350 Distributor seating problems

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squarebiz

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jeff
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c10
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350
I have crate 350, with edelbrock single plane manifold, and had passed smog the last 2 times, well i chg carb to edelbrock 1400, from quadrajet. It failed smog, so now is at smog repair shop, i had to replace eqr, and have them route vac lines correctly, then said not getting any vac reading, and should get 16-18 ? so i went to dealership to see wht crate motor spec for, and found it needed dual plane manifold, visually is the same performer intake as the single plane? After installed dropped dist. and it felt a wobble, it fell in, but left a thin gap, i tried shims, and didnt chg anything ? Any help is much appreciated. thanks
 

AuroraGirl

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if your carb makes no vacuum at idle(uhh..) then you have issues yes. I could see you having a improper carb install or gasket interferance of some kind. because a dual plane intake is making the amount of overlap on your intake and exhaust valves less common and feeds 4 cylinders at a time on one half the carb. notice how the opening is split? makes it so an engine does okay across wide RPM range esp for making power. a single plane can send air into an engine quicker with less obstruction = more power, really likes a stroked engine.
your distributor... did it click in properly? you said wobble. was it like an engagement or slippage? I would describe mine as A smooth but not overpowered shift from a trans, but in your hand on an engine. Distinct. Almost like a c clip on an axle when you push it in.


edit: im concerned if you have a no vacuum on your engine problem when you also say the distributor didnt engage properly, because there is one component that combines both of those and you dont want me to say it out loud
 

HotRodPC

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Is it possible the smog guys were on a ported vacuum port where it doesn't have vacuum unless you come off idle?

If the distributor has a gap, I'd make sure it's synched properly in the oil pump drive shaft. Normally that's the problem when a dizzy doesn't sit all the way down properly.


BTW, you didn't waste any money swapping to a dual plane. Single plane should be considered race only and doesn't even make good power until 2500rpm. You need the low end off idle grunt so dual plane is what you needed to begin with.
 

Bextreme04

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I have crate 350, with edelbrock single plane manifold, and had passed smog the last 2 times, well i chg carb to edelbrock 1400, from quadrajet. It failed smog, so now is at smog repair shop, i had to replace eqr, and have them route vac lines correctly, then said not getting any vac reading, and should get 16-18 ? so i went to dealership to see wht crate motor spec for, and found it needed dual plane manifold, visually is the same performer intake as the single plane? After installed dropped dist. and it felt a wobble, it fell in, but left a thin gap, i tried shims, and didnt chg anything ? Any help is much appreciated. thanks

The left port on the Edelbrock carb is timed vacuum, which means it is similar to manifold vacuum but only becomes unshrouded when the throttle blades open past the port. The right port is standard manifold vacuum and should show vacuum at idle with the throttle blades closed. If you actually had no vacuum, the truck would not run at all. The smog shop obviously doesn't know what the heck they are doing. Why did it fail? Visual or actual emissions? Did you have someone actually tune the carb after installation?

Pics would help for us to see what your vacuum routing is and what you are talking about on the distributor.
 

HotRodPC

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The left port on the Edelbrock carb is timed vacuum, which means it is similar to manifold vacuum but only becomes unshrouded when the throttle blades open past the port. The right port is standard manifold vacuum and should show vacuum at idle with the throttle blades closed. If you actually had no vacuum, the truck would not run at all. The smog shop obviously doesn't know what the heck they are doing. Why did it fail? Visual or actual emissions? Did you have someone actually tune the carb after installation?

Pics would help for us to see what your vacuum routing is and what you are talking about on the distributor.
I've never heard that port called timed vacuum. Always heard it called ported vacuum. No Vacuum until you come off idle and throttle blades move as you said. Learn something new everyday.
 

Bextreme04

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I've never heard that port called timed vacuum. Always heard it called ported vacuum. No Vacuum until you come off idle and throttle blades move as you said. Learn something new everyday.
Timed Vacuum and ported vacuum are usually the same thing. All of the edlebrock stuff I've seen lists it as timed vacuum in their manual and diagrams.
 

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