Vacuum line questions

[85 SQ]

I have an 85 GMC Sierra was a 305 truck now has a Goodwrench 350 . I am deleting the excess vacuum lines and smog crap . I know I need to run vacuum for the vac advance and brake booster and also retain the pvc valve . My question is what other vacuum lines do I need to keep .

 

[gotyourgoat]

What is currently in the truck and does it run?

Also you want the short, long or most argumentative versions to the yank n smog question?

 

[Rusty Nail]

Are there vacuum hoses at your thermostat housing?

You'll need vacuum hose for the windshield warshers and possibly the EFE valve had one?
Cruise control gets a vacuum hose and so does the transmission modulator...
Umm....
There was a hose to the air cleaner.
HVAC has at least two underhood.
EGR in 1985..
The carburetor .

 

[85 SQ]

Are there vacuum hoses at your thermostat housing?

You'll need vacuum hose for the windshield warshers and possibly the EFE valve had one?
Cruise control gets a vacuum hose and so does the transmission modulator...
Umm....
There was a hose to the air cleaner.
HVAC has at least two underhood.
EGR in 1985..
The carburetor .

 

[85 SQ]

Goodwrench 350 was a 305 truck . Using a edelbrock rpm intake ( no egr ) edelbrock 1405 600 CFM carb . No cruise I believe it has an efe . There was vacuume hoses on the old thermostat housing the one I have installed does not have them . Also using a sandwich style air cleaner so no lines to that .

 

[HotRodPC]

And of course if you've removed all that, you've removed the AIR pump too so no diverter valve. If you're running a Th350 or Th400 Auto trans and need a manifold vac line for the vac modulator. You'll also need vacuum going to the air handler under the dash to operate the blend doors for the Heat, Air and defroster.

 

[HotRodPC]

Goodwrench 350 was a 305 truck . Using a edelbrock rpm intake ( no egr ) edelbrock 1405 600 CFM carb . No cruise I believe it has an efe . There was vacuume hoses on the old thermostat housing the one I have installed does not have them . Also using a sandwich style air cleaner so no lines to that .

The only reason you'd have Vac hoses at the Thermostat housing is for the TVS (Thermal Vac Switch) to disable Vac Advance, Dirverter Valve and EGR operation until the engine was warmed up. So for what you're doing, you don't need the TVS unless you want to disable vac advance until the engine is warmed up.

 

[Rusty Nail]

Vacuum hoses have two ends and everybody should be accounted for to avoid leaks..
Make certain your EFE valve is full OPEN - since that's what the vacuum line did , was open it.
If you have removed or capped THAT hose, you may have inadvertently created an exhaust restriction lol.
But whatever!

 

[85 SQ]

Vacuum hoses have two ends and everybody should be accounted for to avoid leaks..
Make certain your EFE valve is full OPEN - since that's what the vacuum line did , was open it.
If you have removed or capped THAT hose, you may have inadvertently created an exhaust restriction lol.
But whatever!

So make sure I leave vacuum hooked up to the efe simple enough