I agree that with the proper amount of money you can make a 413 sing like a 440...AND...440 parts are much easier to come by. As anyone who has owned both a 413 and a 440 can attest, you're much more likely to be able to walk into Napa and get what you need in a day or two if you have a '66 or later big block. When you're doing the work yourself there is a plethora of information available, and there are many more shops that are 440-friendly. Also, for performance-minded Imperial owners, a 440 offers the opportunity for widely available aftermarket upgrades from mild to radical. It is true that you can do many of the same things to a 413, but that information is hard to come by. Mopar big block performance books are light on 413-specific info. I applaud John for making the old engine available to a list member who needs it for a stock restoration. At least somebody will have the correct engine. And I hope to see you, John, at the next statewide meeting so you can show us what you've got. I'll be ready to unveil my 440 -- correct for a '66 :) -- year after next. -- David '91 K-Imperial driver '66 Crown Coupe project code name Flying Penguin It sounds like it is too late, but frankly, there isn't any reason (other than possibly money) why the 413 can't be made to be nearly, if not as powerful as the 440. At least then it would have the correct engine. Paul >I just pulled my 413 out of my 1965 Le Baron. �I am currently building a 440 for it (I know it's not what came with it originally, but I would like a little more power). >I am offering it to my compadres in the club first before I put it on e-bay.