Last year after the fall bug run, you may remember, I
purchased and installed a new EMPI GT exhaust for the bus.
I really like that exhaust, the look, the
sound, etc.
It is just a nice exhaust,
however, it doesn’t work very well for a bus!
The problem lies with aerodynamics.
Apparently, there is a large swirl that forms in the back of the bus.
This swirl seems to keep the exhaust gasses and any other
junk that gets caught up behind there, in a state of swirling suspension until
it finds a nice new resting place, either on the bumper, rear glass, or the
paint on the entire rear of the bus. It
is very messy.
The solution? Exit
the exhaust way off to the side of the bus, just like the VW engineers figured
out many years ago. I guess that is what
happens when you install a beetle exhaust on a bus. Good thinking on my part! (sarcasm)
Well, at a recent VW show I purchased a couple pieces of
exhaust pipe so I could re-work the GT exhaust to be a side exit.
I crawled under and started making a few
measurements.
It looked pretty feasible
so I started cutting!
I started by simply cutting off the passenger side twin
chrome tip. I measured and cut a piece
of elbow pipe to turn the exhaust parallel to the muffler and headed toward the
driver side of the bus. After making
sure things were going to line up, I cut off the remaining chrome tip and ran
the right hand pipe past the left hand exit from the muffler. Next I used another portion of curved pipe to “blend” the
remaining pipes into one nice exit pipe.
After the main plumbing was completed, I used a portion of
curved pipe to blend the exhaust into one of the chrome tips I had previously
removed.
I tacked it all together to make sure it was straight and
square. I then welded all the seams
solid, cleaned the pipes with solvent and scuffed them up a bit with fine
Scotchbrite in prep for paint.
I painted my new pipes with a high temp header paint and
re-assembled the little bits I had to remove to complete the welding and
painting (bumper and rear apron.)
I like the sound, it sounds the same as before, just a bit
quieter. I will have to report back on
the performance and how clean the back of the bus stays. I don’t have any “longish” trips planned to
test this out any more this summer.
One additional modification I think I may do is to remove
the double chrome tip and replace it with
curved piece so it looks very much like the stock exhaust, only with a
much nicer tone. I think It’s down to the appearance
now.
