Well hello everyone. I just purchased an 89 Comanche for my next project. It has the I6 with the auto tranny. My father is a member on this site and he also has an 89 Comanche that we restored together. My question is... will the motor loose most of its power due to running an open header? I drove it into work today so I could replace the brake lines on the lift and it had no power. Right now the pipe is broken clean off at the cat and I'm hoping that is why there was no power.