Well...in a turbine...power is basically temp...measured in ITT (inter turbine temp) Some manufacturers call it T5 or other things....but its basically the max temps seen out of the combustion chamber. They are extreme. Engine manufacturers put a cap on that temp. But that mostly for reliability and prediction of overhaul intervals. If an engine is operated at and ITT of 870C for 1000 hours it could be due for overhaul. Now keep in mind we are talking about aircraft that fall out of the sky. So naturally they are conservative. In some cases where no engine with the required power is available..they will use the same engine with e different fuel control and just run it 50 degrees C hottter...now it will make 200 more hp. But they will shorten the overhaul interval to 700 hours of operation time.
What does that mean? You can GREATLY exceed that 1300 hp very quickly. 2000 hp would be a snap. And you could exceed it so much it may destroy the engine in a few runs. So you need to come up with a way stay within the parameters you set. On a turbine...its ALLL about temps. Temps is power..controlling temps is longevity, etc etc.
Buy it...Ill help you any day. I guarentee we could get it running. Mate it to a gear box and put a built powerglide behind it...it would fly! Ill even get you free fuel.
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if it's cheap & reliable, it ain't fast, if it's fast & cheap, it ain't reliable, if it's fast & reliable, it ain't cheap