Help! Vacuum Hose Diagram

[RonzBoyz]

I should have taken pictures or drawn a diagram of the setup before…….

I pulled the heads on my 85 Vette. A task in its self! Most is back in its place, the car runs fine so the point. I do not know the layout of the vacuum hoses. Some were/are cracked, broken or not hooked up before and especially not now.

I need a layout/diagram of the vacuum hose system for my 85 Vette.

Thanks, RonzBoyz

 

[vetteoz]

Vacuum lines schematics

 

[RonzBoyz]

View attachment 21301


The diagrams were a great help!! THANKS.
A modification for my setup Vette.

The EGR Sol is in the back by the HVAC line. I hooked that up, the EGR valve to the EGR Sol and "T"ed that off to the cruise control and that "T"ed to the ball canister by the vapor canister.

I'll see after a drive.

Next project, heating/cooling!!


Thanks
RonzBoyz

 

[vetteoz]

The EGR Sol is in the back by the HVAC line. I hooked that up, the EGR valve to the EGR Sol and "T"ed that off to the cruise control and that "T"ed to the ball canister by the vapor canister.

Be aware that with that setup the vac ball will not hold vac as intended ; it will only see what vac the engine is pulling
The HVAC/ cruise / vac ball are off a line that has a check valve so vac is mantained when engine vac drops as in accel .Rubber hose to the side goes to cruise and ball; rear line through firewall to HVAC

 

[RonzBoyz]

Be aware that with that setup the vac ball will not hold vac as intended ; it will only see what vac the engine is pulling
The HVAC/ cruise / vac ball are off a line that has a check valve so vac is mantained when engine vac drops as in accel .Rubber hose to the side goes to cruise and ball; rear line through firewall to HVAC

View attachment 21303

Vettoz, thanks again in advance.

I find 3 vacumm sources noted, A and B by the distributer and C in the front.
To which line should I attach #8 small hose cruise control. Not the big one.

As far as you can see, is # 1 hooked up okay? There are two lines, a small and a big. The electric plug is facing forward.

Any magic on heating/cooling? The thing runs around 210'F.

RonzBoyz

 

[vetteoz]

As shown in the pic the line from one of the rear ports goes to the HVAC spliting at the check valve to connect to the cruise / vac ball.The other rear port goes to the FPR
I would put EGR /FPR on one ; HVAC /cruise on the other and the front one under the TB does the vac cans on the emission plumbing under the headlight

210 is normal ; fans are not programmed to run until 228
you can either get a custom chip burnt or install a mech switch in the head to turn fans on at a lower temp

 

[RonzBoyz]

View attachment 21304

This hose "X" that I have been trying to place, which was originally laying in the area of the two draw points, A & B on the diagram, may have been modified before my time.

The HVAC line to which a check valve is connected would be about where? I may just cap it off.

I do appreciate your patience.

RonzBoyz

 

[vetteoz]

The HVAC line to which a check valve is connected would be about where? I may just cap it off.

The grey cap shown on the check valve in the pic is on the hard plastic line that runs in the wiring harness across the firewall and goes through a bulkhead connector into / under the dash for HVAC
No need to cap it off ; if open and no vac to HVAC, vents will stay in the default defrost position
New generic check valve $5 from NAPA

 

[RonzBoyz]

The grey cap shown on the check valve in the pic is on the hard plastic line that runs in the wiring harness across the firewall and goes through a bulkhead connector into / under the dash for HVAC
No need to cap it off ; if open and no vac to HVAC, vents will stay in the default defrost position
New generic check valve $5 from NAPA

Hey Oz

The HVAC is good, vent air flow changes as I slide the selecter on the climate control panel.

The lone hose I am refering to is from the cruise control and hanging, now. I ment cap off the cruise control.

RonzBoyz

 

[vetteoz]

The HVAC is good, vent air flow changes as I slide the selecter on the climate control panel.

If so one of the rear ports must be connected to the HVAC line.Connect the cruise hose to that line and you will be right

 

[RonzBoyz]

If so one of the rear ports must be connected to the HVAC line.Connect the cruise hose to that line and you will be right

After I got what you ment with the check valve, which I do not have or can nto locate, yet, I have capped the line.

It looks like the HVAC is hooked directly to the back feed, without the check valve.

Thanks for your time and interest. It has made the project easier.

On the heating/cooling part, 210 normal? Can I not just change the sending plug to a lower temp? You mentioned a reprogramming.

Later, RonzBoyz

I can now heat up the autobahn at 100mph plus, with the temp over 210 and feel at ease. Any quick poewr increase pointers. I am currently running straight pipes. That seems to give a little bit more and sounds mean.

 

[vetteoz]

Can I not just change the sending plug to a lower temp? .

85 only has computer control of fans with a mech over ride switch in the pass side head between # 6+ 8
You could simply change that to a lower on temp one if you wished.
The fans when computer controlled turn off at 30 mph; if running from a mech switch at a lower setting they would run full time until cut off temp reached
Long tube headers are the best bang for $$$ mod on stock TPI engines