Vacuum diagram for 1980 super six 2BB?

shadango

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I am trying to make sure our vac lines are correct....the car WAS a 1 BBL, we converted to super six with the 2 bbl

I can find a 1980 1 BBL diagram, and a 1978 2 BBL diagram

Problem is, the 1978 is different than the 1980 to begin with, plus factor in the 2 BBL.

There has to be a 1980 2 BBL diagram somewhere, doesnt there?
 

DCAspen

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I think they had the 2 barrel option in 1980 in Canada only,Someone up north may have a service manual that has the info your looking for.
 

AJ/FormS

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Try 77. My SS came from a 77. I only have 3 circuits on mine; the vacuum advance, the EGR,and the thermactor. No air pump,no cat, no A/C,no canister, no nuttin else,lol. The EGR is controlled by a thermo-switch in the rad.
 

BudW

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The vacuum diagrams for most all of the FMJ’s fall under two different groups, Lean Burn, or not.

The newer the car, means another component added onto the list of things, but for the most part, they are all the same.


On the side of the BBD, there is a port coming out by the choke rod.
That port goes to the vacuum advance - either directly or indirectly.

Most cars that vacuum hose going to a black/metal square (the OSAC valve) attached to the air cleaner – but that part can be bypassed with no ill effect (but does matter in California Emission Inspections).
77 OSAC vv 5.JPG

Yours might also have a TIC valve (Thermal Ignition Control).
77 TIC vv 4.JPG

77 OSAC vv 1.JPG

77 TIC vv 1.JPG

77 OSAC vv 2.JPG

77 OSAC vv 3.JPG

77 OSAC vv 4.JPG

77 TIC vv 2.JPG

77 TIC vv 3.JPG


Personally, I would leave the OSAC and TIC valves in place and bypass both.
When time for inspection comes, remove your “bypass hose” and hook the other two back in place.
BudW
 

shadango

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Try 77. My SS came from a 77. I only have 3 circuits on mine; the vacuum advance, the EGR,and the thermactor. No air pump,no cat, no A/C,no canister, no nuttin else,lol. The EGR is controlled by a thermo-switch in the rad.

The issue is we are trying to keep all the emissions crap for now......and cant find a 2bbl slant 6/1980 diagram......I did find a 1980 318 2 BBl diagrm..thinking that might work?

http://repairguide.autozone.com/zne...00c152/80/08/7a/b4/large/0900c15280087ab4.gif
 

shadango

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It should.
I have no data for '80 or '81 vehicles.

Thanks.

I found a set of drawings for a Carter BBD carb , a drawing for a 1980 2bbl 318 and a 1980 1 bbl 225.....hoping to make some headway this way. The port on the carb we have that is supposed to be for the "cannister purge hose" is too small for the hose coming from our cannister......that is what is throwing us right now.....figured it wont hurt leaving this disconnected and plugged for now....
 

shadango

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The vacuum diagrams for most all of the FMJ’s fall under two different groups, Lean Burn, or not.

The newer the car, means another component added onto the list of things, but for the most part, they are all the same.


On the side of the BBD, there is a port coming out by the choke rod.
That port goes to the vacuum advance - either directly or indirectly.

Most cars that vacuum hose going to a black/metal square (the OSAC valve) attached to the air cleaner – but that part can be bypassed with no ill effect (but does matter in California Emission Inspections).
View attachment 19197
Yours might also have a TIC valve (Thermal Ignition Control).
View attachment 19198
View attachment 19199
View attachment 19200
View attachment 19201
View attachment 19202
View attachment 19203
View attachment 19204
View attachment 19205

Personally, I would leave the OSAC and TIC valves in place and bypass both.
When time for inspection comes, remove your “bypass hose” and hook the other two back in place.
BudW
W dont have the TOC or OSAC valves. just the CCEV and CCEGR switches.

How are those two tested? Hate to replace if they are ok. I assume see if there is vacuum flowing when cold and then when hot since they appear to be temperature sensors?
 

BudW

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The two prong vacuum switches that screw into cooling jacket, will either switch on or switch off when car gets hot.

The three prong vacuum switches (that screw into cooling jacket) will switch from manifold vacuum to ported vacuum depending on the temperature.

Most of the time, the switches will have the vacuum prongs broken off or cracked.
Other than that, I rarely saw a defective switch

To test on car, get a vacuum gauge and apply to the downstream hose (that might take a bit to locate).
Turn on cold engine and watch vacuum gauge. It will either go up (or go down) once it reaches that pre-set temp setting.

To test off of car, is take a pan (be sure to get wife’s or GF permission first – if not, I don’t want to hear about the damages you WILL get) and place on stove. Get a hand held vacuum pump and vacuum gauge, and do the same thing.

Pouring a cup of cold water into (turned off) boiling water, will cool water down to under the switch setting.

I would not be worried about what the temp opening setting to much – just as long as it is switching due to temp difference (if that makes sense).
BudW
 
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