3942527 & 3946826 Reproduction 70 Z Exh Manifolds
 

Is anybody familiar with the reproduction 527/826 Exhaust Manifolds that were made
back in the 1990's ((????)

How can you tell them from OEM Originals ??????

Hi Chuck,
I think you are referring to the one's sold by D&R?
https://www.ebay.com/itm/272928983922
I understood that there were two versions made, that the earlier version (not sure when) had some casting details that were readily apparent and that they were updated and are now harder to tell the difference. One detail for sure is the date code is static at E288 (May 28th, 1968) but this faces the engine block and is hard to see, even on a lift. I'm sure the casting finish is a bit different than the OEM's but of this is an issue just buy the uncoated ones and leave them outside to rust for awhile. Make sure they have deep pits and then blast or tumble them and they will look just like used originals. I bought a set for my restoration and was generally pleased. One thing that required some time was the internals had much casting flash. My machinist calls it "rooster combs" so I took a couple hours with die grinder to clean this up. Probably added nothing for horsepower but it made me feel better. I then coated them with Cerakote 50-50 mix of glacier black-glacier silver. I would characterize this color as "just blasted-tumbled" as it is on the bright side of gray rather then the usual "seasoned skillet" darker gray cast iron look.

Found this on Camaros.org:http://www.camaros.org/forum/index.php?topic=2239.0

Dave,

The new, never mounted reproduction manifolds I have were not purchased from D&R

They are dated F-7-0 and F-10-0

The 1990’s manifolds were reproduced by Durability Plus.

"The best paint for any exhaust manfolds is the VHT #SP998. That is what we use for our reskinning process.

Jerry"