Need Source Recomendations for New Exhaust Manifolds

[Greg Y.]

1966 coupe... The exhaust manifolds are in pretty bad shape. One of my winter projects is to replace these with new. As near as I can tell the casting numbers are 3747038 and 3749965. Anyone have good luck with new imported castings? Most of the used ones I see on eBay are in pretty bad shape.

Thanks in advance
Greg

[Joe L.]

Re: Need Source Recomendations for New Exhaust Manifolds

1966 coupe... The exhaust manifolds are in pretty bad shape. One of my winter projects is to replace these with new. As near as I can tell the casting numbers are 3747038 and 3749965. Anyone have good luck with new imported castings? Most of the used ones I see on eBay are in pretty bad shape.

Thanks in advance
Greg

Greg------


I agree with your inclination to use NEW exhaust manifolds. As you have noticed a lot of the used ones are rough, many with ugly, corrosion-induced pitting. I would NEVER use one of these. Also, you,ll find that well-used exhaust manifolds have a tendency to cracking, especially when tightening down the manifold-to-exhaust pipe studs.

I have never used the foreign-manufactured replacements. However, they are rather inexpensive and I expect they'll work OK. They'll never fool anyone as being originals, though, as their configuration and markings are considerably different from originals. These are simply replacement manifolds, not reproductions of the originals. If it were me, though, I'd spring for the Paragon reproductions available from Paragon, Dr. Rebuild, and others.

[Mike M.]

Re: Need Source Recomendations for New Exhaust Manifolds

imported cast iron sbc manifolds are junk. they'll warp/crack after limited miles. i had occasion to buy new 2 1/2" sbc manifolds for a street rod i'm building for one of our daughters. i've judged made in the usa repos for years in the 63-64 judging class and up until now, it was a simple matter to identify d them as repos(their top casting mold protrusions were ground off, unlike originals). imagine my surprise when the new, made in USA manifolds for the street rod arrived. mold protrusions weren't ground off and i couldn't tell they were not nos originals with a cursory exam. i got them from Paragon, a source know for quality parts, even back when richard owned paragon. mike

[Gary B.]

Re: Need Source Recomendations for New Exhaust Manifolds

Mike,

I'm not sure of the intent of your last sentence, but I've purchased a number of quality parts from Richard since he sold Paragon, and he has always been very helpful when I had special requests.

Gary

[Mike M.]

Re: Need Source Recomendations for New Exhaust Manifolds

back in the 80's and up until richard sold the Paragon business, the quality of his NOS, used and repo parts were absolutely one of the best. i damn near failed english composition in high school. i told the christiian brother i sure as hell knew what i was saying in the essays. i preferred writing about hops, the nectar of the gods, and the christian bro didn't. we are still best friends. and he still criticizes my compositions. regards, mike

[Joe L.]

Re: Need Source Recomendations for New Exhaust Manifolds

imported cast iron sbc manifolds are junk. they'll warp/crack after limited miles. i had occasion to buy new 2 1/2" sbc manifolds for a street rod i'm building for one of our daughters. i've judged made in the usa repos for years in the 63-64 judging class and up until now, it was a simple matter to identify d them as repos(their top casting mold protrusions were ground off, unlike originals). imagine my surprise when the new, made in USA manifolds for the street rod arrived. mold protrusions weren't ground off and i couldn't tell they were not nos originals with a cursory exam. i got them from Paragon, a source know for quality parts, even back when richard owned paragon. mike

Mike------


This surprises me. Most original Corvette exhaust manifolds were cast of gray cast iron. This is about the "lowest grade" and most basic type of cast iron there is. I'm somewhat surprised that the Chinese can't get this right. As a matter of fact, many OEM cast iron castings of all sorts used in current production cars are sourced from China. Sometimes, the machining is done in the USA but the castings are sourced from China. At the present time, GM has only two co-located cast iron foundries in the USA----a gray iron foundry and a nodular iron foundry located in Defiance, OH. They have only one other in North America, located in Toluca, Mexico.

[Gene M.]

Re: Need Source Recomendations for New Exhaust Manifolds

Chinese steel, cast iron and metal in general has been in the past the lowest quality. Sheet metal resistance to bending gauge size for gauge size compared to USA material is terrible. Chinese steel must have a lot of lead in it.........

[Mike F.]

Re: Need Source Recomendations for New Exhaust Manifolds

I'm not sure how bad the OP exhaust manifolds are, but some other options available are,

1. Soaking your exhaust manifolds in Evaporust for a couple of days. then rinse/brush off in fresh water, or
2. Search ebay for better looking original manifolds. These can also be soaked in Evaporust if needed.


I've had good luck with the above.

[Greg Y.]

Re: Need Source Recomendations for New Exhaust Manifolds

Thanks to all for your input... I'm going with Paragon

[William F.]

Re: Need Source Recomendations for New Exhaust Manifolds

Where's "Richard" former owner of Paragon, now? Has he started another Corvette parts business?

[Joe L.]

Re: Need Source Recomendations for New Exhaust Manifolds

Where's "Richard" former owner of Paragon, now? Has he started another Corvette parts business?

William------


Yes, I believe that after his "non-compete" period after the sale of Paragon expired, he got back into the Corvette parts business as kind of a "specialty" supplier. He advertises with full page ads in the Driveline.