Just installed a new 4-2-1 (1423 setup) header on my auto swift. power comes at a very low 1789rpm (based on RSM) and cannot feel the VTC kick in at 4000rpm anymore, cuz it revs all the way to 6500rpm freely. unfortunately, there is this weird sound between 3000rpm to 4000rpm.....sounds super cheap, can hear the muffler rattles. As the motor revs to 6500rpm, and changes gear, there is a burst of air at the muffler there too. I oni changed the header, nothing else. wonder what is wrong.....
Ask a question, start a discussion or post something for sale!