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Topic: v6 87 vs v8 87 coug or bird vacuum storage (Read 1340 times) previous topic - next topic

v6 87 vs v8 87 coug or bird vacuum storage

i think i just noticed something.

on my 87 coug resto project it was a former CFI v6.  i am updating / converting as proper as possible to a v8 application as much as humanly possible under the hood.

when it was a V6, over on the drivers side under the coolant fill container there resides the emissions solenoids.  next to the coolant fill container is a 3'' diameter "flat & round "vacuum storage container which sources vac via a red feed line.

under the passenger fender there is another vacuum storage container 4'' and round like the size of a soft ball which ties to a 3way check valve near the heater core connections to vac assist the interior "manual" hvac controls.


on my 20th, the vac storage container is also a "FLAT & ROUND 3'' diameter container but there is not another one anywhere.



i am trying to understand when "two" vacuum storage containers were used. 

are two needed if the car was optioned with "manual hvac"?
my 20th has EATC which would all be electrical driven.

if i had manual hvac would i have a second vac storage container....?

reason i ask is that i have one big round container under the pass fender of my 87 resto project and want to make sure i am meeting the original specs.
if a v8 car with manual hvac controls required a dedicated storage container, i need to add it now.

v6 87 vs v8 87 coug or bird vacuum storage

Reply #1 –
My 88 5.0 Thunderbird (EATC equipped) has two vacuum canisters: one in the passenger fenderwell for the HVAC system and one in the driver fenderwell for the cruise control.
88 Thunderbird LX: 306, Edelbrock Performer heads, Comp 266HR cam, Edelbrock Performer RPM intake, bunch of other stuff.

v6 87 vs v8 87 coug or bird vacuum storage

Reply #2 –
you almost had me going there...

the one in the driver fender well does not count, its dedicated just to cruise.  it has electrical wiring to work two solenoids and a pot as well.

so ,, you have one vac storage container.... with EATC.

wondering if anyone with manual heat controls,, if they have two storage containers.




looked at shop manuals yesterday, interesting how much info there "is not"

v6 87 vs v8 87 coug or bird vacuum storage

Reply #3 –
Have you compared the vacuum diagrams in the electrical and vacuum technical manual? I would think the information would be in there. I only have the 88 EVTM but I can check and see if the information is in it.
88 Thunderbird LX: 306, Edelbrock Performer heads, Comp 266HR cam, Edelbrock Performer RPM intake, bunch of other stuff.

v6 87 vs v8 87 coug or bird vacuum storage

Reply #4 –
yes and shop manuals as well,
i think there are several different vac diagrams across 83-88

for 87 i think there are 3 for each 2.3L,  3.8L and 5.0L

i got my issue solved though.
Since i dont have eatc, there is a 3way check valve that is near the heater core.  I just connected it up like it was as a 3.8L so my interior hvac stuff works.

I was getting confused on how to integrate vac into the Tab/Tad / EVR solenoids i need to mount to the rear of the pass strut tower.  then it occured to me that it doesnt matter. connect them up like factory and keep them separate from each other.

i am not installing the smog pump so the tab/tad white and black vac lines will be blocked off but electrically connected so the eec see's them.