I'm installing a engine block heater into a Toyota Prius. I need to get some silicon heat transfer grease, but everything I find is geared towards electronics. Does anyone know what I could use for an engine block heater installation?

Thanks

http://www.permatex.com/products/automotive/thread_compounds/a_thread_sealants/auto_Permatex_Thread_Sealant_with_PTFE.htm

Silicone based anything is very bad for oxygen sensor. They should not be used.
Note the above link suggests temperature sensors as an application.

I don't need thread compound. The EBH doesn't screw in. It snaps in place. It came with a tube of silicon heat transfer grease which you coat the EBH with before you slide it in its location on the block. It's for helping heat transfer from the heater to the block.

I'm installing a engine block heater into a Toyota Prius. I need to get some silicon heat transfer grease, but everything I find is geared towards electronics. Does anyone know what I could use for an engine block heater installation?

Thanks
You are referring to the engine block heater that operates in the cooling system to keep the coolant warm to prevent freezing?
How is it being installed? Does it press into a freeze plug opening? If that is the case, liquid teflon should suffice. Did you check with the block heater manufacturer?
The heat transfer is more to the coolant than to the engine block.

Thanks. It does go into the engine block, but it has a machined hole to go into. It doesn't replace a freeze plug. And it doesn't go into the coolant.

http://www.grainger.com

Search heat transfer paste.

Just FYI to anyone reading this thread, The Toyota Prius has a coolant storage tank which keeps coolant stored over 100* up to 36hrs.
First gen Prius does not.