1979 Models with factory D80 (air deflectors).

[Tom R.]

Looking for 1979 owners with D80, air deflectors installed. Apparently, they came with a screw/captive washer to secure the top of the air deflector to the fender. In 1978, Pace Cars did not use the screw but overtime the top of the spoiler would separate from the fender. The 1979 AIM does not show this but we are interested to hear from 1979 owners to document this deviant factory practice.

[Edward A.]

Re: 1979 Models with factory D80 (air deflectors).

Any info on the screw/captive washer? I have a 1978 and just acquired a factory rear spoiler, however it's probably for a 1978 Pace Car since it doesn't have the screw/captive washer on it. Would that be a correct conclusion? The 1979 AIM shows it does get secured to the fender with a bolt.

[Tom R.]

Re: 1979 Models with factory D80 (air deflectors).

Any info on the screw/captive washer? I have a 1978 and just acquired a factory rear spoiler, however it's probably for a 1978 Pace Car since it doesn't have the screw/captive washer on it. Would that be a correct conclusion? The 1979 AIM shows it does get secured to the fender with a bolt.

The original post referred to the "front" spoiler versus the rear. Since its post in 2014, we have confirmed that indeed 79s D80s (front) were installed with the screw/captive washer configuration.

[Edward A.]

Re: 1979 Models with factory D80 (air deflectors).

Tom,
I wasn't able to load the photos on PM so hopefully can get them to you here. The grey primer spoiler is factory OEM I just acquired which was reconditioned by the previous owner. The red spoiler is all factory OEM. The guy I bought it from told me he removed the nut and filled in the hole (grey spoiler). It looks like some sort of weld nut was attached to the spoiler so that the bolt/washer screw could attach to it from inside the rear fender. What I'm trying to determine is what size is the nut or weld nut and what size is the bolt/washer screw. I haven't been able to locate a correct description of the type bolt/washer screw used. The AIM has a GM Part Number, but I've had no luck locating it. Any assistance on the bolt/washer screw used would be greatly appreciated.

[Tom R.]

Re: 1979 Models with factory D80 (air deflectors).

Tom,
The grey primer spoiler is factory OEM I just acquired which was reconditioned by the previous owner. The red spoiler is all factory OEM. The guy I bought it from told me he removed the nut and filled in the hole (grey spoiler). It looks like some sort of weld nut was attached to the spoiler so that the bolt/washer screw could attach to it from inside the rear fender.

So is the red spoiler showing the weld nut?
Is the metal bar on the gray spoiler cut off at the end?
Where's the bar on the red spoiler?
Is the raised surface at the tip of the gray spoiler where the weld nut hole filled in?

What I'm trying to determine is what size is the nut or weld nut and what size is the bolt/washer screw. I haven't been able to locate a correct description of the type bolt/washer screw used. The AIM has a GM Part Number, but I've had no luck locating it. Any assistance on the bolt/washer screw used would be greatly appreciated.

Cross reference mounting hardware with the front spoiler. It looks like the same design was used...a riveted metal support bracket and then weld nuts used to mount on the fiberglass fender. I concluded for the front spoiler, that the mounting hardware (bolts), I secured by picking up hardware from a 67 Corvette. I'll look it up today sometime.

Show a picture of the entire inside view of the spoiler. I want to see the bar.

[Edward A.]

Re: 1979 Models with factory D80 (air deflectors).

So is the red spoiler showing the weld nut? I believe so.
Is the metal bar on the gray spoiler cut off at the end? No, I believe that is they way they were made (see expanded picture of red spoiler)
Where's the bar on the red spoiler? Uploaded another photo.
Is the raised surface at the tip of the gray spoiler where the weld nut hole filled in? I believe so.
The 'metal bar' on the factory urethane spoiler is actually two piece. Each piece is fastened to the urethane with 7 rivets. Each piece has 3 studs to attach the spoiler.

[Tom R.]

Re: 1979 Models with factory D80 (air deflectors).

So is the nut/washer assembly you need? You have a square box drawn around the stud on the red spoiler. I just went out and removed the nut/washer assembly. Looks like 5/32." I can take it over to Lowe's and measure it for sure but it could be metric. the studs on the side are pretty rusted on my Pace Car rear spoiler. May have to torch em off. LOL

Well I was curious so I found a source (link below) and went ahead and ordered a rear spoiler mounting hardware kit. I'll be curious to see what I get...$6.95.

https://corvetteparts.com/catalog?q=rear+spoiler

[Edward A.]

Re: 1979 Models with factory D80 (air deflectors).

So is the nut/washer assembly you need? You have a square box drawn around the stud on the red spoiler. I just went out and removed the nut/washer assembly. Looks like 5/32." I can take it over to Lowe's and measure it for sure but it could be metric. the studs on the side are pretty rusted on my Pace Car rear spoiler. May have to torch em off. LOL

Tom,
Disregard the 'blue' square box. That was drawn by someone else. Yes I am needing the nut/washer assembly, however it looks more like some sort of weld nut that is somehow attached (glued) to the inside of the spoiler ends. The AIM doesn't have a part number for it as I guess it was considered part of the spoiler assembly. The screw and retainer (washer) is listed as part numbers 9418857 Screw and 476253 Retainer. The holes required for the side screws are the same as the holes on top for the spoiler studs, 1/64 DIA.

I've searched for the screw using the GM Part number 9418857 and found it to be the same screw used a 1969 Camaro to attach the Auto. Trans-Neutral Safety switch. I found they sell those screws (GM #9418857) on ebay. However, it's the nut that has me puzzled. Those shouldn't be studs attaching the side of the spoiler, it should be the screw? ..and I wouldn't want you to damage your spoiler taking it out. Thanks lol!

[Edward A.]

Re: 1979 Models with factory D80 (air deflectors).

[Tom R.]

Re: 1979 Models with factory D80 (air deflectors).

Tom,
Disregard the 'blue' square box. That was drawn by someone else. Yes I am needing the nut/washer assembly, however it looks more like some sort of weld nut that is somehow attached (glued) to the inside of the spoiler ends. The AIM doesn't have a part number for it as I guess it was considered part of the spoiler assembly. The screw and retainer (washer) is listed as part numbers 9418857 Screw and 476253 Retainer. The holes required for the side screws are the same as the holes on top for the spoiler studs, 1/64 DIA.

I've searched for the screw using the GM Part number 9418857 and found it to be the same screw used a 1969 Camaro to attach the Auto. Trans-Neutral Safety switch. I found they sell those screws (GM #9418857) on ebay. However, it's the nut that has me puzzled. Those shouldn't be studs attaching the side of the spoiler, it should be the screw? ..and I wouldn't want you to damage your spoiler taking it out. Thanks lol!

That's why I ordered the kit!

[Edward A.]

Re: 1979 Models with factory D80 (air deflectors).

I haven't seen a kit for the rear factory urethane spoiler. Nobody even sells it anymore and the fiberglass one's don't use the side screws.

[Tom R.]

Re: 1979 Models with factory D80 (air deflectors).

I got into all that with the front spoiler as I dismembered the entire configuration. But I was fortunate enough to piecemeal the metal support brackets with Dr Rebuild (OEm stuff), figured out the mounting hardware and then proceeded to drill out the rivets, remove the rusted metal supports and ready it for re-assembly. I have a box of parts here just finished looking at to see if anything as any similarity to the rear. Of course, it doesn't.

[Edward A.]

Re: 1979 Models with factory D80 (air deflectors).

Thanks Tom. I expect I'll get there too, want to put the D80 front spoiler on mine too eventually, although I it should be easier than the rear since I have seen a lot of urethane front spoilers out there (I've checked). The D80 option is the only thing missing for my 1979 L82 to make it look like my first 1979 L82 I had 30 years ago. I'll get there eventually. I was real lucky to find this on with only 25,000 miles and pretty much 100% original. It's like a time machine. Are you coming to the NCRS National Convention this year?

[Tom R.]

Re: 1979 Models with factory D80 (air deflectors).

The thread size of the screw/nut assembly that secures the deflector to the top of the rear deck is a 10-24.

[Tom R.]

Re: 1979 Models with factory D80 (air deflectors).

So got the rear spoiler mounting hardware kit from Davie sCorvette. it included six 10-24 captured nuts and washers. Two 1/4 20 bolts with 10-24 thread were included for the fender mounts. The finish is cadmium silver so departs from original factory but not judged. Blast and refinish in black oxide and it will be indistinguishable from original mounting hardware.