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toga Rover
12-15-2013, 10:56 PM
I am at the point of replacing my exhaust system on my '73 109 5-door, I wanted to get the opinion of the forum members of what they have changed (if anything), as to the routing of their exhaust systems.

I'd like to take my front door tops off in the summer, and open the rear side glass to help the breeze exit. As we all know, the bread-box shape of these trucks causes a lot of wind turbulence behind the vehicle. What I don't want to happen is to have exhaust fumes getting swirled back and in thru the rear most windows (to the dismay of the dog or any human companions).

#1. EXIT TO THE SIDE BEFORE THE REAR TIRE

#2. EXIT TO THE SIDE AFTER THE REAR TIRE, STRAIGHT OUT
#2a.(no pun intended here) EXIT TO THE SIDE AFTER REAR TIRE, TURNED DOWN EXHAUST TIP

#3. EXIT TO THE REAR, STRAIGHT OUT THE BACK
#3a. EXIT TO THE REAR, TURNED DOWN EXHAUST TIP

I realize these are not the "tightest" road going vehicles when it comes to keeping the outside from seeping in, but anything I can do to increase the pleasure of the drive will help.

Thanks everyone for your input.

toga Rover
Dave A
Saratoga Springs, NY

SafeAirOne
12-16-2013, 07:07 AM
What's wrong with the factory exhaust routing? On my 6-cylinder 109 5-door, it exits at the left rear corner at an angle without any turn-down. Never had any fume issues, so long as the rear door was fully closed.

toga Rover
12-16-2013, 02:42 PM
When I got the truck, the exhaust was such Swiss cheese, that I was fumigating the truck when I drove. I wrote "if anything" ie.change, as I want to see if anyone has found a better solution than stock.

Dave




What's wrong with the factory exhaust routing? On my 6-cylinder 109 5-door, it exits at the left rear corner at an angle without any turn-down. Never had any fume issues, so long as the rear door was fully closed.

kenscs
12-17-2013, 09:18 AM
I just completely replaced my exhaust system on '71 IIa ex-MOD LHD. The ex-MOD in stock form has a long Mid-Pipe that goes all the way over rear axle and then turns toward the right. The old system was had a leak in it, so I completely replaced the whole system from header to muffler and out. I ended up with the civilian header, mid-pipe and muffler that exits after the tire out the back left side, with a slight angle down almost at a 45 degree angle to left corner. I have a soft top, and drive with the back flap open even in the winter now, and now have zero exhaust smell coming in the cab. I like this configuration because it is cheap, easier to source the parts than ex-MOD and exits on the "correct" side of the vehicle. There are lots of posts in this forum on what makes the "correct" exit side, but basic theory says you don't want to spray bicyclists and sidewalk with fumes as you drive by, so LHD = left exit and RHD = Right exit.

Let me know if you want a photo of the exit. Our hosts have all the parts in stock for this one.

SafeAirOne
12-17-2013, 09:42 AM
There are lots of posts in this forum on what makes the "correct" exit side, but basic theory says you don't want to spray bicyclists and sidewalk with fumes as you drive by, so LHD = left exit and RHD = Right exit.


My RHD, (formerly) 2.6-engined, 109 SW has the exhaust exiting on the left-rear corner. Presumably, without having checked, this was the stock location:

http://farm8.staticflickr.com/7329/11420665225_6da12d89be_z.jpg