On page 26 of the February (!), 2007 Hemmings Classic Car magazine is a picture of the batwing or delta air cleaner as installed on a 1956 Cadillac Eldorado. 305 HP is claimed from 365 cubes. I understand the batwing was manufactured by Delco for Cads, Chryslers and some other car (perhaps a T-Bird?). Note the fancier fasteners holding the oil bath pots. Additionally, the Cad batwing appears to have a Cadillac "Vee" on top and does not appear to be interchangeable with those on the 1955-56 Chrysler 300's. According to Hemmings, the Eldorado could be had for 54% more cash than a Chrysler 300B. I drove a '56 Eldorado once and it performed very poorly due to the Rochester carb secondaries getting clogged up from lack of use by the little old lady that owned it. I was happy to blow the cobwebs out of it for her from time to time. I was not in contact with the owner of the only 1955 C-300 in Des Moines, but would have been happy to provide this service to him. I visited that same Chrysler 300 this summer in Iowa, where it has sat outside too long and developed serious rot in floors and door posts. I love that old car, but decided it was too much to bite off to restore it and find an engine for it. C-300'ly, Rich Barber 1955 C-300 (Blows the doors off of '55 Caddys)