Tech laid out the good for you.

In my opinion, they are great engines. I had two trucks with them, T400s, and 4x4, 3/4 ton work trucks. they ran like draft horses. I never had overheating problems, but they were both stock 400 foundations with torque maker cams, headers, and blueprinted Quadrajet carbs, and HEI ignition. I towed heavy trailers and hauled heavy loads for long miles, and they seldom gave me any trouble; scheduled maintenance and attention to general care was of the utmost importance, though. If I was looking, and could get my hands on a stock 400 long block, I would feel like I found a diamond in the rough.

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