I'M THINKING OF BUYING A 72 SJ BUT THE 455 IS LONG GONE AND IT'S GOT A 400 NOW ... WOULD IT BE WORTH IT TO FIND A 455 AND SWAP IT OUT ?
How are you going to use the car?
I would get the 455 and just keep or sell the 400
If you're not planning on reselling it for a profit and the car is in good condition and you want to just have a nice old car then go for it. But if you're looking at it to make a profit, forget it. Even with another 455 it still won't be a numbers matching car. A Pontiac enthusiast will know what to look for (casting numbers, serial number tag, etc.) and the resale value will still, in my opinion, be greatly diminished. HTH. -Jim
Have to agree with Js08016. While it is a cool car it will never be super collectible or valuable. Spend money on making it into a car you can enjoy, and then enjoy it. If that means putting in a 455, then do it. But maybe it means just beefing up the 400 that's already there and having some fun with it. Good luck with your project.
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