A 4-53 is more than acceptable.
A 4-53T is not quite outstanding, but close...
Obviously my first choice, and yours too?

While I like them, I realize that not everyone is, or will be, a Detroit Diesel two cycle fan, so..
For a diesel about 4-53T size the 5.9 Cummins has a lot going for it. Great reputation and reliability, great power, and lots of cheap potential for more power.

Grigg

•1951 GMC 250 in the Project Journals
•1948 Chevrolet 6400 - Detroit Diesel 4-53T - Roadranger 10 speed overdrive - 4 wheel disc brakes
•1952 Chevrolet 3800 pickup
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"First, get a clear notion of what you desire to accomplish, and then in all probability you will succeed in doing it..." -Henry Maudslay-