K
Ken Chambers
Guest
I received the High Performance Muffler Kit (8-28-01HP KIT) today along with
the HP Exhaust Pipe (8-28-02HP). The muffler is constructed of heavy gauge
steel and appears well built. Hugh tells me they are European in design and
manufacture. The tail pipe and engine manifold "J" pipe are locally fabricated
- and that's where the problem begins. While there is nothing wrong with the
quality of the pipes, there is in the design of the "J" pipe when used on early
cars.
It turns out the bottom of the "J" pipe just contacts the hull near the prop
mounting. I recently installed Hugh's heavy duty engine mounts along with new
transmission mounts. The engine is sitting quite high, high enough that the
center of the engine drain plug is about 1/4 inch above the center of the bilge
hole.
I spoke with Hugh at great length about this today and he is baffled since he
has sold a number of them and I'm the first to mention a problem. There should
be about 1 inch of clearance between the pipe and the hull. He confirmed that
the pipe I received is properly constructed. (Holding a carpenter's square
across the mounting flange, go out, then 90 degrees down to the lowermost point
of the bend should be 6.5 inches.) After much discussion, we settled down to
the theory that cars with serial numbers 100xxx - believe it or not - have a
slightly different hull stamping than later cars. Hugh offered other evidence,
as well, to support this theory. It may be that cars with the underside fins
are the ones with the different hulls. Some fins were later removed by the
factory but a telltale ridge was left remaining. This is still just a theory
at this point but Hugh will be checking various model year cars at Celina. So
don't be alarmed if you see some guy fondling your Amphi's "J" pipe.
I checked my other cars and they all appear the same. My fleet are truly
sister cars, all most probably having been on the assembly floor at the same
time. All the serial numbers are very close.
There's a comparison list out there somewhere. Could someone check serial
numbers vs. underside fins. Also, has anyone else installed, or tried to
install, this High Performance muffler kit and run into a clearance problem,
especially on the early cars?
The solution to this problem is quite simple. During fabrication, the "J"
pipes just need to be located further up into the mounting flange another inch
or so before welding. That will provide an inch of clearance on the early cars
and about 2 inches on later ones.
Despite the apparent high quality of the muffler itself, it's not a quick
installation process. Then again, when was exhaust system work ever easy on
any car? It would be nice, however, if the required muffler clamps were
included, as well as the additional brackets that must be fabricated to attach
to the engine mounted muffler brackets. (The instructions call for a 36 inch
length of 1/8 x 3/4 bar stock to make your own brackets). A new exhaust
manifold gasket will also be needed (8-28-10) along with the three special
exhaust nuts (1-01-15).
And a tip for removing the old exhaust nuts. While the instructions recommend
removing the exhaust manifold and cutting off the old nuts, it's much easier to
heat the nuts in place with a welding torch. They'll come off easily. Of
course, you'll need to be extremely careful with that torch in the engine
compartment. Keep a fire extinguisher or water hose at close reach. Chase the
threads afterwards on the three studs with a 5/16-24 die. Use plenty of
anti-seize thread compound when installing the new nuts. You'll be very
thankful the next time you to remove them.
Ken Chambers, CA
'64 Amphi (3)
the HP Exhaust Pipe (8-28-02HP). The muffler is constructed of heavy gauge
steel and appears well built. Hugh tells me they are European in design and
manufacture. The tail pipe and engine manifold "J" pipe are locally fabricated
- and that's where the problem begins. While there is nothing wrong with the
quality of the pipes, there is in the design of the "J" pipe when used on early
cars.
It turns out the bottom of the "J" pipe just contacts the hull near the prop
mounting. I recently installed Hugh's heavy duty engine mounts along with new
transmission mounts. The engine is sitting quite high, high enough that the
center of the engine drain plug is about 1/4 inch above the center of the bilge
hole.
I spoke with Hugh at great length about this today and he is baffled since he
has sold a number of them and I'm the first to mention a problem. There should
be about 1 inch of clearance between the pipe and the hull. He confirmed that
the pipe I received is properly constructed. (Holding a carpenter's square
across the mounting flange, go out, then 90 degrees down to the lowermost point
of the bend should be 6.5 inches.) After much discussion, we settled down to
the theory that cars with serial numbers 100xxx - believe it or not - have a
slightly different hull stamping than later cars. Hugh offered other evidence,
as well, to support this theory. It may be that cars with the underside fins
are the ones with the different hulls. Some fins were later removed by the
factory but a telltale ridge was left remaining. This is still just a theory
at this point but Hugh will be checking various model year cars at Celina. So
don't be alarmed if you see some guy fondling your Amphi's "J" pipe.
I checked my other cars and they all appear the same. My fleet are truly
sister cars, all most probably having been on the assembly floor at the same
time. All the serial numbers are very close.
There's a comparison list out there somewhere. Could someone check serial
numbers vs. underside fins. Also, has anyone else installed, or tried to
install, this High Performance muffler kit and run into a clearance problem,
especially on the early cars?
The solution to this problem is quite simple. During fabrication, the "J"
pipes just need to be located further up into the mounting flange another inch
or so before welding. That will provide an inch of clearance on the early cars
and about 2 inches on later ones.
Despite the apparent high quality of the muffler itself, it's not a quick
installation process. Then again, when was exhaust system work ever easy on
any car? It would be nice, however, if the required muffler clamps were
included, as well as the additional brackets that must be fabricated to attach
to the engine mounted muffler brackets. (The instructions call for a 36 inch
length of 1/8 x 3/4 bar stock to make your own brackets). A new exhaust
manifold gasket will also be needed (8-28-10) along with the three special
exhaust nuts (1-01-15).
And a tip for removing the old exhaust nuts. While the instructions recommend
removing the exhaust manifold and cutting off the old nuts, it's much easier to
heat the nuts in place with a welding torch. They'll come off easily. Of
course, you'll need to be extremely careful with that torch in the engine
compartment. Keep a fire extinguisher or water hose at close reach. Chase the
threads afterwards on the three studs with a 5/16-24 die. Use plenty of
anti-seize thread compound when installing the new nuts. You'll be very
thankful the next time you to remove them.
Ken Chambers, CA
'64 Amphi (3)
