77 coolant temp sending unit

**warbird51** · 04-22-12, 04:40 PM

I have a 77 Vette with a 92, 350 engine in it. My coolant temps only get up to 120 - 130 degrees on the guage. I bought a correct sending unit for the car and the pipe thead is larger than what is in the engine head. I'm not wild on trying to drill out the head for the larger thread while it's on the engine. Corvette Central had a unit that was adjustable to dial in the temp reading. But, it only works if the temp reading is too high. Ae there any options other than drilling the head to accept the stock 77 sending unit? The thermostat is working correctly.

Wayne

**Crimson Thunder** · 04-23-12, 09:55 AM

Go to the plumbing section in Home Depot and find the correct adapter. It won't look pretty but will work correctly. I have a pic of mine somewhere, i'll see if I can find it.

**Crimson Thunder** · 04-23-12, 10:10 AM

Here it is.

**Peer81** · 04-23-12, 10:23 AM

Two things that come to mind. Behind the gauge is a ceramic resistor, you can change the resistor to get the reading higher or lower.
Second isn't the 92 (LT1?) engine not a reverse flow so the coolant temp can be lower at that point as a GEN1 engine?

Greetings Peter