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Older posting on this topic is now locked...curious if anyone
has manged to replace the flex pipe without removing the headers
or heat-exchanger. In my case the flex pipe is not welded to the
flange slip-on at both ends (thanks Jim L. for the size and where to
get this stuff). It does not look like this flex pipe will compress enough
to flip the flange aside and replace the flex pipe. But I haven't done
this before to know for certain. If so, off with the converter as the
headers are potentially a place for other things to go bad.

I left the headers in and unbolted the heat exchanger.

Thanks! My route too in that case !

The one time I removed the headers out of the 3 times I've done this upgrade, two of the exhaust studs snapped resulting in some unpleasant words. It's much easier to grind the welded on rings from the headers with the headers off but doable without. If you remove the battery box splash shield, the batteries and the battery box, access is much better.

I felt that both of my trucks had sufficient header pipe extending past the welded rings that I did not remove the rings; clamped the flex pipe to the ~3/4" of pipe and bolted the flange right to the heat exchanger. Maybe I got lucky? But I haven't had any problems since they were installed many years ago.

Fortunately for me, this flex conversion was done long ago.
The flex pipe in Mozo has to be 10+ years old now and just
this weekend one decided to develop a crack along a seam.
Not bad longevity given these were for temp usage. I'll be
taking the converter off and leaving the headers in place. I
have a Pyrometer on each port so it's just begging for something
to break. Darn! Just checked my gasket spares box and
I need one more gasket -- off to the EI WEB page

Fixed, but now I know why it broke and you may want to watch out too!

My flex pipe split due to the Heat Exchanger hanger bolts stripping out
resulting in the weight of the exchanger and muffler stressing the flex pipe.
It was hard to see this as the bolts on top of the exchanger were in place
and the amount of sag was not significant enough to notice.

The threaded holes in the exchanger are Aluminum, must have been
over torqued and eventually completely stripped out. Easy to fix with
Helicoil, see PIX's.

Now on to the Shocks.

ron

Just received my new flex pipe kit from SAV. Will attempt to install tomorrow as it is supposed to be a lovely day here in Denver, perfect for working on old vehicles. I'll use the pinz as a shade tree and hopefully stay cool under there. Probably not going to replace the gaskets at the manifold, just the flex.

krick3tt wrote:Just received my new flex pipe kit from SAV. Will attempt to install tomorrow as it is supposed to be a lovely day here in Denver, perfect for working on old vehicles. I'll use the pinz as a shade tree and hopefully stay cool under there. Probably not going to replace the gaskets at the manifold, just the flex.

You probably woulda had better luck if there wasn't a newbie hanging around, asking a bunch of questions. Nice chatting with you.

Was not a problem. Enjoyed the visit. We'll have to plan a trip soon.

I'm out of parts now, while under there loosening bolts and dropping the heat exchanger and exhaust to remove the old flex I noticed that several of my heater hoses were disintegrating and should be replaced. Unfortunately the local auto parts places do not sell the correct size and even the VW dealer does not have anything that will work. Called SAV and left a message, hope they call me on Monday so I can get them ordered...always something.

I think that Spruce Aircraft had a better insulated, silicone coated hoses that fit. Do a search, these have been discussed before and IIRC seemed to be preferred, even to stock.

Thanks for the tip. Ordered hose from them. At least they have the correct size.

OK...next subject. Anyone know how far the tail pipe goes into the exhaust? The tail pipe is welded in at an angle and I was thinking to have a shop weld in a plate with an elbow to turn the tail piece toward the rear to reroute it higher and farther back. The exhaust cylinder is in very good shape and it seems a shame to buy a new one that exits out the rear.

Or...would it be easier/better to just have a piece bent and cut the existing pipe off and have the new one welded on to the stub?

All this comes about as I am waiting for new heater hose to be delivered and while the exhaust is off, having this possible work done.

Any thoughts?

Check out Pinzinators post here: viewtopic.php?f=13&t=8684&p=63986&hilit=exhaust#p63986

I think it is a great solution vs buy a new rear exit muffler

Here is a shot from the EI website of their aftermarket repo:

Just finished the flex exhaust a couple weeks ago. Aircraft spruce sceet flexhoses for heater are great. One tip, if the exact size is not available, go slightly bigger rather than smaller, the wire cable compresses easily with a hose clamp to fit if slightly large but doesn't expand easily to fit if slightly small (I thought it would, but it doesn't).
I took exhaust manifold off to grind the ring welds. This was a bit time consuming, but can't imagine doing it cleanly with pipes installed.
The exhaust studs were an issue but I didn't break them - medium heat to surrounding metal, hammered (gently) on the studs axially, and "double nut" on the studs to give something to torque onto. They all came out eventually, replaced them as well as nuts and gaskets from SAV (good idea to order these in advance).
The heat exchanger does have some forward-back adjustment of roughly 1inch, to help things fit into place. Also, when in place the SAV flex piece can be tapped on gently to increase length, to give good overlap onto the pipe where it is clamped.
The combo with the EI SS exhaust is way better than where I started. No more exhaust smell in cab, quieter, no more decel backfires, etc.