Exhaust Blackout

**Jack H.** · June 6, 2003, 12:00 PM

Re: Exhaust Blackout

An excellent pictorial resource for undercarriage detail is your copy of Noland Adams' Complete Corvette Restoration, Vol 2. In each model year chapter, Noland supplies a GM photo of the car's undercarriage. Though the pix are B&W and relatively small in size, careful study (sometimes with a magnifying glass) can reveal a LOT of interesting trivia about what was blacked out and how.

For example, if you study the front sway bar in these shots, you'll notice random sploches/blobs indicating the BO job was done quick & dirty allowing paint to run/pool/sag....

**John H.** · June 6, 2003, 01:04 PM

Re: Exhaust Blackout

Rob -

Ignoring for the moment what the JG says, the entire lower surface of the exhaust system was NOT blacked-out, nor was there any "mitting" application of blackout paint (another "urban legend"). The top and outboard sides of the mufflers were sloppily sprayed with "chassis black" paint (from the top, with the chassis fully assembled) in the last station on the Chassis Line, prior to body drop. Some day the descriptions in the JG's will become aligned with how it was really done - clearly visible in archival GM photos, and known to guys that were there at the time (like me)

**Gary B.** · June 6, 2003, 02:54 PM

John; a clarification question

John,

Am I correct that the surface of the muffler that faces the ground did not receive any black-out, nor did the front or rear vertical ends?

Gary

**John H.** · June 7, 2003, 12:41 PM

Re: John; a clarification question

Gary -

This was not any sort of precision operation, and the coverage varied widely, including drips and sags that resulted from spraying the cheapest imaginable paint directly on oily parts. The "intent" of the operation was to "hide" the shiny muffler shell visible in the side view behind the tire for "showroom appearance".

**Patrick H.** · June 9, 2003, 01:35 PM

Re: Exhaust Blackout - Legends die hard.

John,

At the SS Regional this past weekend, I had an older and respected NCRS (black hat x3) judge telling me all about how he even talked to the guy who at St. Louis used some type of "mitt-on-a-wand" for the blackout on the exhaust pipes and mufflers, allegedly from below. I tried to politely explain your theory, but you'd have thought I pi**ed in his Bloody Mary and thrown it in his face. I asked who told him, and how he came about the information, and he "swore" that he had talked 20 years ago with guys who had been there.

Whatever.

Patrick

**John H.** · June 9, 2003, 03:51 PM

Re: Exhaust Blackout - Legends die hard.

Patrick -

Yup, I understand - legends die hard. I was there, and that cheap stuff (which would stain your hands something fierce) was airless-sprayed with a pneumatic Johnstone pump out of a 55-gallon drum. Anyone who ever worked in an assembly plant (as I did for 37 years) would know better than to think that anyone would use either a "mitt" or a "brush on a stick" or a "mop-head on a handle" to apply any kind of paint, especially from below - there'd be a walkout over that one in short order. Too bad George Barlos is no longer with us - he could also help with "correct" process descriptions and dispel some of the "legends".

**Patrick H.** · June 9, 2003, 05:11 PM

Re: Exhaust Blackout - Legends die hard.

Yup.

The guy swore he was correct. I won't say who it was, but he is very well known to the NCRS crowd. He gave the same old story about the front sway bar, exhaust pipes and mufflers.

I think he read it in Noland's book. But he still acted like I personally offended him by even questioning the source of his information.

PH

**Art A.** · June 9, 2003, 10:53 PM

Show me the money.................................

.......or in this case, the part number and procedure IN THE AIM. EVERY part ( except for the air in the tires) put on at assembly had a part number and a AIM instruction in order to assemble said parts.

So this debate can be settled---show me the documentation---it's as simple as that.

Art

**Patrick H.** · June 9, 2003, 11:35 PM

Re: Show me the money.............................

Art,

Do ANY AIM's reference ANY type of blackout? We know it was done, but now you get to the question of "how much" and "when" and "where." I say we know it because we've seen it. Even John saw it, but the method varied greatly from the Urban Legend Mitt.

Patrick

**John H.** · June 10, 2003, 04:08 PM

Re: Show me the money.............................

Art -

It was one of the many locally-documented "process instructions" passed along by the Resident Engineer; somewhere in the (now long-gone) time-study files of the St. Louis I.E. Department, there was a direct labor allowance notation to perform that operation, which was part of the direct labor budget roll-up. Chevrolet had no Central Office group that organized those things - they were local. Not until GMAD took over the Chevrolet plants was any of that documented at a Central Office level; GMAD had a Central Office Process Engineering Department that issued thousands of "Process Sheets" (like Fisher Body O.D. Sheets) that documented every last operation required to build the car. GMAD essentially built cars under contract to Chevrolet, and they got paid for every single fractional part of a minute (and every bit of material) it took to build the car; if Chevrolet didn't document the requirement to GMAD, it didn't happen in the plant. GMAD based their direct labor budget buildup on actually building the car during Prototype and Pilot, not what was in the Chevrolet A.I.M.

**Art A.** · June 11, 2003, 09:49 PM

Re: Show me the money.............................

John, I agree with your analysis. I wasn't going to try to educate the world about the inner workings of the plant procedures . I guess I was wrong in implying that it was IN the AIM. If you will note my last sentence-----I asked, ----- "show me the documentation", which in reality would be the "Process Sheets" and/or any other assembly plant docs.
I guess I'm just tired of hearing about this mitt ****.
Sorry I was not clearer
Art

**John H.** · June 12, 2003, 12:13 PM

Re: Show me the money.............................

Art -

Maybe there's an eBay or retail opportunity here - lessee, we could buy a bunch of car wash "mitts", dip them in cheap, sticky old "chassis black" paint, and list them as "genuine NOS St. Louis blackout mitts"; could work with mops too, but they'd be harder to package

**Art A.** · June 12, 2003, 04:35 PM

Re: Show me the money.............................

Great idea John. Of course they would have to be "union made" and have Bobbyjoe first shift---- written on the cuff to look NOS.

Art

**Patrick H.** · June 12, 2003, 07:47 PM

Re: Show me the money.............................

Art,

It's going to be hard to get rid of the "Mitt Sh*t" when only a small portion of the Corvette hobby visits this board, and you have 300-400 level "Master Judges" teaching "Mitt Sh*t" in their classes at every meet. As I mentioned, I just tried to correct the "teacher" in his "class" and it wasn't pretty.

Urban Legends die hard. Real hard.

PH

Exhaust Blackout

Exhaust Blackout

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