Muffler restoration

[Michael M.]

I have an original date coded L-48 muffler, for a 1979, that's starting to rot around the tailpipe connection on the back of the muffler. Does anybody know of someone that will cut out the rot and re-galvanize the muffler, or restore it completely?

[Edward J.]

Re: Muffler restoration

Mike I have never seen or heard of anyone doing such a thing. My advice if the muffler (s) are original to the car and still good remove them and store them in a dry place. And install a new system from corvette central.

[David H.]

Re: Muffler restoration

I have an original date coded L-48 muffler, for a 1979, that's starting to rot around the tailpipe connection on the back of the muffler. Does anybody know of someone that will cut out the rot and re-galvanize the muffler, or restore it completely?

Michael

If your question is in relation to NCRS Flight Judging: Your original "untouched" muffler is just that - ORIGINAL. As such, during Flight judging, it would receive NO points deductions for Originality. Given your description, it is likely to receive some point deduction for CONDITION.

If you repair that muffler, fixing your CONDITION issue, then you likely would get NO CONDITION point deductions. However, if your "fix" is detectable, that is, you now likely have ORIGINALITY issues, this might result in point deductions for ORIGINALITY.

You don't want to chase your tail with correcting Condition / generating Originality issues.

Mufflers for your 1979 are 8 points Originality and 6 points condition.

Good News: With 4500 total Flight Judging points available, it's not going to make much difference no matter what you do.

Dave

[Michael M.]

Re: Muffler restoration

Dave,

The car has a little over 22000 miles and I've never had it judged. I'm the second owner and it was bought out of a suburb of Detroit, Age is kicking in, rubber bushings, plastic, hoses, are starting to give way. I am trying to preserve what I can, even though it's not a highly desirable year. In addition to needing to get it judged...hopefully here in Florida, I would like to start driving it more, so I'm tossed between rebuilding the original, or driving it and putting all its systems to work. I don't have a shop press, nor a lot of tools that a proper restorer uses for everything, so I would prefer to send things out, or get a correct replacement. I'm starting to keep the old parts and buying new replacement parts to keep her looking original but I have the old for and if the time comes to frame off restore the car.
In the meanwhile, if there is a trusted shop within the NCRS community, that would rebuild this water pump...please let me know.

Thank you,
Michael

[David H.]

Re: Muffler restoration

..... I'm starting to keep the old parts and buying new replacement parts to keep her looking original but I have the old .... .... trusted shop within the NCRS community, that would rebuild this water pump...please let me know Michael

Michael

Always a good idea to keep those old parts - nice to have for reference.

A search of this Tech Board should turn up water pump restorers. Driveline should have advertisements as well.

As to highly desirable year, I have a 1980, so I feel your pain. LOL

Dave

[Frank D.]

Re: Muffler restoration

I wouldn't even drive a car with a leaky exhaust system and anything you use to repair the rusted out areas will fail in no time flat...
Those of us old enough to remember the "Muffler Patch" kits (I think that is a brand name) knows that screen and Bondo like patch would only last long enough to get past state inspection. 3 days was a good run for that Bubba repair.

[Michael M.]

Re: Muffler restoration

Dave,
I've received some suggestions on the water pump issue, but I'm in North Florida, and the two suggestions are on the Pacific coast, or New England, not really specific to the cause either as it seems. I will have to read all my old drivelines and see. The issue on the mufflers is only on the passenger side, and is only rotting around the weld that holds the tail pipe, but now the muffler rattles on the pipe...and I don't have to tell you how annoying that can be on my pristine little toy. None the less, if I don't get it judged soon it might not matter. Might just take them and the clamps, soak them in some evaporust, let them dry, and shrink wrap them for another day. If I do that I might as well put a straight pipe where the date coded catalytic converter is and save that too. Post judging of course. Florida chapter doesn't seem to do much, according to their website, except for a winter meet, hope I'm wrong...looking into joining them too. I started my Corvette dreams looking for a Yellow '80 L82, and ended up with my yellow '79 with spoilers, both have a cool look; hell, they all have a cool look!
Thanks again,
Michael

[Michael M.]

Re: Muffler restoration

I was thinking more along the lines of cutting out the welds on the back of the muffler, and around the tailpipe, and putting a new piece of metal with new welds...no bubba repairs.

[Joe L.]

Re: Muffler restoration

I was thinking more along the lines of cutting out the welds on the back of the muffler, and around the tailpipe, and putting a new piece of metal with new welds...no bubba repairs.

Michael------


The deterioration you see on this muffler is just "the tip of the iceberg". Unseen is very likely a lot more deterioration. Some things just wear out and, for all practical purposes, are not repairable or restorable. Mufflers are one of these things. If you plan to "trailer queen" the car, then repair the muffler. If you plan to drive it, then replace the muffler.

[Mike E.]

[Michael M.]

Re: Muffler restoration

I'm not sure how I will proceed Joe, but thanks for the input.

Michael

[Michael M.]

Re: Muffler restoration

Thanks Mike.

[Paul D.]

Re: Muffler restoration

Not really sure why the RH side normally goes first even on catalyst equipped cars, but I'm told they do.

[Michael M.]

Re: Muffler restoration

Mike Ernst said in this thread that its due to a 'heat riser valve'. Regardless, looks like I'm going to be replacing an original muffler...

-Mike

[Paul D.]

Re: Muffler restoration

Yes, vehicles with "true" dual exhaust will always rust out on the side with the heat riser valve. This valve restricts amount of exhaust exiting the manifold while engine is cold, forcing hot exhaust to pass back under the intake manifold to warm choke stove. They are notorious for sticking partially closed and then the RH side of exhaust runs cooler and rusts quicker. Seems to me, running through a catalytic converter with one exit would even things up.