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Edelbrock carb questions

Kain

Kain

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took carb apart and found aluminum shavings and grass in the darn bowls and where my finger is pointing in pic below. also had old gasket material in it.

My question is how come it will surge really badly unless i clamp off vacuum to distributor?

what am i missing? I know more about holley than eddys

IMG_20190221_155627.jpg

IMG_20190221_180112.jpg
 
Not sure about debris in bowl? Hard to see looks like top of carb is off.
Surge may be due to lean idle. Is your vacuum advance leaking? Maybe fatten up the jetting. Get the tunnel kit with rods and jets. Then have at it not difficult process.
 
carb top was off to clean inside and see why would not idle right
I found debris in it and have idle screws out 1 3/4 turns
i will test vacuum advance tomorrow Wind is blowing and it got cold
 
hmm I see the diagram showing full vacuum to dist adv, but it goes against my understanding of rpm and spark timing needs. thou with lower throttle angle in overdrive at cruise, manifold vacuum would see more advance. So my question what would timing advance look like at wide open throttle when manifold vacuum is near 0 and your rpm is over 3k. The time to start and burn the air fuel in the cylinder is still the same as at idle. So how does this work ? Does this set up rely on the mechanical advance at high rpm ?
 
Generally mechanical advance handles timing under load, and vacuum is for part throttle.

Obviously there is overlap between when the manifold and vacuum are adding timing, and that all comes down to the springs, weights and RPM on the mechanical side, and from vacuum advance adjustment (vacuum rating of the can, limit the vac advance can pull, etc) on that side.

"Timed" or "ported" advance is for emissions, nothing more. The engines run better at idle with more timing than GM was able to run, but that was all a result of carbureted emissions strategy coupled with the technology available at the time. As vacuum drops to near nothing under heavy throttle, ported or timed is meaningless under *that* condition.

Injected engines run quite well at idle (among other reasons) because they typically run 20*+ of advance at idle. It's hard to achieve that with mechanical/vacuum advance, and still have it start without the starter fighting ignition.
 
Well I'm game to give it a shot. Base timing is set w/o vacuum?then apply vacuum and set idle rpm. So mild cam 350 Qjet single 3" exhaust base timing 8-10?
 
ok this carb acts really weird , if i lock out timing and set at 35-38 deg it will start and run
set base at 16 like it was before it wont try to start
switched ports and loping got worse until clamped off vacuum to that port
tested vacuum can with vacuum gauge and it holds vacuum
 
I set my timing with a vacuum gauge. It gets me closer since I can’t trust my timing marks in the balancer. The tab is way off. Verify your timing tab matches number ones too dead center so you can verify “0” is set correctly from the tab. Base timing is usually 4-8 degrees to run then connect the vacuum to the dizzy. Then set the idle speed. Base setting on my edelbrock I believe was all the way in then out 2.5 turns. I use the right side port on my carb for timing. It depends on your setup of course but mine ran better there. It could be your distributor weights are off and not advancing or are stuck open and always advancing. I’d open it up and look just to be sure they are moving correctly.
 
Edelbrock has some good tech videos that i’ve Used back in the day.

https://www.edelbrock.com/edelbrock-installation-and-tech-videos


With rubber & metal in the bowl I suspect some blockage.

Check to make sure your vacuum & fuel lines are in good shape and you have a good clean filter and no vacuum leaks.

Do you know your fuel pressure? Maybe the pump is getting lazy. I think they need around 7psi to run good.

Maybe take the carb off and remove the air/fuel mixture screws and blow some air thru the ports.

Make sure your floats still float.

Trying to adjust timing and carb at the same time is a pain.

I would set the timing where it was or somewhere between 8-10 BTDC you can usually feel the money spot if you’ve done it enough, and then focus on the carb.
 
well i learned the reason the eddy carb ran funny is the intake gasket blew again
drained the oil and was chocolate milk started looking and found the intake is leaking passenger side front nd rear
i have an edelbrock torker 2 intake i am pulling the summit off
 
So I have to ask, did you use sealer around the coolant ports? And did you go back and retorque the bolts after the first heat cycle and then again later down the road? I have even found that lots of manifold manufacturers say to use sealer around all of the ports. I am not sure about this. The gasket manufacturers say that their stuff seals.
Or do you think that there is a bigger problem? Something warped?
 
i did but summit intakes runners are off, probably cause there made in china
when i pull it tomorrow ll take pics next to the gasket and show you guys what im talkin about
 
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