Help me build an exhaust

Your ears will thank you years from now, if you keep them behind the cab.

 

ESPECIALLY if you are going the straight pipe route, and you will still hear it plenty well enough too.

 

Is your exhaust above or below your frame currently?

 

What I would do....

Get a generic Y pipe and figure out how to get it under your sleeper close to the rear of the bunk. Figure out what pieces and elbows you need (or even just flex pipe since it won’t be seen) and get the exhaust to the rear of the bunk at the outside corners. Get whatever size straightpipes you’re going to run with a 90 degree elbow at the bottom. Then I’d just mount the pipes directly to your headache rack, between the headache rack and the back of your bunk.

 

Where the cab supports crosses the frame a 5 in pipe will not fit, you will have to get creative and notch a flat spot in it, both sides.

 

The flat spot must be a later thing,or specific to the 9400. My 9300 Eagle was a 95,N-14 500. Exhaust ran from the turbo,straight under the cab to the y pipe,under the sleeper. 5" all the way to the tips,nothing necked down,or crimped. Owned that truck 20 years,replaced every part of the exhaust a few times,just as simple as could be,fixing it. I don't know what part of the world you're in,but I still have the pair of factory frame mounted muffler brackets,squirreled away in a barn somewhere,if your interested. Heavier duty than what you have pictured,no bracing rod needed like on yours. Would easily hold straight pipes,as it used to hold my muffler and pipe assemblies. I don't have a pic of them from the rear,just this old pic from when the truck was still pretty new,before I replaced them.