[TeachMeToMPG]

Bigger is bad for turbo car? I understand 5-inch pipe is excessive, but I would have never guessed it would hurt. Further, I thought the exact opposite for narrowing the pipe. I always thought youd want the pipe the same volume from front to rear. I say volume not diameter because the shape may change giving different diameters but the same volume.

I'm gonna try to get out to the car today and yank off the muffler. So far I'm running the stock size pipe.

My miliage bounces from 56-61mpg per fill-up. It all depends on PENDOT's construction, my flight schedule, and if folks car drive and not play bumper cars on I81.