i left that rusty Doorstop converter in part 1 with it's life long owner, he wanted too much & was too hard to deal with.
i found another, stashed in a bedroom drawer from a poor sap who gave up on life when his missus of 12 years walked out on him 15 years ago. this is definately well looked after but the owner has no idea where he got it from. it stalls @ 5200 behind a 860 HP B1 tunnelramed A body so i'm guessing it'll stall about 4800 behind a 600 odd HP motor in a factory stock heavy E body 'cuda.

it has a few #'s stamped on it but i think this # is the part #.

359 D-8 C2X. AND SP5215 looks like it might be the serial??

it's a 8" something but the clue might be the round flexplate mounts. almost everything i've seen has a square block.

so anybody hazzard a guess?

I didn't post on your first vert because we have one that looked like the very same as you found, we run it in a street/sportsman car it goes @ 4000 stall, works great!
Now this new one you show pics of looks to be a nice made vert, , ,no not the paint lol
Hard to say whom the manufacture is, maybe a first gen A1, poss coan??

Much better looking. Converters are in my opinion can make or break a car. So with that said I would never buy a old used converter. The number on the unit will tell you who built it the first time. The problem is how many times has it been readjusted or blown up and who messed with it to do that work. A buddy of mine bought 2 used converters and after they did not do what they were supose to do he had them cut open. One was total junk inside and the other was old and had to have alot of new parts in it. He has well over a grand in these. He could of bought a brand new on made for his car for alot less.

unfortunately i'm screwed when i comes to buying brand new. i live on the opposite side of the globe & to get a converter sent down under plus the currency exchange, a $1000 convert becomes $2000 of our dollars by the time i get my hands on it. but the racer who owns this hasn't been out much in the past decade so i can say it hasn't had a lot of use. so just need to find the brand & i'll make my call from there.

I have an 8" A-1 that looks identical to this...except the blue paint.
Mine even has the D-8 C2X in the number.

Boss hog jk

Bought it new from A-1 around 1990,
I have it in my street car...'74 Duster. factory 360 car.
Great piece....drives like a normal convertor.
Stalls at 4000 w/ stock stroke motor.
Car went from 12.80 to 11.90 with just the converter change, old convertor was a B&M Holeshot.