It is because the ceramic coating helps keep more of the heat in the combustion chamber instead of disbursing itself throughout the heads and block - heat in the combustion chamber makes it more efficient. It's going to produce the same head regardless but keeping more of it in the combustion chamber and then getting it out before it travels through the heads and block is why the ceramic coating makes more power.


And it was EVOSPORT that did the test on all those expensive exhaust systems that never produced more than 7 RWHP I think on BMWs.