Hello all,

I am the proud owner of a 1966 Coupe DeVille Convertible that I am in the process of restoring. The dilema so far is do I replace the 429 with a 472 I have and will it work. I will be converting to front disc brakes also. I am requesting advice regarding the swap as to make the best decision for quality performance after the restoration is complete. Thanks in advance for all help provided.
:burn: see you on the street!

that should be a nice looking car, i almost bought a 66 fleetwood, but it woulda probably needed body work, and i would have needed to sell my 83, which woulda been tough.

good luck on the resto mod.

thanks. i have some work cut out for me

Greetings!
I have a 67 eldorado and when I pulled the engine & trans out for a rebuild I found a spacer plate between the engine & trans and a spacer hub at the back end of the crankshaft . The reason for it is that the 429 doesn't match the 68-later BOPC bell housing bolt pattern. If this is true for the 66 engine you would have to change the transmission as well as the engine. Ask any hotrodder , any engine will fit in most any engine bay. I didn't believe that until I saw a 455 olds toronado drivetrain in the back of a chevette! Also, if your 472 has hardened valve seats it will last longer on unleaded than a 429 will . Parts are also cheaper for the 472 than the 429 but you can still get 429 parts from EGGE machine . Personally I would fix the 429 because your car is a convert and if it has a non-original engine in it you will lose a lot of value on the collector market. I wouldn't do the disk brake conversion either but that's just my opinion. If you don't care about collector value , rock on! But if you do care, keep it as original as possible. I realize that it is frustrationg to have the car and not be able to cruise around in it . I have had my 61 convertible for 9 years and it has never been on the road yet. It took 2 years to find the lower rear control arms so I could get it off the trailer! This year I finally found a good front clip for it so I could take it for a spin only to find that the water pump was bad . $ 250 later the cooling system is fixed and I can drive it around the yard. Even after all these years I still look at it and imagine that first ride on the road. I still admire its classic lines and little by little the new parts are making it better, getting it closer to that test ride. In my humble opinion, If you get satisfaction from preserving a piece of history , don't modify it, restore it and enjoy it.