BTU+ is not a cetane improver, therefore engines should not become hotter just because you added BTU+ to the diesel fuel.
...those cetane improvers are generally not recommended unless the diesel fuel being used does not comply with OEM cetane requirements. At first such engines must be top shape, clean inside and not producing the OEM designed outputs... these are very rare cases and the "additional" cost of cetane improvement per Liter of diesel is typically quite more than the benefit (you will need to add more Rupees per Cetane value increased).
BTU+ will SMOOTHEN the sound of the engine, you will feel it "lighter", and specifically when combined with monolec EO, will QUIETEN the diesel engine because monolec has high load bearing ability (absorbing shocks) and significantly reduces the millions of "miniaturized seizures" that normally occur on the engine moving parts, by reducing friction by 24.2% as proven in sophisticated radioactive wear tests of actual engines' piston skirts.
BTU+ is a truly multi-functional, high-performance, low-dosage solution that brings out the optimum efficiency from the engine and enables maximum combustion-ability of the diesel fuel, by utilising the otherwise wasted "potential energy" that is already stored in the diesel you are using ! (It helps to "harness" or RECOVER this hitherto "lost" fuel energy... which is wasted typically due to friction, heat and wear caused by the deposits in the engine and the unstable nature of diesel fuels.)
So every engine no matter what the state of health and mileage, should benefit. And the drive becomes "more pleasure" as the engine is breathing better due to "less frictional heat" and converting most of the energy into Thrust to move the engine, instead of Smoke and Pushing unburned diesel!
By stabilizing the diesel Btu+ helps in a more uniform (smoother) fuel burning in the combustion chamber.
Simultaneously, BTU+ also first Cleans the Injectors/Nozzles, Piston Heads, Rings and Valves, etc., and then "coats" these critical fuel system parts, thereby reducing Friction and heat losses and reversing the "deposit-formation" from the impurities and dirt entering with the diesel fuel. For this, BTU+ is EPA approved.
BTU+ is a technologically advanced solution to keeping your engines in top shape and helping to prolong the engine life, through "safely" cleaning it, preventing carbon and sludge deposits, eliminating free water, and with an adequate lubrification; all these specifically in the upper cylinder area.
Therefore btu+ helps normalize the exhaust temperatures to the nearest to the ideal range as per the OEM designed values. We have no such data on EGTs (sorry, customers' confidential data cannot be posted!) but if you have diesel engines then you can create your authentic EGT numbers and share with us all !
Hope this helps. :)