'73 Floor Heater Duct?

[Peter G.]

What is this part called?

Sorry the attachment is not clear and somewhat fuzzy.

It is black plastic and it comes from the heater box behind the dash and exits just behind the radio on the console on the passenger side floor.

Possibly when the heater core was replaced the part was either lost or damaged and not put back on the car?

Where can you get this part? Can it be replaced it without pulling the dash to access the heater box? Does it snap on or is it glued? Is it part of a larger piece?

Where does the radio amplifier go as it is sitting in the path of the duct bolted to the floor?

Sorry for all the questions.

Thanks.

[Harmon C.]

Re: '73 Floor Heater Duct?

The radio amplifier was installed high on the firewall above the kick plate. You may find another one in that location and if you do I need one. Remove the RH dash to see it as it is above all the heater box. The duct I think may be different on A/C cars and I'm not clear on what your missing.
Do you mean the duct that puts heat on the gage cluster from above?

[Jack H.]

Re: '73 Floor Heater Duct?

The part is called: "Duct, Cabin Heater". You'll find it listed in the Parts & Accessories Catalog in Section 9.786. There are different parts for different years (some downward compatible with factory original) as well as version of the part for non-A/C vs. A/C equipped cars.

I don't think you're going to find it from GM and it's NOT listed in the Dr. Rebuild catalog (one of the better places to look for dash ducting components). So, that leaves your local Corvette parts specialty shops including: Corvette City, Corvettes Only, and Corvel Automotive in the Denver area for a used original from a scrap yard car...

The other answer about the 'amplifier' is correct. It's not really an 'amplifier', it's a voltage to current converter for the radio's final audio drive to the speaker. What you want/need depends on whether the car was equipped with base AM/FM or optionial stereo radio. The base radio had a 'convector' which is essentially a DS-501 transistor mounted on a heat sink that cable connected to radio chassis and attached to the windshield frame below the RH dash pad.

If the car was equipped with optional AM/FM/Stereo, what you got is year specfic, but the big picture is early Sharks had a second 'box' in addition to the convector that also mounted under the dash above the heater box. The 'box' provided FM de-multiplex to recover the secondary stereo audio channel and provided final audio drive to the second speaker.

Later era Shark cars benefitted from electronics integration and the de-mux circuitry moved into the main radio chassis leaving only a 2-channel 'convector' cable connected outside (two DS-501 transistors on a single heat sink).

[Peter G.]

Re: '73 Floor Heater Duct?

Didn't know what to call the finned external box? The radio is a original AM/FM mono with two front speakers in the top of the top dash pad.

Missing item is just the 3 inch plastic that directs heater air to the floor. Is this a separate piece from the big heater box that the heater core sits inside?

If I look at a Corvette salvage yard would this piece be affixed to the big box? Or a small piece in itself?

[Peter G.]

Re: '73 Floor Heater Duct?

Thanks, guys I will keep my open.

[Joe L.]

Re: '73 Floor Heater Duct?

What is this part called?

Sorry the attachment is not clear and somewhat fuzzy.

It is black plastic and it comes from the heater box behind the dash and exits just behind the radio on the console on the passenger side floor.

Possibly when the heater core was replaced the part was either lost or damaged and not put back on the car?

Where can you get this part? Can it be replaced it without pulling the dash to access the heater box? Does it snap on or is it glued? Is it part of a larger piece?

Where does the radio amplifier go as it is sitting in the path of the duct bolted to the floor?

Sorry for all the questions.

Thanks.

Peter-----


Assuming the part in the center of the picture is the part you seek (if this photo was taken of your car, I don't see why you need it), this part was GM #3963797. It was discontinued from SERVICE in May, 1977 and replaced by GM #459362, a differently configured but fully functional piece. Unfortunately, that part was discontinued without supercession in January, 1993.

I'd say that a used parts source like Pacific Corvette or those mentioned by others is going to be your best bet for a replacement.

The duct can be installed without removing the heater box. However, it cannot be installed without removing the center cluster and radio head unit. This also requires removal of the right side dash pad.

The duct is attached by a "slide-in" clip on the right side and a single screw on the left side.

[Peter G.]

Re: '73 Floor Heater Duct?

Thanks Joe, that is what I wanted to know.

The picture is not of my car and was taken on a low mile 25k mile original owner '73 L48 4 speed car who wanted me to evaluate his car for NCRS Judging.

Now that I think of the car, his car was a non-a/c car. Would that make a difference?

[Joe L.]

Re: '73 Floor Heater Duct?

Thanks Joe, that is what I wanted to know.

The picture is not of my car and was taken on a low mile 25k mile original owner '73 L48 4 speed car who wanted me to evaluate his car for NCRS Judging.

Now that I think of the car, his car was a non-a/c car. Would that make a difference?

Peter-----


As far as I can tell, this piece was the same for C-60 and non-C-60 applications.

[Peter G.]

Re: '73 Floor Heater Duct?

Thanks Joe for the response.

http://cgi.ebay.com/ebaymotors/ws/eB...m=370268316889

Is this the piece I am missing? It sure doesn't look like the picture I posted, but maybe that part is larger than I thought and picture taken at a different angle?

[Joe L.]

Re: '73 Floor Heater Duct?

Thanks Joe for the response.

http://cgi.ebay.com/ebaymotors/ws/eB...m=370268316889

Is this the piece I am missing? It sure doesn't look like the picture I posted, but maybe that part is larger than I thought and picture taken at a different angle?

Peter----


Yes, this is the part. Much of it is unseen when installed in the car. That may be why it appears large to you in the photo.

[Peter G.]

Re: '73 Floor Heater Duct?

Thanks to everyone who help me find this part and help confirm what the part was that I needed! Today I was able to purchase this missing part on eBay for a fair price.

To top it off well, the seller was a fellow NCRS member and Corvette enthusiast.

Now I need to find the energy to pull the needed parts to install this missing piece of duct work. Sounds like a good Winter project in a heated garage.