I have 535 with the custom Superchip, will after I installed RD header, found out that the car is knocking in the 3, 4 gear but not all the time. My friends told because of the chip, and the chip was not made with the header, have tried octane booster but it didn't work. I am using 90 octane and there 95 octane, will it help if I put few gallnos to raise the octane, and stop knocking.