Originally Posted by cross><hair
So right now you are running the Manis without a corrected tune to account for the extra air? Rob made it sound like it's required to get a custom tune as soon as you install them due to the fact it makes it go lean right away.
You will have to check your individual results. With my testing the mani's and ypipe increased air flow resulting in increased fuel. My 93 tune actually was very conservative afr wise(11's), we were able to push my 100 tune a little more agressive(12's occasional 13.1).