D^2 You wrote. > I think the explanation may be in the carburetors, but it gets confusing there too. Both have spread bores. The LeBaron has an unusual Rochester (with fairly small primaries) and the sedan has a "standard" (a bit bigger primaries) Carter. It is likely that the accelerator pump on the LeBaron is not properly set, and causes the lag. Also, there is a spacer to get the Rochester to fit, and may be the spacer kills the low end. Also, the two cars have different torque converters. The LeBaron has a lock up converter from the late seventies, which seems to be slipping a bit more. So, the LeBaron should have had the edge during the initial take off, but it doesn't! > D^2; Do yourself a favour, 86 the Rochester carburetor on the LeBaron and pick up a Carter A.F.B, they are much more reliable and better designed. The Rochester is likely a Quadrajet, or something similar, pulled off of a Chebby and shoehorned to fit on your 440, it is certainly not a stock item. Rochesters were a cheap in house made carburetor that G.M wouldn't even use on most of their higher end cars. In fact they are so lacklustre in performance that most of the Chebby boys swap them for a Holley in their Camaros, and the like, the first chance they get. By the way, the bore to stroke measurements on an old straight eight Chrysler, at least in the 40's, was 3 1/4'' by 4 7/8'' inches. Best Regards Arran Foster 1954 Imperial Newport Needing A Left Side Taillight Bezel And other trim parts.