I've been doing some research regarding the legalities of building a hood stack for my '92 D350. Seems Idaho law says its ok, so long as the exhaust gases exit above the cab. An ISP who pulled me over for going too fast(me...going too fast? Who da thunk it ROFL) said he did not know of any law prohibiting a hood stack in Idaho. His concern was mainly visual obstruction. So, with those thoughts in mind, I'm working on a hood stack for my rig. I'll post pics as I make progress.

I'm using 4" exhaust pipe bought from NAPA. This is a pic of the segments I cut off of the pipe.

Here is a pic of the 90 degree hood stack elbow tacked together.

I had to add a thinner segment to the elbow to get it close to 90 degrees. I'm about 1-1.5 degrees off from 90. My 9" side grinder will take care of this issue XD

This is what the elbow looks like after smoothing out the welds.

Pic with the elbow painted.

Started machining the flange for the elbow. I use an old 1936 Reed-Prentiss lathe for this machining. If you have the patience, she still works just fine, just ask Mopar1973man. The mounting flange needs to be 4.4-4.75" OD, 4" ID, .290" thick, and tapered to .150". Taper can be no longer than .120" with my setup.

A bit more machining done here...should have the flange finished and welded to the elbow by tomorrow night

Elbow flange has been cut out.

Flange is tacked to the elbow in this pic. I ran out of carbon dioxide for my MIG welder....otherwise I would have welded the flange all the way around. BTW, I'm at a perfect 90 degrees now . Tomorrow I'll run to McCall and pick up another 5 lbs of dry ice so I can finish all my welding on the stack.

For those of you that use a MIG welder with carbon dioxide, you can substitute dry ice instead of taking your bottle to Norco or Airgas. I do the dry ice method because the closest Airgas or Norco shop is 140 miles away. 10 lbs of dry ice will give you 700-800 lbs bottle pressure, and costs $15.

I just finished welding up the flange to the elbow, and I had to add a piece of pipe to the leftover pipe I purchased from NAPA. If it weren't for the rust on the additional pipe, you would not be able to tell I welded another piece to the leftover pipe.

The elbow and pipe have been welded together, welds cleaned up, and painted in this pic.

Very good job! It's amazing how much steel was used just to make a v-band flange!

Well, here it is installed . I'll need to make a flapper for it to keep out the rain and snow.

Got a video of it running? I wanna hear this thing!

No video yet.....I need to commandeer Mopar1973man and his video camera . Rest assured we will be taking some good video.

No video yet.....I need to commandeer Mopar1973man and his video camera . Rest assured we will be taking some good video.

Yeah I was just there today and seen it... Looks good! Sounds awesome... The cab sound isn't bad just at a idle or a light rev. More to come I'll be bringing my video camera with me down to the dyno event... http://forum.mopar1973man.com/threads/5180-IDAHO-Spring-DYNO-DAY-29-MM-Saturday-March-17th-2012 Source... http://idahoturbodiesels.com/vb/showthread.php?t=9003