there is a web site devoted just to 1969 440 6bbl/six pack b bodies , the have a lot of info from when these cars were built, they were all built at the Lynch Road plant, and there is a very COPOish type print out of special instructions on how to build and code the vin on these cars along with where the special engines will come from etc. All the cars were built in 1 run so you could not go to a dealer and pick your options and then wait for the car, none had AC for example, all had DANA rears with 4.10, the automatic cars had 383 type converters but internally the trans had HEMI bands and and extra clutches. The 4speed
cars had HEMI trans with 18 spline input shafts. The production of these cars ended when Chrysler ran out of aluminum intakes to put on the cars. Edelbrock could not supply enough. That is why the 70 cars had iron intakes Chrysler cast them at one of the foundry's they had the other iron manifolds made.
I can tell you from personal experience these cars would clean almost any stock street Hemi's clock, I had to spot Hemi cars since AHRA ran cubes to weight and my 6pack bee ran C/Stock Formula 1 and a 426 street Hemi ran E/Stock Formula 1 . My handicap was a 7 and the Hemi was a 9 . I only ran 1 COPO car ever and it was a Chevelle we ran 4 times I won 3 , I do not think I could have beaten a ZL1 because back then we both would have had slicks and that lightweight would do the job.
the web site is
www.homestead.com/sixpacksixbbl/index.html
Larry