My future project is to turbocharge my 911SC. With that in mind I've been meaning to hookup a thermocouple to monitor my EGT temperature. My 911SC had smog gear at some point in its life which was disconnected and the hoses were blocked off.
First I removed the smog pipe from the head. It came off very easily. You can see the hole going into the exhaust port below:
Here is the smog pipe that fits into the exhaust port.
I had a 1/8" diameter K-type thermocouple in stainless steel sheath. I drilled a 1/8" inch hole on the tip of the smog pipe so that the thermocouple sticks out a bit. Here it is with the thermocouple sticking out about 1/8".
The thermocouple was brazed to the end of the fitting so that it would not slide up and down. I carefully measured the maximum allowable distance the thermocouple could protrode without hitting the exhaust valve. 1/8" seems to be safe.
The assembly was reinstalled back into the smog fitting on the head.
I hooked it up to my digital display and started her up. After a few minutes EGT reached 600C (1112F). I'll take her for a ride tomorrow and see how high the EGT hits. I need to route the wire properly into the cabin and find a nice spot for the display.
Anyone have any insight as too what a dangerously high EGT temp is for the 911 engine?
Cheers,