Hello everyone I am new to the corvette world I have always loved them. I finally got my chance to own one its a 1980 Corvette and yes it needs work. I am starting with the front suspension, brakes the hopefully little motor work. I did drive the car home and that was scary cause all of a sudden no brakes (hence the brake system rebuilt). Anyways I have a couple of questions as to what a couple things are hopefully I can get pics up. One is a switch of some kind its on the fire wall next to the wiper motor, and the second is a valve of some kind its in line with one of the heater hoses the goes to the heater core, this car use to have A/C so I am wondering if the valve is for that, Maybe shuts off hot water supply when the A/C is activated. Last question is there a book, magazine out there the lays out where wires, vacuum hoses etc are supposed to go on this model of car. Thanks again for any help with this and any furture questions on this rebuild.

 

Yes, the bottom picture shows the "hot water shut-off valve". In '80 the valve is closed anytime that the temperature selector lever is moved all the way to cold. The mode (A/C, heat, vent, etc.) has no affect on the valve. Behind the glove box you'll find the "hot water shut-off switch" on top of the HVAC housing--it has two vacuum lines and three vacuum connections. A lever attached to the temperature selection cable operates the valve. If the lines there haven't been plugged you'll have a vacuum leak with the temperature selector all the way to cold. The system works independent of A/C and with a constantly running fan this means that you'll ALWAYS have somewhat heated air being pumped into the cabin when it is disabled.

Other than to say it is a vacuum operated electric switch I do not know the function of the switch in the first picture. I'll look at the '80 assembly manual shortly to see if I can find what it's about. I know it's not present in my '79.

 

The switch in the first pic is for the torque converter lockup. It's obviously not needed if yours has been changed to a manual transmission. If still the original (or original type) transmission however it may have been intentionally disconnected even if the lock-up works properly. This is a primitive control scheme that allowed the converter to lock even in 2nd gear. In normal street driving it would sometimes lock and unlock repeatedly and very frequently. Some found this operation annoying and disconnected the system.

Cars of that era and Corvettes in particular made GREAT use of vacuum operated systems and have an amazing number of hoses. All of these hoses and especially their connections are potential leak points. I can almost guarantee that any original hose is leaking at it connections and while they may be tiny leaks such add up!

Judging by your pics, I think it is time for you to:

1) Determine which vacuum operated systems are still installed.

2) Determine which vacuum operated systems you intend to keep functional. IMO the EVAP system should always be maintained. PCV is mandatory. Your stock dual snorkel cold air intake is a very well designed system suitable for larger displacement/higher RPM engines (within reason). EGR is controversial although I believe most will concede that its emission reductions outweigh any (if such even exists) performance hit on a street driven car. Since the EFE system only functions during warm-up there's no reason to omit; similarly the THERMAC system that draws combustion air from the "heat stove" around the stock exhaust manifold functions only during warm-up and like the previous is there to make warm-up as quick as possible. A.I.R. does take some engine power to operate (I believe most greatly exaggerate just how much) but since I believe it is bypassed at wide-open throttle it has very little impact on final performance while greatly reducing unburned fuel in the exhaust. Cruise control, if present, is vacuum operated as are the headlamp doors. All mode selection in the HVAC is operated by vacuum as is the previously mentioned hot-water shutoff system.

3) Get all new vacuum hoses for the systems you intend to retain. Doc Rebuild is an EXCELLENT source for the hoses--they are sold by the system and come with excellent illustrations.

 

Here is a assembly manual.
https://willcoxcorvette.com/corvette...y-manual-59-82

 

As a final thing to add I have no problem repeating that the greatest improvement I made to my mainly stock '79 L82 was replacing all of the vacuum lines. Performance, fuel economy, starting, idling, running and comfort (FAR quieter at highway cruising speed) all improved more than the sum of previous "tune up" items like plugs/wires (both very old but not original), distributor cap, rotor, etc. With the exception of the catalytic converter (I have true dual exhaust) all of the factory emission systems are installed and functioning.

 

You will find a lot of information here. I rebuilt my car using the knowledge from this forum. I have an 80 as well. Your rebuild on the front end will make a very big change in the way the car drives. You will also get a chance to do the back end next winter. that is when it will really shine. As for the brakes just buy new lines and calipers and be done with it. You will be much happier... you will be in for a huge surprise. You can go to auto Zone and buy everything you need for this car.