There were some "warranty issues" with the Holleys used on the 383 in 1970 and 1971. The fix was to swap the Holley with a Carter AVS. I have heard a lot about the recall, and the TSB's generated by the Holley, but have never found any solid information on either topic. My Holley, on my 1970 383, had old age issues. The metering block was clogged internally with some kind of trash, and I could never get it out. At the time, I could get a replacement metering block from Holley, but it cost as much as their 0-1850, 600CFM carb. I pulled the old one and tossed it in a box, and put the other Holley on. It seems that working examples of the original carbs from those years are getting scarce. If I see one for sale cheap, I buy it to have it near, just in case. Right now, I have a list #6160-1, which I was told came from a 440. I have not done any research to confirm or discover its original application. To me, it's just a Chrysler-specific Holley, and that's enough for me. If you need any parts for yours, I may have something for you.