The word "All" wasn't the perfect word, but the vast majority do use dynojets. And any dyno that "corrects" to a DJ is just adding in the DJ inflation factor.
I have yet to see any manufacturer claim their gains in real % other than the outrageous marketing claims like "up to 20% more power", et al. When a parts manufacturer uses a DJ dyno for a baseline and max power, then that difference is also inflated by near 20%, it's simple math.
We are not at all bad mouthing any of these manufacturers, as we have run independent back to back tests on a number of systems on the same dyno on the same day (Volant was included in that test). ALL performed quite a better than the stock box and tube. None lived up to any manufacturers claims, but that is to be expected.
