ISX Cummins

Right where the exhaust turns up to head to the stack you'll want to put a 90 on it and cut a hole through the back of your cab. Add a six inch piece to that and make sure you seal the area between the pipe and the cab hole. You dont want to risk getting any fresh air in. This will make it super loud and not annoy others on the road.

 

I nearly laughed out loud at this. Too bad all the 6 and 8" diameter stack idiots won't follow this same advice.

 

If you want louder remove the muffler.
Or just install a N14.

 

Theres a switch on the tall shifters to turn up the volume on ur jakes, theres also a button that deploys the shark teeth on the front grill for when ya really wanna be cool, just make sure ur shifter goes up to the ceiling , the short versions are not equipped with these features

 

You need to pull that garbage can size muffler out and go strait up from the y pipe.

 

I put 7 inch on my w9 not alot of room for 8 inch and I have a 2006 870 cummins and it rumbles nice.