844 25000 engine question

Tiz like every engine. they are all designed to put out that full rated horsepower all day long in each particular application.
They can all push out more; but only in a intermittent application, ie 1 hour or less at maximum output, then less for another hour.
Cats 3208 V8 engine was a classic case. In a turbocharged marine application it was capable of 425hp. But only for the 10 minutes or less needed to get the boat up and planing. after that it only needed half the horsepower to keep it there.

Was a wrench for a number of years(decades), displacement and fuel are not the only points of contention for HP, there is cam timing(valve position), compression ratio and other minor changes primarily metalurgical that need be addressed. Do not know about Allis but Cummins and Caterpillar both had engine casting levels for differed HP rates, on Cummins a series of numbers are cast into the block on the right side looking from flywheel end, as the casting was graded one of the four numbers was ground away IE 1,2,3,4. A #1 block was high nickel high pressure tolerant where a #4 was useful as a stationary engine low HP high rpm continuous operation only. Try to put a series four into a heavy truck and leaks would develop first them fatigue failure of liner bores. Cat had their 'second rate' engines as well primarily for mundane simple high rpm low power ops.

A guy would have to do some allis Chalmers research! Since a dozer engine is not stationary I'd assume would be okay on that end but would have to check everything