What is a Cummins "red top" engine?

they used red paint to cover up the mistake

 

The N14 was a great engine, we use to get them ordered as a 460 to get the best cam for Jake performance than most of them were derated to 430. These trucks, Freightliner cabovers, hauled 144,000 lbs over two mountains a 55 minute pull, at 95% power factor, up one of them, They had a lot of early injector problems, The radiators needed to be changed from a 3 core to a 4, the odd cam failure, they had oil leaks and broke a few head bolts, once they were repaired to .006 liner height, they did the job for a million four, they were then sold to a hay company and last time I saw them they were all over 2.5 million.
The N14, and the S60 is by far the best of the engines of that period