His point is that if it isn't good enough to be used on one of the best grand prix race teams that it isn't a worthwhile design. There is some merit to that argument but it has some holes also.
For one, anything that is designed for low rpm power boosting will be of no use for bikes that only operate in the top range of rpm. Two, because of patents it could be that a great design is not used by the Honda race team or any other team that does not possess the patent.
The Singh head, being kin to the other designs mentioned here, has a purpose of boosting low rpm power. It had a good impartial test with dyno testing on a car engine (4 stroke) and from about 2100 to 3500 it did boost power but not a significant amount. It also lowered exhaust gas temperature above 4500 rpm so it would be counterproductive on a 2 stroke with an expansion chamber. That is because a higher EGT is desired at high rpm to get an upper extension to the pipes powerband. The head of a car engine leaves almost no room for the grooves, whereas a 2 stroke head has lots of room. But Singh focuses only on car engines for some strange reason. He is trying to make money by leasing his patented design. No manufacturer has made that deal yet, which is why it is not being used. If it was without patent maybe it would be in use. Anyone here willing to try it out and see if it boosts low rpm power?
