As you know, the stock mounting location for the knock sensor on the LT1 is just above the pan rail screwed into a 1/4" npt hole into the water jacket. The block hugger headers I have come down right next to there and I'm afraid that the heat will burn the wire/sensor. Would the sensor still work if I screwed an iron street elbow into the block and mounted the sensor to that? It would still have a solid connection to the block through the pipe fitting.

 

As long as it can transfer the vibrations through it, it should work.

 

Did you check the block drain plug on the drivers side to see if there is more clearance?

 

Problem solved - I found a boss with a blind 3/8 threaded hole on the other side of the block that was only 2" away from the drain hole that mirrored the original location of the sensor. Fortunately it was 2" in the right direction - away from the headers. Drilled it out and tapped it with a 1/4" npt tap and the sensor screwed in perfectly. The original hole on the other side of the block put the sensor behind the headers and physically interferred with the sensor.

Jim