Muffler Black Out Treatment?

[Tom Freeman]

I recently read about a muffler black out treatment in regards to a 74 Vette. I am assuming that this is a process to attempt to hide the muffler so it is not so obvious from the rear. Is this a factory procedure? If so, what years was it applied to and what is the process?

tom...

[Casey Andersen]

Re: Muffler Black Out Treatment?

Tom, as far as I know the mufflers were blacked out using a process called mitting. They would wipe down the system with black paint. The process was used at least from 63-82. Hope this helps. Casey Andersen

[Robert C.]

Re: Muffler Black Out Treatment?

Tom, I don't believe the blackout was "mitted" on. It was sprayed on the bottom of the muffler. Overspray resulted in the surrounding area.This was a factory proceedure.


NCRS-Texas Chapter

[Mel Goff #33968]

Re: Muffler Black Out Treatment?

Tom...

Can you recommend any sources that reference this "blacking out" procedure as being factory applied to the mufflers? I have a '74 and the mufflers/pipes are pretty nasty looking from the rear (which is what most people see) from this 400/HP BB.......Any direction to the above would be appreciated.

Thanks........Mel

[Tom Freeman]

Re: Muffler Black Out Treatment?

Mel, the first and only reference I ever saw on this process was in reference to a discussion on the spare tire carrier on a 74. They were talking about over-spray from the muffler black out process getting on the carrier. Had never heard of it before.

Those shinney mufflers can look out of place back there. Anyone know what type of paint was used?

tom...

[Jeff Gunn #29146]

Re: Muffler Black Out Treatment?

All the '73-'74 Judging Reference Guide says is "The mufflers are painted with black-out spray to even their appearance from the rear". My '74 had the original exhaust pipes (even the '74-only resonators) but the mufflers had been cut off and replaced, so I can't tell you from experience. Have you checked some of the '73-'77 Fact Manual type books for pictures? I think it was just cheap spray paint they used in a hap-hazard fashion, kind of like the underhood blackout treatment. Jeff


Jeff's '74 Corvette Restoration Project

[Tony H.]

Re: Muffler Black Out Treatment?

I would try the barBQ black paint that is sold at stores like Home Depot or Builders Square to perform the black out operation.

I have seen muffler black out on the mufflers of C4s as well.

[Dave S.]

Re: Muffler Black Out Treatment?

I have used Krylon semi flat black applied after a good hand wash w/ turpentine on a rag to clean any oil film. The heat from the system will bake it on quickly. Apply to the bottom rear and bottom of the oval exterior. I don't believe there is any exact method as this was done by different workers each with their own technique. My suggestion would be to protect the quarter panel and spare tire carrier from overspray as there is no specific judging requirement to have any overspray.

[Erich A. Meyer]

Re: Muffler Black Out Treatment?

I am the original owner of a 1972 Bowtie car. My mufflers are blacked out although some rust is coming through now afer 46,000 miles. I will admit that I have touched up the muffler blacking to keep it looking original. I use Dupli-Color High Heat spray can in flat black. This is available in most automotive supply stores, resists salt and humidity and withstands heat to 1200 deg F. I found it works well and looks very original. If you are careful, no masking of adjacent parts is required if only a touch up is required.