yes i think the tail cone tune the output thrust power but i think the manufactures use these shorter cone as a limiter also . because both cone size work well on the 750 for example but the shorter one can not put out over 20 lb thrust even with the same compressor and turbine wheel as p120 or the p160 . its like the nozzle on a garden hose difference in velocity.
Any power over 23 lb uses the longer cone. am i the only
one noticing this. Any engine over 34 lb i can,t gave my opinion
on because i never disassemble that size before but the others
i did. My territory on this subject is modifying these parts can give
you the same result as the factory designed