[msinghof]

Thanks for the responses! Tim, I agree with your logic that there will be heat transfer to another metallic material adjacent to the pipe, but will it also reflect some back? The blisters are already there and more have not appeared with the shake-down road check so the thought was to cover what is there and hope more do not appear further out around a trim ring.

As for the engine running lean that could be. I have not checked idle circuits yet with a vacuum gauge. Southern Automotive built this motor and they were to go through carb, valve lash, and timing twice during a two hour hot run.