C3 Blackout or Carpet

[Frank B.]

Should the back wall of a 71, C3 Convertible with Air Conditioning be blacked out or body color? What is the approximate distance from the top of the carpet to the top of the wall at the center.

[Don L.]

Re: C3 Blackout or Carpet

A good question, and one for which I too am interested in an answer/solution. I hope that by posting this, it'll raise it to the top and someone will be able to help.

[Patrick H.]

Re: C3 Blackout or Carpet

Per my 71 and 72 coupes, and Dad's convertible, the "back wall" is natural (dark gray) fiberglass.

Patrick

[Frank B.]

Re: C3 Blackout or Carpet

Thanks for your reponse, but I think we need more. I looked at a 71 convertible with AC and the carpet only went up to the bottom of the Flow Through Ventilation doors which of course are blanked off being a AC car. . It was blacked out above the carpet. Convertibles may be different because of the opening of the deck lid. I would like to hear more.

[Patrick H.]

Re: C3 Blackout or Carpet

I'll double check the convertible today when I'm out there.

[Frank B.]

Re: C3 Blackout or Carpet

Patrick, thanks I am looking forward to what you find on the Convertible.

[Patrick H.]

Re: C3 Blackout or Carpet

I looked, but couldn't really tell. When I installed new carpet several years ago, it goes high enough that you really don't see the back wall enough to answer the question. So, that doesn't help you much.

The AIM "may" tell you if blackout was spec'ed to be applied.

Patrick

[Gordon H.]

Re: C3 Blackout or Carpet

On my 71 original 1 owner convert the carpet goes to the bottom of the vent doors .The fiberglass has overspray from painting the doors black .

[Chuck S.]

Re: C3 Blackout or Carpet

On my 71 original 1 owner convert the carpet goes to the bottom of the vent doors .The fiberglass has overspray from painting the doors black .

An AC car would not have the Astrovent doors; the Astrovent door openings are covered with gasketed stamped steel covers on AC cars.

In any event, the covers, and the doors, would have been prepainted before installation...I suspect the overspray you're seeing is from the blackout of the rear plenums that the doors open into.

I didn't respond to this question before, because I am unfamiliar with convertibles. But as Patrick responded, I believed the rear bulkhead would be raw fiberglass as on the coupes. GM didn't spend money to apply paint unless it was to cover "ugliness" that was easily visible...the rear bulkhead is hardly visible, and the raw fiberglass was not exactly unpleasant to see. In fact, the new cars don't even bother with blacking out the inner fenders anymore; they are raw fiberglass (don't spill any oil on them...you'll have a permanent oil stain).

Edit: Frank, I just read your later post about the blackout above the carpet on the 71 convertible. Since the rear bulkhead on a convertible is more visible when the tonneau cover is up, I suspect you are correct about that area being blacked out IF body color overspray came through the plenum onto the top of the rear bulkhead (I assume 71 converts still have the rear plenum). They would have covered any body color overspray with blackout.

[Chuck S.]

Re: C3 Blackout or Carpet

...The AIM "may" tell you if blackout was spec'ed to be applied...

Actually, Patrick, the AIM does not address any of the blackout areas. In fact, all of the paint operations are a "black box" as far as the AIM is concerned...you pretty much have to look at an original car to see what was done.

[Robert R.]

Re: C3 Blackout or Carpet

Frank and Chuck,
I hope this helps for your '71, but while looking at the '73 AIM for something else, I saw the page regarding this topic. It shows that for AC cars that the whole bulkhead gets blacked out, but for non-AC, that the vent area should be masked off.

Bob

[Patrick H.]

Re: C3 Blackout or Carpet

Frank and Chuck,
I hope this helps for your '71, but while looking at the '73 AIM for something else, I saw the page regarding this topic. It shows that for AC cars that the whole bulkhead gets blacked out, but for non-AC, that the vent area should be masked off.

Bob

Bob,

Any chance you could scan and post that? Or reference the page?

Thanks,
Patrick

[Robert R.]

Re: C3 Blackout or Carpet

Pat,
Sorry that I could not scan, but here is the info.
The page per the AIM is: Section A01 to A12 Sheet 13.
If looking at Mid America's version, this sheet appears on their page 41.

Bob

[Harmon C.]

Re: C3 Blackout or Carpet

I checked out a 71-2-73's and 75 all convertibles and all had blackout over body color from the top of the capet to 1" above the doors or plates. It stoped on both ends where the fiberglass turned to the rear.
Lyle

[Chuck S.]

Re: C3 Blackout or Carpet

Pat,
Sorry that I could not scan, but here is the info.
The page per the AIM is: Section A01 to A12 Sheet 13.
If looking at Mid America's version, this sheet appears on their page 41...

GM must have changed how the AIMs were organized.

The earlier AIMs have UPC "sections"...from the low Mid America page number you reference, that sheet should be UPC 1, or body "Bolt and Weld". Nothing in the 70 AIM fits that description...interesting.