OK, so I fixed my heat riser flapper leaking issue. Indeed, when I give her the gas, up hill, high load, on Monday on the way to work, I didn't hear the loud awful sound. So, it was apparently an exhaust leak and my worries were over....or were they...

By the end of the week, I was hearing something under load again. So maybe I didn't get the exhaust manifold or downpipe snug enough. I'll check next weekend.

I did have a heat soak issue. I was in 100 degree heat, sitting in traffic for about 30 minutes. The heat under the hood eventually built up where my carbs flooded due to the gas percolating in the float bowls. I pulled over and when I touched the carbs they were hot to the touch. My heat shield was also hot. So....

This weekend I added ceramic heat shield, boom mat self adhesive, to the bottom of the heat shield. See:

http://s785.photobucket.com/user/67dart ... sort=3&o=4

http://s785.photobucket.com/user/67dart ... sort=3&o=3

This stuff is 1/8" thick ceramic fiber with embossed aluminum and can withstand/repel 1750 degrees F. I had to remove one of the linkage bosses from the Offy near the front carb due to the thickness of the boom mat.
http://s785.photobucket.com/user/67dart ... sort=3&o=2

This extra shielding should provide more heat reflection. Here is the installed upgraded heat shield:

http://s785.photobucket.com/user/67dart ... sort=3&o=1

http://s785.photobucket.com/user/67dart ... sort=3&o=0

Of course, in that much heat, standing still for such a long period. It could well be that under hood temps get too high for carbs even with the heat shield.

FYI,

Brian

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