spay WD 40 around edge of intake where it joins heads to see if there is any air leak ! Can also spray around where carb bolts to intake ! Been close to 30 years since my mechanic days!

 

[davans]

https://jandlautoservice.com/
Give Gabe Parker a call at J & L.
Check out the gallery photos on the web-site.
I worked here for years in the late 80’s into the 90’s
Same family owns it. Great folks.

 

[Kyzrsoze]

Good point. Would that effect off idle timing? As currently set the timing goes from 12 degrees at idle to 36 degrees at 2500rpm pretty smoothly.

If you seeing it advance smoothly, it's likely not the issue. If it's a vacuum issue you should see it at idle or in the timing advance. Since you aren't I'm guessing its either starving for fuel or running rich when you give it throttle.

Is the carb new or rebuilt? Aftermarket or QJet?

 

[41mag]

If you seeing it advance smoothly, it's likely not the issue. If it's a vacuum issue you should see it at idle or in the timing advance. Since you aren't I'm guessing its either starving for fuel or running rich when you give it throttle.

Is the carb new or rebuilt? Aftermarket or QJet?

Looked like a Carter AFB(edelbrock tag) according to pics....they are simple.

 

[Toothlesswun]

What rpm does it idle at?

 

[bambam]

"Revs while parked well"

How about when you stomp the %#*% out of it and hold it WIDE open. If it revs good--like the motor will blow up if you stay at it-- then look for something else- rear end locking up?, trans?, brakes?, wheel bearing?, etc.

 

[whiskerz]

A few random questions. Is the fuel tank vented. ? go drive it with the gas cap off and see if it runs better. Also look at the new fuel lines and make sure there are no kinks or squished lines. Follow it all the way to the tank. You could have high fuel pressure due to a restriction. Is it smoking ? color ? how do the plugs look ? what color ? gapped in specs and right heat range ?

 

[grandall1972]

If you seeing it advance smoothly, it's likely not the issue. If it's a vacuum issue you should see it at idle or in the timing advance. Since you aren't I'm guessing its either starving for fuel or running rich when you give it throttle.

Is the carb new or rebuilt? Aftermarket or QJet?

carb is an edlebrock 600cfm.

 

[grandall1972]

What rpm does it idle at?

750rpms