Replacing side exhaust, recommendations please

[Michael J.]

I have decided it is time to replace my side exhausts on my '67, yes they are original as per tank sheet. They look very old, rusted, corroded, etc. I am thinking I could do this myself, it looks pretty simple, covers easy to remove and the exhaust units look like they are one-piece. What replacement part and vendor is the best for this, as this is a top flight car and I would like to keep it that way? Thanks.

[Larry S.]

Re: Replacing side exhaust, recommendations please

Michael, the side pipes are pretty easy to replace. To answer your question, I'd spring for a set of NOS pipes. Even now, as vendors claim to have copied the original design and sound perfectly, you're going to find that their pipes are noticeably louder than the originals. As you know, original side pipes certainly aren't quiet anyway, but do you want them to be noticeably louder?

[Michael J.]

Re: Replacing side exhaust, recommendations please

OK, I know they have to be carbon steel, not aluminized or stainless, in order not to lose points on the replacements. My covers are in great shape and are originals, so NOS pipes would be the way to go. Where do you find the NOS ones?

[Wayne M.]

Re: Replacing side exhaust, recommendations please

OK, I know they have to be carbon steel, not aluminized or stainless, in order not to lose points on the replacements. My covers are in great shape and are originals, so NOS pipes would be the way to go. Where do you find the NOS ones?

I second Larry's suggestion for NOS. I see you'll probably be installing on your '67 L71, so you need the BB N14 pipes.

I noticed a set of 969/970's in the crawlway under my basement steps [bought just before GM stock exhausted (pun intended); not for sale]. Mentioned to show that original (service) sets are still out there.

eBay is your best bet, but be prepared to search for 6 months and pay more than you expected.

[Larry M.]

Re: Replacing side exhaust, recommendations please

An ebay search for 'NOS side pipes' returns 22 listings, 4 of which are 1963 to 1967 NOS Corvette side pipes.

[Larry S.]

Re: Replacing side exhaust, recommendations please

I second Larry's suggestion for NOS. I see you'll probably be installing on your '67 L71, so you need the BB N14 pipes.

I noticed a set of 969/970's in the crawlway under my basement steps [bought just before GM stock exhausted (pun intended); not for sale]. Mentioned to show that original (service) sets are still out there.

eBay is your best bet, but be prepared to search for 6 months and pay more than you expected.

Thank you, Wayne. It can be a long, expensive search, but I have gotten lucky once or twice. I hate to admit it, but I was just buying and selling them for a profit. Two years ago I found a NOS set of 2.5" pipes, rocker moulding, and covers for $2200. I sold them for twice that. But if you don't need the covers and moulding, you might find the pipes for $1200 or less. Believe me, the NOS ones are well worth the effort and price.

[Larry M.]

Re: Replacing side exhaust, recommendations please

I believe than Allen's Exhaust purchased the last remaining (known) stock of NOS BB sidepipes a few years ago. They probably have a few sets left. I would call and inquire.

Also, check their website.

http://www.allencorvetteexhaustsystems.com/

Larry

[Wayne M.]

Re: Replacing side exhaust, recommendations please

An ebay search for 'NOS side pipes' returns 22 listings, 4 of which are 1963 to 1967 NOS Corvette side pipes.

Three of those NOS are for small blocks, and the big block set has been fabricated (on one side) by using the chambered portion of NOS small block pipe welded to an aftermarket header connect. Nevertheless, this might be the best to be expected in the short run.

I would think those small block N14's (if legit) should find a home soon.

[Larry S.]

Re: Replacing side exhaust, recommendations please

Three of those NOS are for small blocks, and the big block set has been fabricated (on one side) by using the chambered portion of NOS small block pipe welded to an aftermarket header connect. Nevertheless, this might be the best to be expected in the short run.

I would think those small block N14's (if legit) should find a home soon.

Yes, and that set with the fabricated piece has been on eBay forever. I would make the seller a reasonable offer (of course, he may not be a reasonable seller).

[Michael J.]

Re: Replacing side exhaust, recommendations please

OK, thanks for all the tips, it's off on another Easter Egg hunt for me on eBay and elsewhere.

[Michael J.]

Re: Replacing side exhaust, recommendations please

One last question, should the pipes have inner baffle tubes? I see that mentioned as NOS and original type. An NCRS friend told me he remembers the pipes as just being hollow tubes, with crimps for the chambering effect at regular intervals like you can see on the outside. Is there anything inside those pipes?

[Larry M.]

Re: Replacing side exhaust, recommendations please

One last question, should the pipes have inner baffle tubes? I see that mentioned as NOS and original type. An NCRS friend told me he remembers the pipes as just being hollow tubes, with crimps for the chambering effect at regular intervals like you can see on the outside. Is there anything inside those pipes?

No.

Larry

[John H.]

Re: Replacing side exhaust, recommendations please

One last question, should the pipes have inner baffle tubes? I see that mentioned as NOS and original type. An NCRS friend told me he remembers the pipes as just being hollow tubes, with crimps for the chambering effect at regular intervals like you can see on the outside. Is there anything inside those pipes?

Michael -

Yes, there is. The inner core pipe (1-7/8" diameter) has hundreds of half-moon-shaped pierced perforations that protrude into the gas flow area, and the outer pipe is crimped to the O.D. of the inner pipe to create a series of attenuation chambers between the two pipes. There are no other baffles or separate parts. If you look closely at the cut-open pipe in the bottom of the photo below, you can see the perforations in the inner core tube.

[Michael J.]

Re: Replacing side exhaust, recommendations please

Michael -

Yes, there is. The inner core pipe (1-7/8" diameter) has hundreds of half-moon-shaped pierced perforations that protrude into the gas flow area, and the outer pipe is crimped to the O.D. of the inner pipe to create a series of attenuation chambers between the two pipes. There are no other baffles or separate parts. If you look closely at the cut-open pipe in the bottom of the photo below, you can see the perforations in the inner core tube.

Thanks John, that matches the description and picture of the NOS ones I found, shown here: